Hay hombres que toman Viagra o alguna de los medicamentos similares de los que hablábamos antes, simplemente para durar más en el sexo o para conseguir erecciones más fuertes. También para reducir el periodo refractario, el tiempo que transcurre entre un orgasmo y la siguiente erección. La efectivid See more.Salió al mercado en y desde entonces ha sido utilizada por millones de hombres para resolver sus problemas de disfunción eréctil. Sildenafil is in a class of medications called phosphodiesterase PDE inhibitors. La efectividad es diferente dependiendo de la persona. These medicines prevent an enzyme called phosphodiesterase type-5 from working too quickly. Common ones include: Flushing of the skin.Examples of Viagra’s more commonly reported side effects include: heache. flushing (temporary warmth, redness, or deepening of skin color) stuffy nose. . Drug Images What is Viagra? If you have erectile dysfunction (ED), your doctor may recommend that you take Viagra. It’s a prescription drug that’s used in ult . Sildenafil is used to treat men who have erectile dysfunction (also called sexual impotence). Sildenafil belongs to a group of medicines called phosphodiesterase .This medicine works best when you take it on an empty stomach an hour before sex. Your doctor or other health care professional can recommend one for you based on these factors, other health conditions you have and any other medicines you take. When oral medications might not be safe Check with your health care team before you take any medicine for erectile dysfunction. If you are a Mayo Clinic patient, this could include protected health information. These include itraconazole Sporanox, Tolsura , ketoconazole Extina, Ketozole, others and ritonavir Norvir.