Super P-Force Sildenafil and Dapoxetine Tablet- this drug has embodied the dreams of many millions of men. Most men (and their partners too!) want sexual intercourse to last much longer than the average 3-5 minutes, and for the erection to be powerful all this time. Try this product at least once, be sure you will like it!
SUPER P-FORCE is a medicine that helps men cope with problems arising in the intimate sphere. Its main advantage is that it contains Dapoxetine and Sildenafil, which actively influence the normalization of blood circulation in the genital organ.
Indications for use:
- disorders associated with premature ejaculation;
- weakness of potency.
Thanks to the main active ingredients, the product normalizes blood circulation and restores erectile function in a couple of hours. In addition, intimacy lasts much longer due to delayed ejaculation. The half-life of the drug ranges from 5-6 hours, and effectiveness occurs 40-90 minutes after the first dose.
Compound: Each tablet contains 2 main substances: Sildenafil (100 mg) and Dapoxetine (60 mg).
Super P-Force instructions for use: The initial dosage ranges from 25-100 mg per day. The drug should be taken 1-3 hours before intimacy.
Cautions: Super P-Force is not recommended to be combined with antidepressants, cytocytic inhibitors, monoamine oxidase inhibitors, imidazoles and nitrates.
Side effect: During treatment with this drug, no obvious side effects that lead to serious health problems were detected. However, in rare cases, minor changes in condition may be observed: headache, dizziness, diarrhea, nausea. Increased side effects are possible only by increasing the recommended dose, so you should first consult with a specialist.
Contraindications:
- sensitivity to the active components of the drug;
- arrhythmia;
- cardiovascular diseases;
- aortic stenosis;
- heart failure;
- lactose intolerance;
- hypotension;
- hypertension;
- mental and nervous disorders;
- cirrhosis of the liver;
- convulsive syndrome and epilepsy;
- dizziness of unknown origin;
- hypertrophic obstructive cardiomyopathy;
- previous myocardial infarction and stroke;
- The drug is not recommended for women and children, as well as men under 18 years of age.
Less strict contraindications include:
- exacerbation of a gastric or duodenal ulcer;
- thrombocytopenia;
- tendency to bleeding;
- multiple myeloma;
- sickle cell anemia;
- leukemia;
- deformation of the penis.
Package: There are 4 tablets in a blister, each containing 100 mg Sildenafil Citrate Sildenafil Citrate and 60 mg Dapoxetine Dapoxetine. Blister weight is about 4 g. Weight with packaging is 7 g.
Keep in a dry, cool, dark place away from children.
Best before date: 3 years.
Production: RSM Ltd., India.
Leave o Super P-Force
There are many factors that negatively affect male potency and can cause erectile dysfunction even at a young age. Vardenafil is one of the most popular and effective drugs created to return men to the opportunity to enjoy intimacy. What problems does this product solve: reviews from specialists and patients. When and in what dosages should Vardenafil be taken, does it have analogues that are equally effective, and how do they differ?
Vardenafil is an inhibitor used to restore normal erection in men and to treat premature ejaculation. The product helps to increase the duration and quality of sexual contact, and also has a general strengthening effect on the body and has a number of additional positive effects:
- Increases immunity;
- Normalizes hormonal balance;
- Tones muscles;
- Improves the quality of seminal fluid.
Vardenafil has no direct effect on libido and will not work in the absence of sexual stimulation. It improves blood flow to the genitals, increases their sensitivity and relaxes muscles, which contributes to a stable erection and more vivid impressions from sexual contact.
Duration of action of the drug: 8-10 hours. The effect can be felt within 20-30 minutes after taking the tablet.
Vardenafil can be bought at a pharmacy or ordered online. Average price of the drug: 60-120 rubles.
Indications for use
The drug is indicated for insufficient genital response, that is, with a weak erection or its absence. Also used to prevent premature ejaculation. It can be used on an ongoing basis or as needed.
Like other inhibitors, Vardenfil does not completely eliminate impotence, but can be used as an additional treatment. It is effective in treating erectile dysfunction caused by the following reasons:
- Hormonal imbalance and diseases caused by it;
- Excess weight;
- Poor nutrition;
- Pathologies of the genitourinary system;
- Age-related changes;
- Psychological problems: stress, depression.
Contraindications and side effects
List of contraindications for the use of Vardenafil, specified in the instructions for use:
- Individual intolerance;
- The presence of serious cardiovascular pathologies: chronic heart failure, unstable angina;
- Recently suffered serious illnesses: heart attack, stroke;
- Hypotension;
- Taking other inhibitors and certain medications: erythromycin, clarithromycin, rotonavir, intraconazole;
- Blood diseases: leukemia, anemia;
- Kidney failure;
- Liver failure;
- Congenital diseases of the retina;
- Congenital or acquired deformities of the penis;
- Age up to 18 years.
It is highly not recommended to take the drug together with alcohol: ethyl alcohol inhibits and weakens the effect of the drug, and its effect may occur later than planned. In addition, the combination of two potent substances creates a risk of intoxication.
Violation of the instructions for use and exceeding the dose can cause the following side effects:
- Dizziness;
- Headache;
- Tinnitus;
- Convulsions;
- Fainting;
- Muscle pain;
- Pressure surges;
- Nasal congestion;
- Nosebleeds;
- Visual impairment: distorted color perception, increased sensitivity to light;
- Acute pain in the eyes;
- Nausea;
- Diarrhea;
- Gastritis.
If one or more symptoms appear and intensify, you should seek help from a doctor.
How to use
Vardenafil is available in tablet form and is sold without a prescription. The maximum daily dose is 20 mg. At the first dose, it is advisable to limit yourself to half the dose, and for some diseases doctors advise reducing it to 5 mg. The tablet is taken 30 minutes before the intended sexual contact, washed down with plenty of water. Before use, it is advisable to limit the intake of heavy, fatty foods, giving preference to plant foods and fermented milk products.
For maximum effect, the drug is taken in a course of several weeks, after which a break is taken. It can be combined with most dietary supplements and vitamin complexes.
Analogs
If you are allergic to vardenafil, the body is unresponsive, or are looking for cheaper drugs, you can refer to the list of the best analogues of Vardenafil and choose the most suitable remedy for yourself:
- Viagra. The active ingredient is sildenafil. A time-tested drug, on the basis of which all subsequent inhibitors were created.
- Vardenafil generic A drug identical in composition and pharmacological action is cheaper than the original.
- Cialis. Similar in composition. The active ingredient is tadalafil. The effect occurs 30 minutes after administration, like Vardenafil, but lasts much longer.
- Alicaps. Russian analogue. Unlike Vardenafil, it is a dietary supplement, not a drug. Stimulates the release of testosterone, thereby increasing sexual desire.
