Often, these are prescribed for chest pain called angina. Unless you have questions about your local pharmacy’s reputation, there should be no problem purchasing drugs from their sites. These pharmacies can work very well if it’s difficult for you to get to your local pharmacy. These small differences affect the way each medication works, such as how quickly it takes effect and wears off, and the possible side effects. This allows the smooth muscles in the penis to relax and fill with blood.Still, if your doctor says it’s okay for you to use and you end up paying out-of-pocket, you can still get the generic for a lot less than Viagra. According to price-comparison site. Medically reviewed by Sophia Entringer, PharmD. Last updated on Uses Warnings Before taking Dosage Side effects Interactions FAQ What is Viagra? Viagra . Stick to reputable sites and pharmacies you can trust. Is there an over-the-counter version of Viagra? Can I get Viagra online without seeing a doctor?