What Are the Differences Between Cialis, Levitra, and Viagra?

There are only three oral drugs approved by the FDA to treat erectile dysfunction: Cialis, Levitra, and Viagra. All work by increasing the flow of blood into the penis so that when a man is sexually stimulated, he can get an erection.

Cialis, Viagra and Levitra to Treat ED

Cialis, Levitra, and Viagra work by a similar mechanism to cause erections. There are subtle differences in how long the drug works and how quickly it works. Levitra works a little longer than Viagra. They both take effect in about 30 minutes. With Levitra, the effects last for about 5 hours. With Viagra, the effects last approximately 4 hours.

Cialis works a bit faster (within about 15 minutes), and the effects last much longer—up to 36 hours in some cases.

If One of These Drugs Isn’t Effective for Erectile Dysfunction, Can I Try Another?

Because these drugs work the same way, it’s unlikely that you’ll have success with one if you’ve failed to achieve an adequate erection with another.

What Precautions Should I Take Before Taking One of These Drugs?

There are certain situations in which these drugs may not be safe to take. Before taking them, tell your doctor:

• If you are allergic to Viagra or any other drugs.
• About any prescription or nonprescription medications you are currently taking, including herbal and dietary supplements.
• If you are scheduled for surgery, including dental surgery.
• If you take nitroglycerin or a long-acting nitrate to treat chest pain. The combination of Cialis, Levitra or Viagra with these drugs can cause dangerously low blood pressure.
• If you take alpha-blockers for blood pressure or prostate problems. The combination of Cialis or Levitra with these drugs can also cause dangerously low blood pressure.

In addition, always follow the directions on your prescription label carefully and ask your doctor or pharmacist to explain any part that you do not understand. Take these drugs exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor. Do not take these drugs more than once a day.

Who Should Not Take Cialis, Levitra or Viagra?

If you have suffered from a heart attack, stroke or life threatening arrhythmia (irregular heart rate) within the last 6 months you should discuss other options with your doctor. It is also advised to avoid these drugs if you have uncontrolled high or low blood pressure or if you experience chest pain with sex.