Lemonaid can prescribe sildenafil generic Viagra , tadalafil generic Cialis , and vardenafil generic Levitra. More serious side effects may include a drop in blood pressure or an erection that lasts longer than four hours. Your primary care doctor should always know what medications you’re taking, including ED pills prescribed by another provider. If you have an erection that lasts more than 4 hours, get medical help right away. It’s available in 50 mg, mg, and mg tablets. If it is not treated right away, priapism can permanently damage your penis sudden vision loss in one or both eyes.According to price-comparison site , generic Revatio will cost you as little as $ per pill, depending on where you fill your prescription. That’s . CHOOSE BRAND-NAME VIAGRA. The original little blue pill prescribed by doctors for over 20 years. Clinically proven to treat men with erectile dysfunction (ED) Ongoing . 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 adult .