Stendra avanafil : This is an as-needed medication taken 30 minutes before sex and can last up to six hours. You should also call your insurance company to see if they cover erectile dysfunction medications. Finding an online ED provider can feel overwhelming. According to the FDA, generic medications contain the same active ingredients as brand names, meaning there’s no difference in effectiveness or safety. Here are some key factors to consider when deciding: Pricing: Know how much your monthly supply will cost with shipping and tax. When taken at the correct time and paired with sexual stimulation, the erection lasts long enough for successful intercourse.Sildenafil (Viagra). This medicine works best when you take it on an empty stomach an hour before sex. The body takes longer to absorb it after a high-fat meal or .  · Sildenafil under the name Viagra is used to treat erectile dysfunction (impotence) in men. Another brand of sildenafil is Revatio, which is used to treat .  · Best subscription service for Viagra and generic Viagra: Rex MD Viagra Although erectile dysfunction (ED) may be an upsetting diagnosis for some, many people .