Testoryze Reviews: "PDE5Is cannot yet be legally sold over the counter in this country," Terlecki said. And many of these products contain traces of an ingredient used in drugs like Viagra that can be dangerous to men with certain health problems, the researchers added. And there's plenty of debate on whether size matters at all. The most sensitive nerves in the vagina are found close to the surface, Lamm notes, and the clitoris is found on the vagina's outside. So there should be plenty of ways to satisfy your partner that have nothing to do with pills, creams, surgery, or devices.