Disclaimer: We use affiliate links in this article and may earn a commission from it. Next review due on August 01, Erectile dysfunction can often be traced to the same causes as cardiovascular disease, including inflammation, a narrowing of the arteries, or a hardening of the arteries. Popular ED medications found online include: Viagra sildenafil : As the first FDA-approved PDE5 inhibitor for ED, sildenafil is taken 30 minutes to four hours before sexual intercourse to help achieve and maintain an erection. Free Viagra samples are frequently offered for a brief period of time and can be requested via online forms or by getting in touch with the business. This medication is taken with or without food an hour before sex.Learn More IF YOU CHOOSE BRAND-NAME VIAGRA, MAKE SURE YOU GET THE BRAND NAME Your prescription may have been filled with a generic version instead of brand-name VIAGRA. Follow the steps below to help ensure you receive the brand name your doctor prescribed and, if eligible, save on your prescription. Ask Your Doctor. A Florida man has been charged with several felonies and a misdemeanor after police say he threatened a CVS pharmacy, asking for “all bottles” of Viagra, Adderall and other drugs. Generic name: sildenafil (oral) [ sil-DEN-a-fil ] Brand names: Revatio, Viagra Drug class: Impotence agents Medically reviewed by Sophia Entringer, PharmD. Last updated on Uses Warnings Before taking Dosage Side effects Interactions FAQ What is Viagra?