Medication Description: Sildenafil Citrate (Sildenafil citrate)
SILDENAFILA CITRAT (Sildenafil citrate).
Citrate 1 - [[3- (6,7-Dihydro-1-methyl-7-oxo-3-propyl-1H-pyrazolo [4,3-A] pyrimidin-5-yl) 4-ethoxyphenyl] sulfonyl] piperazine.
Synonym: Viagra, Viagra.
It was originally proposed as a cardiovascular agent, but was not effective enough; however, some male patients receiving it noted an increase in sexual potency; the drug was studied in this direction, the data was confirmed and sildenafil (called "Viagra") received medical use.
The mechanism of action is still not clear enough. From the point of view of biochemistry, the main importance is currently attached to the ability of sildenafil to selectively inhibit the activity of the type V phosphodiesterase enzyme, which inactivates cyclic guanosine monophosphate (c-GMP), which is involved in relaxing the smooth muscles of the cavernous body and improving blood supply to the penis. Sildenafil does not have a direct relaxing effect on the vessels of the cavernous body, but it enhances the vasodilating effect released by sexual stimulation of nitric oxide (NO) in relation to this tissue. Obviously, spinal cord stimulation plays a physiological role, especially in light of data on the efficacy of the drug for potency disorders associated with lesions of the spinal cord.
When ingestion is quickly and completely absorbed, bioavailability is 40%, Cmax - 60 min, T1 / 2 - 4 h; subjected to intense biotransformation in the liver with the formation of the active metabolite, displayed mainly with feces in the form of metabolites.
Assign inside (in the form of tablets), usually at a dose of 0.05 g (50 mg) for 1 hour before sexual intercourse. Depending on the effect, the dose can be reduced to 0.025 g or increased to 0.1 g. The maximum recommended dose is 0.1 g 1 time per day.
According to reports, the drug is usually well tolerated. Possible side effects: headache, dizziness, dyspepsia, dilatation of peripheral vessels (hot flashes), impaired light and color perception, clarity of vision, arthralgia and myalgia.
The drug is contraindicated in severe somatic diseases.
Cardiologists draw attention to the danger of the use of the drug by patients using nitrates (that is, a wide range of patients suffering from coronary artery disease). In recent information materials, nitrate intake refers to contraindications for the appointment of Viagra. Endocrinologists recommend that patients with diabetes consult a cardiologist and an ophthalmologist. In general, it is advisable to use the drug on the advice of a doctor.
Form release: pills to 0.025; 0.05 and 0.1 g (25; 50 and 100 mg) (N. 1, 4, 8, 12).