Levitra 5 mg is used to treat Erection dysfunction (impotence) that relaxes muscles found in the walls of blood vessels and increases blood flow to particular areas of the body. According to your doctor’s advice, you should take the medication as a whole with a glass of water 30 minutes before sexual activity. Taking this medication with certain other medicines can cause a sudden and serious decrease in blood pressure. Do not take Levitra with a drug of nitrate for chest pain or heart problems. You should never take a double dose of the medication within 24 hours which may be life-threatening.