Stendra avanafil : This is an as-needed medication taken 30 minutes before sex and can last up to six hours. More serious side effects may include a drop in blood pressure or an erection that lasts longer than four hours. Please expect up to 4 to 6 weeks for reimbursement. If you prefer, you may contact the U. Payment options: Consider how you’d like to pay.VIAGRA is available by prescription only in 25 mg, 50 mg, and mg tablets. Patients should always ask their doctors for medical advice about adverse events. You are . The cost for sildenafil oral tablet mg is around $10 for a supply of 2 tablets, depending on the pharmacy you visit. Quoted prices are for cash-paying customers and are not . Sildenafil (Viagra) is a phosphodiesterase-5 (PDE-5) inhibitor. PDE-5 is a protein in your body that breaks down the molecules that normally cause an erection. When it blocks .