Take sildenafil as needed before sexual activity. Although the interaction between other protease inhibitors and sildenafil has not been studied, their concomitant use is expected to increase sildenafil levels. If you have certain health conditions or are taking certain medications, your doctor may tell you to take sildenafil less often. Do not take a double dose to make up for a missed one. Other uses for this medicine This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information. It lasts 4 to 5 hours, or longer if you have mild to moderate ED. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule.Men will no longer require a prescription to obtain the impotence drug Viagra and will instead be able to buy it over the counter at pharmacies. The decision by the UK Medicines and Healthcare. Tell all your healthcare providers that you take VIAGRA. If you need emergency medical care for a heart problem, it will be important for your healthcare provider to know when you last took VIAGRA. Tell your healthcare provider about all the medicines you take 1, including prescription and over-the-counter medicines, vitamins, . The Savings Offer and Program expire on 12/31/ For further information, call , visit , or write: Viatris Inc., P.O. Box , Mission, KS Eligible patients may save on their VIAGRA® (sildenafil citrate) prescription with the VIAGRA savings card.