That’s not to say there aren’t just as many illegitimate sites. Your health information should remain between your provider and yourself. Yes, ED pills can cause side effects. Other conditions that may disqualify you from an ED prescription include a history of stroke, kidney or liver disease, cancer, diabetes, or a bleeding disorder. Erectile dysfunction medications require a prescription from a licensed provider. These PDE5 inhibitors may cause headache, flushing, drop in blood pressure, or other adverse effects.Viagra. Compare prices and print coupons for Sildenafil (Generic Revatio and Viagra) and other drugs at CVS, Walgreens, and other pharmacies. Prices start at $ AdSave Time & Money with Online Prescription for Viagra, Cialis, Sildenafil and Tadafil. Free & Private Online Consultant with Real Doctors. Reliable E.D. Meds Shipped DiscreetlyK+ visitors in the past month. View all prices. Buy Viagra Online. Bye ED. For ED, Viagra is the first port of call. It’s been used by millions of men for over 20 years, and works by boosting circulation to the penis. .