Viagra, known as the blue pill, can be prescribed by doctors or clinicians in strengths of 25mg, 50mg, and mg. This boosts blood flow and helps you get an erection from sexual activity. When choosing one, tell your doctor or other health care professional what your preferences are, such as cost, ease of use, how long the drug’s effects last and side effects. Clinical trials for MED found minimal side effects. Side effects Side effects of oral ED medicines are often mild. Kidney disease that needs to be treated with dialysis.FAQs What to consider Cost Overdose Ask your doctor Q&A Drug Images What is Viagra? If you have erectile dysfunction (ED), your doctor may recommend that you take Viagra. . Generic Viagra (sildenafil) is an alternative to the branded Viagra drug that can be used for treating erectile dysfunction (ED). It’s now sold by many manufacturers, including online. 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 pulmonary arterial .