They can aid in deciding whether the drug is right for you and offer suggestions for dealing with any side effects. Depending on your needs and preferences, you have the option to take it either on an as-needed basis or daily if prescribed by your doctor. What should I do if I forget a dose? But during trials, doctors noticed it worked on HIV. Only 10 per cent of new drugs make it through trials, they often take 10 years, and cost 10 billion pounds. This allows enough time for the medication to kick in and start doing its thing.For men experiencing erectile dysfunction (ED), exercising regularly can be nearly as effective as ED medications, such as Viagra (sildenafil), in improving performance, according to a new meta. If you’re holding out for a generic version of branded Viagra, you won’t have to wait much longer. Teva Pharmaceuticals plans to release its generic of the “little blue pill” as early as.  · Agard is on point there, because Viagra is a prescription drug and prescription drugs aren’t taxed. Our ruling. Agard said, “Potato chips, Kit Kat bars and Viagra are not taxed in Wisconsin.