- Vuka Vuka. Dietary supplement based on 10 African herbs. It does not have an immediate effect, is taken in courses, has virtually no side effects, and is very cheap: the average cost is 20-30 rubles per 1 capsule.
- Impaza. The drug is available in the form of lozenges. Contraindicated only in case of individual intolerance. Intended for long-term use, it gradually normalizes potency and gives energy. Average cost: 20 rubles per 1 tablet.
It is best to select a medication together with your doctor. He will advise the most suitable options based on a specific clinical case.
Sildenafil 50 mg is a potency regulator. The drug is used regardless of gender to increase libido. In clinical practice, the drug is used not only to treat erectile dysfunction, but also pulmonary hypertension due to its vasodilating effect on the vascular endothelium in the pulmonary circulation. The medication is available in an easy-to-take tablet form and is intended for once daily use.
Other names and classification
ATX code: G04BE03.
International nonproprietary name
Sildenafil.
Trade names
- Vertex;
- Dynamic;
- Vizarsin;
- Revatio;
- Sildenafil-C3;
- Tornetis.
Registration number
Composition and dosage forms
The drug is available in tablet form. The core of each tablet consists of the active component - 50 mg of sildenafil citrate.
To facilitate absorption and increase bioavailability, auxiliary ingredients are added to the drug during the production process:
- microcrystalline cellulose;
- croscarmellose sodium;
- dehydrogenated calcium hydrogen phosphate;
- Magnesium stearate.
The mixture of components gives the round tablets a white color. Units of the drug are coated on top with a film coating that is soluble in the intestines. The film is based on talc, titanium dioxide, polyethylene glycol 4000, hypromellose. Tablets are contained in 15 pieces in blister packs. Blisters are placed in a cardboard pack of 6 pieces. In addition, the tablets are available in polyethylene jars of 90 pieces.
Pharmacological group
The drug belongs to potency regulators that suppress the action of phosphodiesterase-5 (PDE-5).
pharmachologic effect
The synthetic drug selectively blocks cyclic guanosine monophosphate (cGMP), located in PDE-5.
Phosphodiesterase is located in the corpus cavernosum of the genital organ in men and in the pulmonary vessels. As a result of achieving a therapeutic effect, erectile function is restored and the natural physiological response to psychological arousal of a sexual nature is improved.
The active component does not have a direct relaxing effect on the cavernous bodies in the genital organ.
Sildenafil enhances the relaxation of the corpora cavernosa of nitric oxide on soft tissue. During sexual stimulation, with increased production of nitric oxide, inhibition of PDE-5 and an increase in the concentration of cGMP are observed. As a result of achieving a therapeutic effect, smooth muscles relax and blood supply to the corpus cavernosum increases.
Sildenafil is a reuptake inhibitor, which helps to enhance ejaculation of the erect penis. In addition, the chemical compound has a vasodilating effect on the pulmonary vessels. Thanks to this effect, hypertension in the pulmonary circulation is reduced.
After oral administration, the tablets are broken down by the enzymatic action of small intestinal esterases, sildenafil is released and diffuses into the local bloodstream.
Bioavailability varies depending on individual characteristics from 25% to 63%. With a single dose, the maximum values of the active substance in the blood plasma are recorded within 0.5-2 hours. The drug substance undergoes transformation in hepatocytes with the formation of an N-desmethyl metabolite.
Together with the metabolic product, sildenafil binds to plasma proteins by 95-96%.
The half-life is 3-5 hours. The drug leaves the body with urine (13%) in the form of metabolites, 80% - together with feces.
Indications for use of Sildenafil 50 mg
The drug is used in clinical practice to treat impotence caused by dysfunction of the muscles of the penis, or to increase libido. The drug is suitable for both men and women and has the same effect regardless of the patient’s gender.
In rare cases, the drug is prescribed for the treatment of pulmonary hypertension as part of complex therapy.
For men
The drug is used to restore potency necessary for satisfactory sexual intercourse and is prescribed for the treatment of erectile dysfunction of various origins.
In the first case, to achieve a stable erection, you need to take the pills an hour before sexual intercourse. It is recommended to take 25-100 mg per day, depending on individual needs and the body’s reaction.
For women
The drug helps to enhance sexual activity and sexual desire in women during menopause or restore libido after surgery for resection (removal) of the uterus. The drug has a positive effect on the female reproductive system, increases the sensitivity of the internal and external genital organs.
The medicine reduces the time to achieve natural arousal and increases the secretion of vaginal lubrication.
The drug can be used in the fight against frigidity.
Method of administration and dosage of Sildenafil 50 mg
To treat high pressure in the pulmonary arteries, the drug is taken 2 times a day with an interval of 6-8 hours between doses. A single dosage is 25 mg. The maximum permissible dosage per day is 60 mg. In case of poor tolerance, the drug is taken once in a daily dose of 25 mg per day.
To treat erectile dysfunction, you need to take 50 mg one hour before expected sexual intercourse.
A single dosage will be sufficient for sexual stimulation in both mild and advanced stages of erectile dysfunction. In some cases, if well tolerated, the dosage may be increased to 100 mg per day. The maximum dose is 0.1 g per day.
How long does it last?
The time to achieve and the duration of the therapeutic effect depend on the individual characteristics of the patient’s body. Mainly from the speed of general metabolism. The average duration of action of the drug is 4 hours, the maximum is 12 hours.
How long can it be used?
For effective treatment of penile dysfunction, andrologists recommend taking the medicine for 2 months. In this case, after a single use, it is necessary to take a break of 24-48 hours before the next dose.
special instructions
Before starting drug therapy, it is necessary to undergo a medical examination to identify pathologies of the cardiovascular system. If you have congenital heart disease or unstable angina, taking the medicine is not recommended.
It is necessary to take precautions and undergo regular examination by the attending physician for patients with anatomical deformation of the genital organ:
- angulation;
- Peyronie's syndrome;
- cavernous fibrosis.
You should take the drug with caution during an erection, which is accompanied by pain due to the development of pathological processes. Priapism can develop due to malignant neoplasms and sickle cell anemia. People prone to bleeding or suffering from ulcerative lesions of the stomach and duodenum must consult a doctor before taking the drug.
In old age
For liver dysfunction
For impaired renal function
Side effects of Sildenafil 50 mg
In the presence of hypersensitivity to the chemical compounds included in the drug, the development of angioedema, skin itching, anaphylactic shock, skin rashes, and the appearance of erythema is possible.
Disturbances in the gastrointestinal tract are accompanied by asthenia, abdominal pain, nausea and vomiting.
When the central nervous system is depressed, the patient may experience a headache, flushing of the face, and loss of orientation in space. In rare cases, insomnia develops.
