As with sildenafil, a high-fat meal or alcohol keep the body from absorbing it as quickly. More serious side effects may include a drop in blood pressure or an erection that lasts longer than four hours. It’s best to check your chosen provider’s site for more information. However, all medications come with risks. Oral medicines for ED usually work well and cause few side effects.DRUG_DESCRPTION Compare DRUG_NAME prices and find coupons that could save you up to 80% instantly at pharmacies near you such as CVS, Walgreens, Walmart, and . Sildenafil (Viagra). Tadalafil (Cialis). Vardenafil. These medicines are called PDE5 inhibitors. They enhance the effects of a chemical the body makes that relaxes muscles . atherosclerosis.