Sildenafil may cause side effects. The following information includes only the average doses of this medicine. These medicines all work well for ED. Talk to your doctor or consult a mental health provider to address these issues. Is my erectile dysfunction most likely temporary or chronic? If you have an erection that lasts more than 4 hours, get medical help right away. Communicate openly and honestly about your condition.AdSay Goodbye to Performance Anxiety and Hello to Improved Sexual Stamina! Reviews and Comparisons Of The Best Male Enhancement Products. See Which Products test1.ru 20 Years Online · Over Products Tested · Honest & Unbiased Reviews. Sildenafil (Viagra brand) increases blood flow to the penis following sexual stimulation. It does this by blocking the enzyme responsible for the breakdown of cGMP. cGMP is a substance that relaxes and widens blood vessels and smooth muscle cells. This allows men to keep an erection hard enough for sex. AdNeed Safe and Affordable Medicine? test1.ru is here to help you!