Disorders of the musculoskeletal system that arise from taking Sildenafil are characterized by pain in the joints and muscles, and an increase in muscle tone of the skeletal muscles.
Breathing disorders are accompanied by nasal congestion, inflammatory processes in the paranasal and paranasal sinuses, and infectious diseases.
In some cases, visual impairment is accompanied by decreased visual acuity and inflammation of the conjunctiva of the eyes. Men are at risk of developing changes in color perception and blurring of objects.
A flu-like syndrome and infectious and inflammatory diseases may occur.
The vasodilating effect of the drug may occur.
There is a risk of developing infections of the genitourinary system and disturbances in the activity of the prostate gland. In exceptional cases, priapism may develop.
Impact on the ability to drive vehicles and other mechanisms
The drug does not cause addiction and does not affect the peripheral and central nervous system. Therefore, during the period of treatment with Sildenafil, it is allowed to control complex mechanisms, drive or other activities in which it is necessary to have developed fine motor skills, reaction speed and be concentrated.
Contraindications
The drug is strictly forbidden to be taken while undergoing treatment with nitric oxide or nitrate donors. Due to the possible development of anaphylactic shock, it is contraindicated to take the drug if you are hypersensitive to the active and auxiliary substances of the drug.
Overdose
- increased body temperature;
- a sharp drop in blood pressure;
- nasal congestion;
- headache and dizziness;
- flushed face;
- blurred vision;
- indigestion.
The severity of symptoms depends on the excess of the maximum permissible dosage. If signs of overdose appear, you must stop taking the drug and drink 10 tablets of activated carbon. If symptoms persist, you should seek medical help.
Interoperability and Compatibility
With simultaneous administration of CYP3A4 isoenzyme blockers, the clearance of sildenafil citrate decreases. With this combination, the serum level of sildenafil in the blood increases.
A similar increase in the concentration of the active substance is observed with simultaneous use of:
- Ritonavir;
- Indinavir;
- Saquinavir;
- Ketoconazole;
- Itraconazole.
Sildenafil can enhance the antihypertensive effect of nitrates.
In post-marketing practice, symptoms of diabetic rhabdomyolysis (acute necrosis of muscle tissue) have been reported after a single use of Sildenafil during drug therapy with Simvastatin.
With alcohol
Sildenafil is a synthetic drug that cannot be combined with alcohol and ethanol-containing drugs. Concurrent use of alcoholic beverages during drug therapy can cause severe dizziness with loss of orientation in space, severe arterial hypotension, respiratory depression and heart rate depression. The body may begin to collapse.
Conditions and shelf life
Manufacturer
CJSC "Northern Star", Russia.
Conditions for dispensing from pharmacies
The medicine is freely available.
Price in cities of Ukraine and Russia
The average cost of a potency regulator is about 163 UAH, while the price range in Russian pharmacies is from 73 to 576 rubles. Generics are more expensive than the original drug.
Analogs
If there is no positive reaction of the body to taking the drug, you can switch to another drug:
- Viagra;
- Dynamic;
- Maxigra;
- Sildenafil "North Star";
- Erexesil;
- Cialis.
A quick word about medications. Sildenafil
Viagra for prostatitis
The combination of a sexual intercourse prolonger and an erection improvement product allows a man to achieve the highest quality sex. Sildenafil with Dapoxetine is one of these combinations. The first substance is part of the well-known Viagra and provides a strong erection. The second is, perhaps, the only really working remedy against premature ejaculation.
How it works
Sildenafil affects blood flow in the cavernous bodies of the penis. This is achieved by blocking the work of one enzyme (phosphodiesterase 5), which leads to increased release of nitric oxide, a powerful compound that relaxes the vascular wall and increases blood flow. This enzyme is found only in the cavernous bodies of the penis, but enzymes similar in structure (phosphodiesterase 1, 2, 3, 4) are present in platelets, myocardium, retina, and skeletal muscles. Sildenafil's insignificant effect on these enzymes causes the possibility of side effects.
Dapoxetine acts at the level of ejaculation centers in the brain. It has the ability to increase the concentration of serotonin, a compound necessary for the transmission of information between nerve cells. This leads to an increase in the frequency and strength of inhibitory impulses from the ejaculation centers of the brain to similar centers of the spinal cord. As a result, ejaculation occurs later and sexual intercourse lasts longer.
Sildenafil and Dapoxetine tablets: indications for use
The combination of these two active ingredients should be used in cases of simultaneous erectile dysfunction and premature ejaculation. This condition can develop if:
- The man is over 45 years old;
- Previous injuries to the pelvic area (bone fractures, bruises, muscle and tendon ruptures, prostate injuries);
- Previous spinal injuries (only if sensitivity in the genital area is preserved);
- Atherosclerosis (deposition of cholesterol on the wall of blood vessels) of the iliac arteries;
- All kinds of psychological complexes, injuries associated with the genitals or intimacy.
Also, the combination of Dapoxetine and Sildenafil is suitable for healthy men who want to achieve high-quality and long-lasting sex.
Contraindications
The combination of Sildenafil with Dapoxetine cannot be used in the following cases:
- Allergy or hypersensitivity to these substances;
- Deformation of the penis;
- Blood pressure is above 140/90 mm. rt. Art. or below 100/70 mm. rt. Art.;
- Cardiac pathology (pain in the heart area, shortness of breath during physical activity, interruptions in rhythmic work, disruption of the structure of the valve apparatus, previous myocardial infarction);
- Taking medications for high blood pressure;
- Taking nitrates (nitroglycerin, isosorbide dinitrate, nitrospray, etc.);
- Taking antidepressants in the last two weeks, or within a week after using these drugs;
- Liver pathology (hepatitis, cirrhosis, liver failure);
- Kidney pathology (glomerulonephritis, renal failure);
- Any mental illness;
- Age under 18 or over 65 years.
Possible side effects
Most often, adverse reactions develop as a result of taking medications despite contraindications, or combining them with alcohol. Less often - due to the individual characteristics of the body. Side effects of combining Sildenafil with Dapoxetine include:
- Changes in blood pressure;
- Interruptions in the work of the heart, palpitations, pain behind the sternum of a burning, pressing nature;
- Anxiety, insomnia;
- Dizziness, headache, nausea;
- Change in normal color perception (blue-green);
- Nasal congestion.
In the case of combining medications with any psychotropic substances or alcohol, paradoxical reactions may develop in the form of lack of erection and premature ejaculation.
Mode of application
All combination drugs containing Sildenafil with Dapoxetine are available in the form of tablets coated with a protective film coating. When taken orally, they should not be divided or chewed - this can lead to the destruction of part of the active substance in the acidic environment of the stomach. The tablet should be taken with a moderate amount of water.
