Levitra (vardenafil) is often prescribed for men that are unable to enjoy their sex life because of erection problems. Levitra is supposed to be taken about 60 minutes before having sex and is supposed to provide you with up to 5 hours of efficiency. This drug should not be taken if you are using nitrate-based medications, as otherwise a sudden drop in blood pressure is possible. Tell your health care provider if you are taking or are planning on taking rifampin, carbamazepine, HIV protease inhibitors, antifungals, fluvoxamine, phenobarbital, troleandomycin, other erectile dysfunction remedies, verapamil, delavirdine, irregular heartbeat meds, paroxetine, sertraline, isoniazid, phenytoin, alpha blockers, fluoxetine, clarithromycin, cimetidine, efavirenz, erythromycin, or medications for high blood pressure, as they are not supposed to be combined with Levitra without the consent of your health care professional. Taking more of Levitra cause the following symptoms: blurred vision, back pain or muscle pain. If you took too much of Levitra - seek emergency medical help even though the symptoms mentioned do not seem serious.