Viagra relaxes muscles found in the walls of blood vessels and increases blood flow to particular areas of the body. Viagra is used to treat erectile dysfunction (impotence) in men. Viagra is used to treat problems relating to male sexual function, particularly problems concerning the ability to achieve and maintain an erection. Learn how to take Viagra safely to treat erectile dysfunction. Swallow a 50 mg dose of Viagra 30-60 minutes before sex. Sildenafil is used to treat erectile dysfunction (also called sexual impotence). Sildenafil belongs to a group of medicines called phosphodiesterase 5 (PDE5) inhibitors. These medicines prevent an enzyme called phosphodiesterase type-5 from working too quickly. The penis is one of the areas where this enzyme works. Viagra (sildenafil) is a prescription-only medication used to help treat erectile dysfunction (ED) in men. Learn more about what Viagra is, including what it’s used for, how it works, side effects, potential drug interactions and the difference between Cialis vs Viagra. Evidence-based academic analysis of sildenafil citrate: mechanism, pharmacokinetics, clinical efficacy, and safety profile. Stop sexual activity and get medical help right away if you get symptoms such as chest pain, dizziness, or nausea during sex. Viagra is a medication used to treat erectile dysfunction by improving blood flow to the penis. The drug is available in different dosages. The appropriate dose depends on factors like age. Sildenafil (Viagra) is a tablet that's taken by mouth for erectile dysfunction (ED) in adults. It works as a phosphodiesterase-5 (PDE5) inhibitor to help people get an erection or keep an erection that lasts for sex. Learn more about Viagra, including its uses, dosage, side effects, and how to get it. There are several Food and Drug Administration (FDA)-approved ED pills available to treat the condition. No one pill is considered the most effective in all use cases. The best option for you will.