Keep from freezing. Though this growth is not cancerous, prostate cancer and BPH can co-occur. Your doctor may adjust your dose if needed. Continue to take sildenafil even if you feel well. The results showed the combination to be even more effective than either medication alone. Alpha-blockers are sometimes prescribed for prostate problems or high blood pressure.This means that 4 hours after you take a dose, your body has cleared half of the dose. In most cases, it takes about 5 half-lives for your body to completely remove a drug from your system. So. Sildenafil oral tablet is available as a brand-name drug and as a generic drug. Brand names: Viagra, Revatio. Sildenafil comes in three forms: an oral tablet, an oral suspension (liquid), and an. Brand names for sildenafil include Viagra, Revatio, and Liqrev. The cost for sildenafil oral tablet mg is around $10 for a supply of 2 tablets, depending on the pharmacy .