To date, there are only three FDA-approved drugs to treat erectile dysfunction (ED). The drugs Viagra, Cialis and Levitra work by increasing the flow of blood to the penis so that when a man is sexually stimulated, he can get an erection. All three drugs take approximately 15-30 minutes to take effect, but how long the drugs last varies.
Viagra typically lasts about four hours; Levitra about five hours; and Cialis can work up to 36 hours. These drugs must be prescribed by a doctor and are not suitable for everyone with erectile dysfunction. Your doctor will determine if you have ED and will decide if one of these drugs is right for you.
Men who have suffered a heart attack, stroke, or arrhythmia (irregular heartbeat) should not take ED drugs, and if you have uncontrolled low or high blood pressure or have chest pain during sex, you should avoid these drugs.
Some of the common side effects include headache, heartburn, flushing, nasal congestion, changes in vision, and back pain. More serious adverse effects and ones that require immediate medical attention are rash, painful erection, prolonged erection, fainting, chest pain, and itching/burning during urination. Blindness has been reported in several cases of men taking Viagra. Please see the August 6, 2007 blog entry entitled, “Viagra Linked to Blindness” to learn more about this.