Your doctor or other health care professional can recommend one for you based on these factors, other health conditions you have and any other medicines you take. You can take this medicine with or without food 30 minutes before sex, depending on the dose. What Are the Symptoms of Erectile Dysfunction? Avanafil Stendra. Erectile dysfunction medications require a prescription from a licensed provider. Sildenafil Viagra. In some cases, online ED providers accept health insurance.Common Brands Viagra Drug Class PDE-5 inhibitor Controlled Substance Classification Not a controlled medication Generic Status Lower-cost generic available . Sildenafil (Viagra, Revatio) is a moderately priced drug used to treat erection problems in men. It is also used to treat pulmonary arterial hypertension, a serious heart and lung . Q&A Drug Images What is Viagra? If you have erectile dysfunction (ED), your doctor may recommend that you take Viagra. It’s a prescription drug that’s used in .