Description
Viagra
Viagra is the first and most studied drug for the treatment of erectile dysfunction. Given the proven effectiveness, ease of use, good tolerability, excellent safety profile, and positive impact on quality of life – Viagra is still among the best drugs for the pharmacotherapy of erectile dysfunction.
Prescribing Information
The therapeutic effect of Viagra in improving erectile function is based on the slowing down of the degradation of the cellular isoenzyme, which improves the blood supply to the penis.
Viagra helps to relax the smooth muscles of the penis, expand the blood vessels of the cavernous body and achieve an erection.
Viagra tablets, usedin the treatment of erectile dysfunction, can contain 25 mg, 50 mgor 100 mg of the active ingredient Sildenafil.
Dosage
The initial dose of Viagra is 25 mg once. If the erection is absent or the penis is not hard enough to perform an intercourse, the daily dose can be increased to 50 mgor 100 mg.
The therapeutic effect of Viagra is achieved approximately in 1 hour after the intake. Men can schedule sexual intercourse within 4 hours after the drug administration. 2more hours later, the erectile response of Viagra gradually decreases.
Interactions
The interaction of Viagra with organic nitrates leads to an unpredictable lowering in blood pressure and an increased risk of clinically manifested hypotension.
Such drugs as Clarithromycin, Ketoconazole, Erythromycin or Itraconazole inhibit the metabolism of Viagra and may increase the level of the drug in the blood. Therefore, the dosages of Clarithromycin, Ketoconazole, Erythromycin or Itraconazole should be reduced, when men use Viagra.
The interaction of Viagra with hypotensive drugs can lead to insignificant changes in blood pressure. In most cases, however, the profile of adverse effects of Viagra does not worsen, even if a man takes several antihypertensive drugs.
The intake of alcohol in moderate doses does not have any effect on the pharmacokinetics of Viagra. When Viagra interacts with ethanol, there is no change in cardiac output, heart rate, blood pressure, or peripheral vascular resistance. In other words, Viagra does not increase the hypotensive effect of alcohol.
Side effects
The most frequent side effect of Viagra is a headache, which is monophasic. That is, men do not experience emotional and physical sufferingafter the repeated administration of the medicine.
Viagra can affect the isoenzyme that is contained in the retina of the eye. Therefore, some men may have violations of color perception.
After the intake of Viagra, men may also experience blood flushes to the face, increased heart rate, abdominal pain, or diarrhea. However, all side effects are of a rolling nature and do not require withdrawal of therapy.
Tips
A few tips for improving the effectiveness and safety of the pharmacotherapy for erectile dysfunction with the help of Viagra:
- At the beginning of therapy, it is recommended to take Viagra on an empty stomach, at least 30 minutes before the planned commencement of sexual intercourse;
- Men with severe impairment of renal and hepatic function may require Viagra dose adjustment;
In some men, the maximum therapeutic effect of Viagra is achieved by the sixth to eighth intake.Taking into account this fact, the final evaluation of the effectiveness of the ED treatment should be made after using several doses of Viagra.