Sildenafil is indicated for the treatment of erectile dysfunction.

Drugs for Erectile Dysfunction

Sildenafil is a selective inhibitor of cyclic Guanosine Monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5) used for treatment of erectile dysfunction. Danafil (Sildenafil) enhances the effect of nitric oxide (NO) by inhibiting phosphodiesterase type 5 (PDE5), which is responsible for degradation of cGMP in the corpus cavernosum that results in smooth muscle relaxation and inflow of blood to the corpus cavernosum.

The recommended dose of Sildenafil is 50 mg taken approximately 1 hour before sexual activity. However, Sildenafil may be taken anywhere from half an hour to 4 hours before sexual activity. Based on effectiveness and toleration, the dose may be increased to a maximum 100 mg or decreased to 25 mg. The maximum recommended dosing frequency is once per day.

Sildenafil may takes longer time to work if you take it with a heavy meal.

Concomitant use of Sildenafil with organic nitrates for angina may cause hypotension. Cimetidine, a medicine used to treat gastric ulcers, some antibiotics including Erythromycin and Rifampicin, some protease inhibitors such as Ritonavir and Saquinavir for the treatment of HIV infection may increase the plasma concentration of Sildenafil. Some medicines used to treat fungal infections including Ketoconazole and Itraconazole may reduce the clearance of Sildenafil.

Sildenafil is contraindicated in patient with hypersensitivity to any component of this medication. Sildenafil potentiates the hypotensive effects of nitrates, so it is contraindicated in patients who are using organic nitrates, either regularly or intermittently.

The adverse effects treated with Sildenafil are headache, flushing, dyspepsia, nasal congestion, urinary tract infection, abnormal vision, diarrhea, dizziness and rash.

Pregnancy category B. There are no adequate and well-controlled studies of Sildenafil in pregnant women. Sildenafil is not indicated for use by women. In animal study shows that Sildenafil has no evidence of teratogenicity or embryotoxicity.

Caution should be exercised if patients have any allergies to any other medicines or any other substances such as foods, preservatives or dyes, heart or blood vessel problems, sudden loss of eyesight in one or both eyes. Caution should be taken if patients have any of the following medical conditions such as diabetes, kidney or liver problems, leukaemia, multiple myeloma, any disease or deformity of penis, any bleeding disorder such as haemophilia, stomach ulcer, sickle cell anaemia, color vision problems, sudden decrease or loss of hearing or receiving any other treatment for impotence.

Keep in a dry place, away from light and heat. Keep out of the reach of children.