These small differences affect the way each medication works, such as how quickly it takes effect and wears off, and the possible side effects. Viagra generally only stays in your system for four to six hours. If you ever need emergency medical treatment for a heart problem, the healthcare providers who treat you will need to know when you last took sildenafil. This can happen if you are sick with fever, diarrhea, or vomiting; sweat a lot; or do not drink enough liquids. Use the oral syringe provided with your medication to measure and take your dose.According to price-comparison site test1.ru, generic Revatio will cost you as little as $ per pill, depending on where you fill your prescription. That’s compared with . Here’s what you can do. 1. Leave her alone. This may not be easy, so try to be patient. In the first two weeks, the bristles may look “spotty”, but take our word for it-it’s worth waiting a couple more weeks, and its appearance is likely to change for the better. A beard is a naughty thing, and at first every hair has its own life. Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. VIAGRA may affect the way other medicines work, and other medicines may affect the way VIAGRA works, causing side effects. Especially tell your healthcare provider if you take any of the following.