The effect gradually develops after 60–90 minutes and lasts for about 4–5 hours. After its completion, the strength of the erection and the duration of sexual intercourse return to their original values.
Sildenafil + Dapoxetine = Super P-Force
One common combination drug containing these active ingredients is Super P-Force. The medicine is produced by the Indian company Sunrise Remedies, specializing in the production of products to improve the quality of sexual life. It contains 100 mg of sildenafil and 60 mg of dapoxetine. Super P-Force is sold in blisters of 4 tablets, costing from 330 to 720 rubles. You can buy medicine in pharmacy chains or order it online.
The drug has collected many positive reviews from men who have tried it. The development of side effects is most often associated with non-compliance with the rules of taking the drug, or individual intolerance.
Sildenafil + Dapoxetine – where can you buy it?
In addition to Super P-Force, there are several other drugs with a similar composition and dosage: Cenforce-D, Super Kamagra. They differ from each other by manufacturer and slight price fluctuations. Extra Super P-Force contains 100 mg of Sildenafil and 100 mg of Dapoxetine. You can buy any of these drugs in pharmacy chains or order online.
A drug for the treatment of erectile dysfunction. PDE-5 inhibitor
Active substance
Release form, composition and packaging
Excipients: microcrystalline cellulose - 50 mg, lactose monohydrate (milk sugar) - 61.5 mg, croscarmellose sodium (primellose) - 7.5 mg, (medium molecular weight polyvinylpyrrolidone) - 4.5 mg, magnesium stearate - 1.5 mg.
Shell composition: Opadry II (polyvinyl alcohol, partially hydrolyzed - 2 mg, titanium dioxide (E171) - 1.145 mg, macrogol (polyethylene glycol 3350) - 1.01 mg, talc - 0.74 mg, aluminum varnish based on brilliant blue - 0.096 mg, iron oxide (II) yellow (E172) - 0.0085 mg, iron oxide (II) black (E172) - 0.0005 mg).
Film-coated tablets blue, round, biconvex; at the break - white or almost white.
Excipients: microcrystalline cellulose - 54 mg, lactose monohydrate (milk sugar) - 74 mg, croscarmellose sodium (primellose) - 10 mg, povidone (medium molecular weight polyvinylpyrrolidone) - 10 mg, magnesium stearate - 2 mg.
Shell composition: Opadry II (polyvinyl alcohol, partially hydrolyzed - 2.4 mg, titanium dioxide (E171) - 1.374 mg, macrogol (polyethylene glycol 3350) - 1.212 mg, talc - 0.888 mg, aluminum varnish based on brilliant blue - 0.1152 mg, iron oxide (II) yellow (E172) - 0.0102 mg, iron oxide (II) black (E172) - 0.0006 mg).
1 PC. - contour cellular packaging (1) - cardboard packs.
2 pcs. - contour cellular packaging (1) - cardboard packs.
4 things. - contour cellular packaging (1) - cardboard packs.
7 pcs. - contour cellular packaging (1) - cardboard packs.
7 pcs. - contour cell packaging (2) - cardboard packs.
8 pcs. - contour cellular packaging (1) - cardboard packs.
10 pieces. - contour cellular packaging (1) - cardboard packs.
10 pieces. - contour cell packaging (2) - cardboard packs.
20 pcs. - polymer jars (1) - cardboard packs.
20 pcs. - polymer bottles (1) - cardboard packs.
Film-coated tablets blue, round, biconvex; at the break - white or almost white.
Excipients: microcrystalline cellulose - 83.5 mg, lactose monohydrate (milk sugar) - 83.5 mg, croscarmellose sodium (primellose) - 15 mg, povidone (medium molecular weight polyvinylpyrrolidone) - 15 mg, magnesium stearate - 3 mg.
Shell composition: Opadry II (polyvinyl alcohol, partially hydrolyzed - 3.6 mg, titanium dioxide (E171) - 2.061 mg, macrogol (polyethylene glycol 3350) - 1.818 mg, talc - 1.332 mg, aluminum varnish based on brilliant blue - 0.1728 mg, iron oxide (II) yellow (E172) - 0.0153 mg, iron oxide (II) black (E172) - 0.0009 mg).
1 PC. - contour cellular packaging (1) - cardboard packs.
2 pcs. - contour cellular packaging (1) - cardboard packs.
4 things. - contour cellular packaging (1) - cardboard packs.
7 pcs. - contour cellular packaging (1) - cardboard packs.
7 pcs. - contour cell packaging (2) - cardboard packs.
8 pcs. - contour cellular packaging (1) - cardboard packs.
10 pieces. - contour cellular packaging (1) - cardboard packs.
10 pieces. - contour cell packaging (2) - cardboard packs.
20 pcs. - polymer jars (1) - cardboard packs.
20 pcs. - polymer bottles (1) - cardboard packs.
pharmachologic effect
Sildenafil is a powerful selective inhibitor of cycloguanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5).
Mechanism of action
The physiological mechanism of erection is associated with the release of nitric oxide (NO) in the corpus cavernosum during sexual stimulation. This, in turn, leads to an increase in cGMP levels, subsequent relaxation of the smooth muscle tissue of the corpus cavernosum and increased blood flow.
Sildenafil does not have a direct relaxant effect on the isolated human corpus cavernosum, but enhances the effect of nitric oxide (NO) by inhibiting PDE5, which is responsible for the breakdown of cGMP.
Sildenafil is selective for PDE5 in vitro, its activity against PDE5 exceeds that of other known phosphodiesterase isoenzymes: PDE6 - 10 times; PDE1 - more than 80 times; PDE2, PDE4, PDE7-PDE11 - more than 700 times. Sildenafil is 4000 times more selective for PDE5 compared to PDE3, which is of utmost importance since PDE3 is one of the key enzymes in the regulation of myocardial contractility.
A prerequisite for the effectiveness of sildenafil is sexual stimulation.
Clinical data
Cardiac research
The use of sildenafil in doses up to 100 mg did not lead to clinically significant ECG changes in healthy volunteers. The maximum decrease in systolic pressure in the supine position after taking sildenafil at a dose of 100 mg was 8.3 mmHg. Art., and diastolic pressure - 5.3 mm Hg. Art. A more pronounced, but also transient effect on blood pressure was observed in patients taking nitrates.
In a study of the hemodynamic effect of sildenafil at a single dose of 100 mg in 14 patients with severe coronary artery disease (more than 70% of patients had stenosis of at least one coronary artery), resting systolic and diastolic blood pressure decreased by 7% and 6%, accordingly, and pulmonary systolic pressure decreased by 9%. Sildenafil did not affect ejection or impair blood flow in stenotic coronary arteries and also resulted in an increase (approximately 13%) in adenosine-induced coronary flow in both stenotic and intact coronary arteries.
