Levitra (vardenafil) is a prescription medicine taken by men that are unable to have sex because of insufficient blood flow into the tissue of the penis. Any drugs that contain nitrates should not be taken along with Levitra. A dangerous reaction can occur if you combine these drugs together, so make sure you discuss with your health care provider any medicines you are taking at the moment for your treatment to be both safe and efficient. If you experience an erection lasting for longer than 4 hours make sure you report it to your health care provider. Other things that need to be mentioned when you are talking to your health care professional are your health conditions that may require some additional tests or you will be placed under your doctor's close supervision. These conditions include a history of a heart attack, bleeding disorder, Peyronie's disease, a history of a stroke, diabetes, a history of long QT or retinitis pigmentosa running in the family, chest pain, high cholesterol, blood cell problems, ulcers in the stomach, liver, kidney, or heart disease, high or low blood pressure, cavernosal fibrosis and a history of irregular heartbeat. Any herbal products you are taking at the moment must be reported to your doctor before you ask him for Levitra prescription. If you are having sex and experience dizziness, fainting and chest pain please stop taking Levitra and consult your health care provider as soon as possible, as these are very serious side effects.