Viagra.

Viagra (sildenafil) is a very effective prescription drug used for the treatment of impotence in males of any age. It is taken 30 to 60 minutes before having sex and needs to be used in complete accordance with the recommendations of your doctor, as otherwise you may not benefit from the dose prescribed as much as you expected. Tell the doctor prescribing Viagra if you are taking any meds that can interfere with Viagra, such as alpha blockers, rifampin, rifabutin, other erectile dysfunction meds, seizure medications, HIV protease inhibitors, anticoagulants, barbiturates, efavirenz, medications for high blood pressure, bosentan, certain antifungals, amlodipine, erythromycin, nevirapine, cimetidine, or beta blockers. It's very important that you discuss your personal risks associated with the treatment and see if the benefits outweigh potential risks for you. Let your doctor know if you get any side effects that do not go away or persist. The following mild side effects are possible although they tend to go away on their own: warmth or redness in your face or chest, upset stomach, headache, stuffy nose, back pain, or memory problems.