In a double-blind, placebo-controlled study, 144 patients with erectile dysfunction and stable angina taking antianginal drugs (except nitrates) exercised until their angina symptoms improved. The duration of the exercise was significantly longer (19.9 seconds; 0.9-38.9 seconds) in patients taking sildenafil in a single dose of 100 mg compared to patients receiving placebo.
A randomized, double-blind, placebo-controlled study examined the effect of varying the dose of sildenafil (up to 100 mg) in men (n=568) with erectile dysfunction and hypertension taking more than two doses. Sildenafil improved erections in 71% of men compared to 18% in the placebo group. The incidence of adverse effects was comparable to that in other patient groups, as well as in individuals taking more than three antihypertensive drugs.
Visual impairment studies
In some patients, 1 hour after taking sildenafil at a dose of 100 mg, the Farnsworth-Munsell 100 test revealed a mild and transient impairment in the ability to distinguish shades of color (blue/green). 2 hours after taking the drug, these changes were absent. Color vision impairment is thought to be caused by inhibition of PDE6, which is involved in light transmission in the retina. Sildenafil had no effect on visual acuity, contrast perception, electroretinogram, intraocular pressure, or pupil diameter.
In a placebo-controlled crossover study of patients with proven early-onset macular degeneration (n=9), sildenafil in a single dose of 100 mg was well tolerated. There were no clinically significant changes in vision assessed by specific visual tests (visual acuity, Amsler grating, color perception, color transmission simulation, Humphrey perimeter, and photostress).
Efficiency
The effectiveness and safety of sildenafil was assessed in 21 randomized, double-blind, placebo-controlled studies lasting up to 6 months in 3,000 patients aged 19 to 87 years with erectile dysfunction of various etiologies (organic, psychogenic or mixed). The effectiveness of the drug was assessed globally using an erection diary, the International Index of Erectile Function (a validated questionnaire about the state of sexual function) and a partner interview.
The effectiveness of sildenafil, defined as the ability to achieve and maintain an erection sufficient for satisfactory sexual intercourse, has been demonstrated in all studies conducted and was confirmed in long-term studies lasting 1 year. In fixed-dose studies, the proportion of patients reporting that therapy improved their erections was: 62% (25 mg sildenafil dose), 74% (50 mg sildenafil dose), and 82% (100 mg sildenafil dose) compared with 25% in the placebo group. Analysis of the International Index of Erectile Function showed that in addition to improving erection, treatment with sildenafil also increased the quality of orgasm, achieved satisfaction from sexual intercourse and overall satisfaction.
According to the pooled data, among patients who reported improved erections with sildenafil treatment, 59% of patients with diabetes, 43% of patients who had undergone radical prostatectomy, and 83% of patients with spinal cord injury (versus 16%, 15% and 12% in the placebo group, respectively).
Pharmacokinetics
Suction
After oral administration, sildenafil is rapidly absorbed. Absolute bioavailability averages about 40% (from 25% to 63%). In vitro, sildenafil at a concentration of about 1.7 ng/ml (3.5 nM) inhibits human PDE5 activity by 50%. After a single dose of sildenafil in a dose of 100 mg, the average C max of free sildenafil in the blood of men is about 18 ng/ml (38 nM). Cmax when taking sildenafil orally on an empty stomach is achieved on average within 60 minutes (from 30 minutes to 120 minutes). When taken in combination with fatty foods, the rate of absorption decreases: Cmax decreases by an average of 29%, and TCmax increases by 60 minutes, but the degree of absorption does not change significantly (AUC decreases by 11%).
Distribution
Vd of sildenafil at steady state averages 105 liters. The binding of sildenafil and its main circulating N-demethyl metabolite to plasma proteins is about 96% and does not depend on the total concentration of the drug. Less than 0.0002% of the sildenafil dose (average 188 ng) was found in semen 90 minutes after taking the drug.
Metabolism
Sildenafil is metabolized mainly in the liver under the influence of the cytochrome isoenzyme CYP3A4 (major pathway) and the cytochrome isoenzyme CYP2C9 (minor pathway). The main circulating active metabolite, resulting from N-demethylation of sildenafil, undergoes further metabolism. The selectivity of this metabolite for PDE is comparable to that of sildenafil, and its activity against PDE5 in vitro is about 50% of the activity of sildenafil. The concentration of the metabolite in the blood plasma of healthy volunteers was about 40% of the concentration of sildenafil. The N-demethyl metabolite undergoes further metabolism; T 1/2 is about 4 hours.
Removal
The total clearance of sildenafil is 41 l/h, and the final half-life is 3-5 hours. After oral administration, as well as after intravenous administration, sildenafil is excreted in the form of metabolites, mainly by the intestine (about 80% of the oral dose) and, to a lesser extent, by the kidneys (about 13% of the oral dose).
Pharmacokinetics in special groups of patients
In healthy elderly patients (over 65 years of age), the clearance of sildenafil is reduced, and the concentration of free sildenafil in the blood plasma is approximately 40% higher than in young patients (18-45 years of age). Age does not have a clinically significant effect on the incidence of side effects.
With mild (creatinine clearance 50-80 ml/min) and moderate (creatinine clearance 30-49 ml/min) degrees of renal failure, the pharmacokinetics of sildenafil after a single oral dose of 50 mg does not change. In severe renal failure (creatinine clearance ≤30 ml/min), the clearance of sildenafil is reduced, which leads to an approximately twofold increase in AUC (100%) and C max (88%) compared with those with normal renal function in patients of the same age group .
In patients with liver cirrhosis (stages A and B according to the Child-Pugh classification), the clearance of sildenafil is reduced, which leads to an increase in AUC (84%) and Cmax (47%) compared with those with normal liver function in patients of the same age group. The pharmacokinetics of sildenafil in patients with severe liver dysfunction (Child-Pugh stage C) has not been studied.
Indications
- treatment of erectile dysfunction, characterized by the inability to achieve or maintain a penile erection sufficient for satisfactory sexual intercourse.
Sildenafil is only effective during sexual stimulation.
Contraindications
- use in patients receiving continuous or intermittent nitric oxide donors, organic nitrates or nitrites in any form, since sildenafil enhances the hypotensive effect of nitrates;
— according to its registered indication, the drug is not intended for use in children and adolescents under 18 years of age;
— according to its registered indication, the drug Sildenafil-SZ is not intended for use in women;
- lactase deficiency, lactose intolerance, glucose-galactose malabsorption;
- hypersensitivity to sildenafil or to any other component of the drug.
