Mountains of "little blue pills" and their chemical kin have transformed the way many people think about sex and aging. Raphael Gaillarde/Gamma-Rapho/Getty Images hide caption

itoggle caption Raphael Gaillarde/Gamma-Rapho/Getty Images

If you're interested in buying Viagra, Pfizer, the drug's maker, will now sell it to you from its official website. William Vazquez/AP hide caption

itoggle caption William Vazquez/AP