This boosts blood flow and helps you get an erection from sexual activity. Kidney disease that needs to be treated with dialysis. The body takes longer to absorb it after a high-fat meal or alcohol. An inherited eye disease that affects the retina. Generic versions of sildenafil, vardenafil and tadalafil are available. Often, these are prescribed for chest pain called angina.tadalafil or cialis Savings, Coupons and Information. | TADALAFIL (tah DA la fil) treats erectile dysfunction (ED). It works by increasing blood flow to the penis, which helps to maintain an erection. The price of tadalafil may depend on the strength. Tadalafil comes in strengths of milligrams (mg), 5 mg, 10 mg, and 20 mg. As with other drugs, the cost of tadalafil depends on several factors. 1 day ago · In addition to Viagra, REX MD also offers brand-name Cialis and generic Cialis (tadalafil). Both Viagra and sildenafil are available in mg, mg, and mg doses.