The safety and effectiveness of Sildenafil-SZ when used in combination with other drugs for the treatment of erectile dysfunction have not been studied, therefore the use of such combinations is not recommended.
Carefully:
- anatomical deformation of the penis (angulation, cavernous fibrosis or Peyronie's disease);
- diseases predisposing to the development of priapism (sickle cell anemia, multiple myeloma, leukemia, thrombocythemia);
- diseases accompanied by bleeding;
- exacerbation of peptic ulcer of the stomach and duodenum;
- hereditary retinitis pigmentosa;
- heart failure, unstable angina, myocardial infarction, stroke or life-threatening arrhythmias in the last 6 months, arterial hypertension (BP >170/100 mm Hg) or hypotension (BP<90/50 мм рт.ст.);
- in patients with episodes of anterior non-arteritic ischemic optic neuropathy (history).
Dosage
The drug is taken orally.
The recommended dose for most adult patients is 50 mg approximately 1 hour before sexual activity. Taking into account effectiveness and tolerability, the dose can be increased to 100 mg or reduced to 25 mg. The maximum recommended dose is 100 mg. The maximum recommended frequency of use is 1 time/day.
At renal failure mild to moderate(CC 30-80 ml/min) no dose adjustment is required if severe renal failure (SC<30 мл/мин) the dose of sildenafil should be reduced to 25 mg.
Since the elimination of sildenafil is impaired in patients with liver damage (particularly cirrhosis), the dose of Sildenafil-SZ should be reduced to 25 mg.
Dose adjustment of Sildenafil-SZ in elderly patients not required.
Concomitant use with other drugs
When used together with ritonavir, the maximum single dose of Sildenafil-SZ should not exceed 25 mg, and the frequency of use should be 1 time every 48 hours.
When used together with inhibitors of the cytochrome CYP3A4 isoenzyme (erythromycin, saquinavir, ketoconazole, itraconazole), the initial dose of Sildenafil-SZ should be 25 mg.
To minimize the risk of developing postural hypotension in patients taking alpha-blockers, Sildenafil-SZ should be started only after hemodynamic stabilization has been achieved in these patients. The advisability of reducing the initial dose of sildenafil should also be considered.
Side effects
The most common side effects were headache and flushing.
Typically, the side effects of Sildenafil-SZ are mild or moderate and transient.
Fixed-dose studies have shown that the incidence of some adverse events increases with increasing dose.
The frequency of adverse reactions is presented according to the following classification: very often (≥1/10%), often (from ≥1% to<10%), нечасто (от ≥0.1% до <1%), редко (от ≥0.01% до <0.1%), очень редко (<0.01%), частота неизвестна (невозможно определить на основе имеющихся данных).
From the immune system: uncommon - hypersensitivity reactions (including skin rash), allergic reactions.
From the hematopoietic system: infrequently - anemia, leukopenia.
Metabolism and nutrition: uncommon - feeling of thirst, edema, gout, uncompensated diabetes mellitus, hyperglycemia, peripheral edema, hyperuricemia, hypoglycemia, hypernatremia.
From the side of the organ of vision: often - blurred vision, blurred vision, cyanopsia; uncommon - eye pain, photophobia, photopsia, chromatopsia, redness of the eyes/scleral injections, changes in the brightness of light perception, mydriasis, conjunctivitis, hemorrhage in the eye tissue, cataracts, disruption of the lacrimal apparatus; rarely - swelling of the eyelids and adjacent tissues, a feeling of dryness in the eyes, the presence of rainbow circles in the field of vision around the light source, increased eye fatigue, seeing objects in yellow (xanthopsia), seeing objects in red (erythropsia), conjunctival hyperemia, irritation of the mucous membrane membranes of the eyes, discomfort in the eyes; frequency unknown - non-arteritic anterior ischemic optic neuropathy, retinal vein occlusion, visual field defect, diplopia*, temporary loss of vision or decreased visual acuity, increased intraocular pressure, retinal edema, retinal vascular disease, vitreous detachment/vitreal traction.
On the part of the hearing organ: uncommon - sudden decrease or loss of hearing, tinnitus, ringing in the ears, ear pain.
From the nervous system: very often - headache; often - dizziness; uncommon - drowsiness, migraine, ataxia, hypertonicity, neuralgia, neuropathy, paresthesia, tremor, vertigo, symptoms of depression, insomnia, unusual dreams, increased reflexes, hypoesthesia; rarely - convulsions*, repeated convulsions*, fainting, cerebrovascular accident, transient ischemic attack.
From the cardiovascular system: often - "tides"; uncommon - tachycardia, palpitations, decreased or increased blood pressure, increased heart rate, unstable angina, AV block, myocardial infarction, cerebral thrombosis, cardiac arrest, heart failure, abnormal ECG readings, cardiomyopathy; rarely - atrial fibrillation, sudden cardiac death*, ventricular arrhythmia*.
From the respiratory system: often - nasal congestion; uncommon - nosebleeds, rhinitis, asthma, dyspnea, laryngitis, pharyngitis, sinusitis, bronchitis, increased volume of sputum, increased cough; rarely - a feeling of tightness in the throat, dryness of the nasal mucosa, swelling of the nasal mucosa.
From the digestive system: often - nausea, dyspepsia; uncommon - gastroesophageal reflux disease, vomiting, abdominal pain, dry oral mucosa, glossitis, gingivitis, colitis, dysphagia, gastritis, gastroenteritis, esophagitis, stomatitis, abnormal liver function tests, rectal bleeding; rarely - hypoesthesia of the oral mucosa.
From the musculoskeletal system: often - back pain; uncommon - myalgia, pain in the limbs, arthritis, arthrosis, tendon rupture, tenosynovitis, bone pain, myasthenia gravis, synovitis.
From the urinary system: uncommon - cystitis, nocturia, urinary incontinence, hematuria.
From the genital organs and breast: uncommon - enlarged mammary glands, impaired ejaculation, swelling of the genitals, anorgasmia, hematospermia, damage to penile tissue; rarely - prolonged erection and/or priapism, bleeding from the penis.
For the skin and subcutaneous tissues: uncommon - skin rash, urticaria, herpes simplex, itching, increased sweating, skin ulceration, contact dermatitis, exfoliative dermatitis; frequency unknown - Stevens-Johnson syndrome, toxic epidermal necrolysis.
Others: uncommon - feeling of heat, swelling of the face, photosensitivity reaction, shock, asthenia, increased fatigue, pain of various localizations, chills, occasional burning, pain in the chest, accidental injuries; rarely irritability.
* Side effects identified during post-marketing studies.
