It may be difficult to remain firm despite wanting to have sex. Based upon measurements of sildenafil in semen of healthy volunteers 90 minutes after dosing, less than 0. It is not recommended for use in Australia. The pharmacokinetics of sildenafil are dose-proportional over the recommended dose range. You’ll also need to fill out a medical questionnaire with answers about your medical history, current medications, and lifestyle habits. Do not start these medications while taking sildenafil without discussing it with your healthcare provider. If approved, the provider will issue a prescription.Sildenafil (Viagra) is a medicine used to treat erectile dysfunction (ED, also called impotence). Sildenafil works by helping to relax the blood vessels in the penis, allowing more blood to flow in and cause an erection. You should take sildenafil about an hour before planned sexual activity, so it has time to work. The Savings Offer and Program expire on 12/31/ For further information, call , visit test1.ru, or write: Viatris Inc., P.O. Box , Mission, KS Eligible patients may save on their VIAGRA® (sildenafil citrate) prescription with the VIAGRA savings card.  · Maximum dose: 20 mg orally three times a day. Injection: Initial dose: or 10 mg IV bolus three times a day. Comments: No greater efficacy was achieved with oral doses higher than the maximum recommended dose. A 10 mg injection dose is predicted to provide pharmacological effect equivalent to the 20 mg oral dose.