During post-marketing use of sildenafil for the treatment of erectile dysfunction, adverse events such as severe cardiovascular complications (including myocardial infarction, unstable angina, sudden cardiac death, ventricular arrhythmia, hemorrhagic stroke, hypertension and hypotension) were reported, which had temporary association with the use of sildenafil. Most of these patients, but not all of them, had risk factors for cardiovascular complications. Many of these adverse events occurred shortly after sexual activity, and some of them occurred after taking sildenafil without subsequent sexual activity. It is not possible to establish a direct connection between the observed adverse events and these or other factors.
Visual impairment
In rare cases, during post-registration use of all PDE5 inhibitors, incl. sildenafil, non-arteritic anterior ischemic optic neuropathy (NAIOPN), a rare disease and cause of decreased or loss of vision, has been reported. Most of these patients had risk factors, including decreased papilledema/disc ratio (“congestive disc”), age over 50 years, diabetes mellitus, hypertension, coronary artery disease, hyperlipidemia, and smoking. An observational study assessed whether recent use of the PDE5 inhibitor class of drugs was associated with acute onset of NPINSID. Results indicate an approximately two-fold increase in the risk of NPINSID within 5 half-lives of PDE5 inhibitor use. According to the published literature, the annual incidence of NPINSID is 2.5-11.8 cases per 100,000 men aged ≥50 years in the general population. In case of sudden loss of vision, patients should be advised to stop sildenafil therapy and consult a doctor immediately. Individuals who have already had a case of NPIND have an increased risk of recurrent NPIND. Therefore, the physician should discuss this risk with such patients, as well as discuss with them the potential for adverse effects from PDE5 inhibitors. PDE5 inhibitors, incl. sildenafil should be used with caution in such patients and only in situations where the expected benefit outweighs the risk.
When using the drug Sildenafil-SZ in doses exceeding the recommended ones, adverse events were similar to those noted above, but usually occurred more often.
Overdose
Symptoms: with a single dose of Sildenafil-SZ in a dose of up to 800 mg, adverse events were comparable to those when taking the drug in lower doses, but were more common.
Treatment: carrying out symptomatic therapy. Hemodialysis does not accelerate the clearance of sildenafil, because the latter actively binds to plasma proteins and is not excreted by the kidneys.
Drug interactions
The influence of other drugs on the pharmacokinetics of sildenafil
The metabolism of sildenafil occurs mainly under the influence of the cytochrome isoenzymes CYP3A4 (the main pathway) and CYP2C9, therefore inhibitors of these isoenzymes can reduce the clearance of sildenafil, and inducers, accordingly, increase the clearance of sildenafil. A decrease in the clearance of sildenafil was noted with simultaneous use of inhibitors of the cytochrome CYP3A4 isoenzyme (ketoconazole, erythromycin, cimetidine). Cimetidine (800 mg), a nonspecific inhibitor of the cytochrome CYP3A4 isoenzyme, when taken together with sildenafil (50 mg), causes an increase in plasma sildenafil concentrations by 56%. A single dose of sildenafil in a dose of 100 mg together with erythromycin (500 mg 2 times a day for 5 days), a specific inhibitor of the cytochrome CYP3A4 isoenzyme, while achieving a constant concentration of erythromycin in the blood, leads to an increase in the AUC of sildenafil by 182%.
When taking sildenafil (single 100 mg) and saquinavir (1200 mg/day 3 times/day), an inhibitor of HIV protease and the cytochrome CYP3A4 isoenzyme, while achieving a constant concentration of saquinavir in the blood, the Cmax of sildenafil increased by 140%, and the AUC increased by 210%. Sildenafil has no effect on the pharmacokinetics of saquinavir.
Stronger inhibitors of the cytochrome CYP3A4 isoenzyme, such as ketoconazole and itraconazole, may cause more severe changes in the pharmacokinetics of sildenafil.
The simultaneous use of sildenafil (100 mg once) and ritonavir (500 mg 2 times a day), an HIV protease inhibitor and a strong cytochrome P450 inhibitor, while achieving a constant concentration of ritonavir in the blood leads to an increase in sildenafil Cmax by 300% (4 times). times), and AUC by 1000% (11 times). After 24 hours, the concentration of sildenafil in the blood plasma is about 200 ng/ml (after a single dose of sildenafil alone - 5 ng/ml), which is consistent with information about the pronounced effect of ritonavir on the pharmacokinetics of various cytochrome P450 substrates. Sildenafil has no effect on the pharmacokinetics of ritonavir. The combined use of sildenafil with ritonavir is not recommended.
A single dose of an antacid (magnesium hydroxide/aluminum hydroxide) does not affect the bioavailability of sildenafil.
Inhibitors of the cytochrome CYP2C9 isoenzyme (tolbutamide, warfarin), the cytochrome CYP2D6 isoenzyme (selective serotonin reuptake inhibitors, tricyclic antidepressants), thiazide and thiazide-like diuretics, ACE inhibitors and calcium antagonists do not affect the pharmacokinetics of sildenafil.
Azithromycin (500 mg/day for 3 days) has no effect on the AUC, Cmax, Tmax, elimination rate constant and T1/2 of sildenafil or its main circulating metabolite.
Effect of sildenafil on other drugs
Sildenafil is a weak inhibitor of cytochrome P450 isoenzymes -1A2, 2C9, 2C19, 2D6, 2E1 and 3A4 (IC 50 >150 µmol). When sildenafil is taken at recommended doses, its Cmax is approximately 1 µmol, so it is unlikely that sildenafil could affect the clearance of substrates of these isoenzymes.
Sildenafil enhances the hypotensive effect of nitrates both with long-term use of the latter and when they are prescribed for acute indications. In this regard, the use of sildenafil in combination with nitrates or nitric oxide donors is contraindicated.
When co-administering the alpha-blocker doxazosin (4 mg and 8 mg) and sildenafil (25 mg, 50 mg and 100 mg) in patients with benign prostatic hyperplasia with stable hemodynamics, the average additional reduction in systolic/diastolic blood pressure in the supine position was 7 /7 mmHg art., 9/5 mm Hg. and 8/4 mm Hg, respectively, and in a standing position - 6/6 mm Hg, 11/4 mm Hg. and 4/5 mmHg, respectively. Rare cases of symptomatic postural hypotension, manifested in the form of dizziness (without fainting), have been reported in such patients. In selected sensitive patients receiving alpha-blockers, concomitant use of sildenafil may lead to symptomatic hypotension.
There were no signs of significant interaction with tolbutamide (250 mg) or warfarin (40 mg), which are metabolized by the cytochrome CYP2C9 isoenzyme.
Sildenafil (100 mg) does not affect the pharmacokinetics of HIV protease inhibitors, saquinavir and ritonavir, which are substrates of the cytochrome CYP3A4 isoenzyme, at their constant blood levels.
Sildenafil (50 mg) does not cause an additional increase in bleeding time when taken (150 mg).
Sildenafil (50 mg) does not enhance the hypotensive effect of ethanol in healthy volunteers with a maximum ethanol concentration in the blood of an average of 0.08% (80 mg/dL).
In patients with arterial hypertension, no signs of interaction between sildenafil (100 mg) and amlodipine were detected. The average additional reduction in blood pressure in the supine position is 8 mm Hg. (systolic) and 7 mm Hg. (diastolic).
The use of sildenafil in combination with antihypertensive drugs does not lead to additional side effects.
special instructions
To diagnose erectile dysfunction, determine its possible causes and select adequate treatment, it is necessary to obtain a complete medical history and conduct a thorough physical examination. Treatments for erectile dysfunction should be used with caution in patients with anatomical deformation of the penis (angulation, cavernous fibrosis, Peyronie's disease), or in patients with risk factors for the development of priapism (sickle cell anemia, multiple myeloma, leukemia).
Medicines intended to treat erectile dysfunction should not be prescribed to men for whom sexual activity is undesirable.
Sexual activity poses a certain risk in the presence of heart disease, so before starting any therapy for erectile dysfunction, the doctor should refer the patient for an examination of the condition of the cardiovascular system. Sexual activity is undesirable in patients with heart failure, unstable angina, myocardial infarction or stroke in the last 6 months, life-threatening arrhythmias, arterial hypertension (BP >170/100 mm Hg) or hypotension (BP<90/50 мм рт. ст.). В клинических исследованиях показано отсутствие различий в частоте развития инфаркта миокарда (1.1 на 100 человек в год) или частоте смертности от сердечно-сосудистых заболеваний (0.3 на 100 человек в год) у пациентов, получавших препарат Силденафил-СЗ, по сравнению с пациентами, получавшими плацебо.
Cardiovascular complications
During post-marketing use of sildenafil for the treatment of erectile dysfunction, adverse events such as serious cardiovascular events (including myocardial infarction, unstable angina, sudden cardiac death, ventricular arrhythmia, hemorrhagic stroke, transient ischemic attack, hypertension and hypotension) have been reported. ), which had a temporary association with the use of sildenafil. Most of these patients, but not all of them, had risk factors for cardiovascular complications. Many of these adverse events occurred shortly after sexual activity, and some of them occurred after taking sildenafil without subsequent sexual activity. It is not possible to establish a direct connection between the observed adverse events and these or other factors.
Hypotension
Sildenafil has a systemic vasodilating effect, leading to a transient decrease in blood pressure, which is not a clinically significant phenomenon and does not lead to any consequences in most patients. However, before prescribing Sildenafil-SZ, the physician should carefully assess the risk of possible undesirable manifestations of the vasodilating effect in patients with relevant diseases, especially against the background of sexual activity. Increased susceptibility to vasodilators is observed in patients with obstruction of the left ventricular outflow tract (aortic stenosis, hypertrophic obstructive cardiomyopathy), as well as with the rare syndrome of multiple system atrophy, manifested by severe dysregulation of blood pressure from the autonomic nervous system.
Since the combined use of sildenafil and alpha-blockers may lead to symptomatic hypotension in some sensitive patients, Sildenafil-SZ should be administered with caution to patients taking alpha-blockers. To minimize the risk of developing postural hypotension in patients taking alpha-blockers, Sildenafil-SZ should be started only after hemodynamic stability has been achieved in these patients. The advisability of reducing the initial dose of Sildenafil-SZ should also be considered. The physician should inform patients about what actions to take if symptoms of postural hypotension occur.
Visual impairment
Rare cases of anterior non-arteritic ischemic optic neuropathy have been reported as a cause of deterioration or loss of vision with the use of all PDE5 inhibitors, including sildenafil. Most of these patients had risk factors such as optic disc excavation, age over 50 years, diabetes mellitus, hypertension, coronary artery disease, hyperlipidemia, and smoking. A cause-and-effect relationship between the use of PDE5 inhibitors and the development of anterior non-arteritic ischemic optic neuropathy has not been identified. The physician should inform the patient about the increased risk of developing anterior non-arteritic ischemic optic neuropathy if this condition has already been noted. In case of sudden loss of vision, patients should receive the necessary medical attention immediately. A small number of patients with hereditary retinitis pigmentosa have genetically determined dysfunction of retinal phosphodiesterases. There is no information on the safety of using Sildenafil-SZ in patients with retinitis pigmentosa, so sildenafil should be used with caution.
Hearing impairment
Some post-marketing and clinical studies have reported cases of sudden deterioration or loss of hearing associated with the use of all PDE5 inhibitors, including sildenafil. Most of these patients had risk factors for sudden deterioration or loss of hearing. A cause-and-effect relationship between the use of PDE5 inhibitors and sudden hearing loss or deterioration has not been established. If there is a sudden deterioration in hearing or hearing loss while taking sildenafil, you should consult your doctor immediately.
Bleeding
Sildenafil enhances the antiplatelet effect of sodium nitroprusside, a nitric oxide donor, on human platelets in vitro. There are no data on the safety of sildenafil in patients with a tendency to bleeding or exacerbation of gastric and duodenal ulcers, so Sildenafil-SZ should be used with caution in these patients. The incidence of epistaxis in patients with PH associated with diffuse connective tissue diseases was higher (sildenafil 12.9%, placebo 0%) than in patients with primary pulmonary hypertension (sildenafil 3%, placebo 2.4%). In patients receiving sildenafil in combination with a vitamin K antagonist, the incidence of epistaxis was higher (8.8%) than in patients not taking a vitamin K antagonist (1.7%).
Use in conjunction with other means of treating erectile dysfunction.
The safety and effectiveness of using Sildenafil-SZ in combination with other drugs for the treatment of erectile dysfunction have not been studied, so the use of such combinations is not recommended.
Impact on the ability to drive vehicles and operate machinery
While taking sildenafil, no negative effects on the ability to drive a car or use other technical equipment were observed.
However, since when taking sildenafil, a decrease in blood pressure, the development of chromatopsia, blurred vision and other side effects is possible, you should be careful about the individual effect of the drug in these situations, especially at the beginning of treatment and when changing the dosage regimen.
Pregnancy and lactation
Since the elimination of sildenafil is impaired in patients with liver damage (particularly with cirrhosis), the dose of Sildenafil-SZ should be reduced to 25 mg.Use in old age
No dose adjustment of Sildenafil-SZ is required in elderly patients.
Conditions for dispensing from pharmacies
The drug is available with a prescription.
Storage conditions and periods
The drug should be stored out of the reach of children, protected from light at a temperature not exceeding 25°C. Shelf life - 3 years.