Viagra, Levitra, and Cialis are oral medications that are used to treat erectile dysfunction. They work by increasing the flow of blood into the penis, so that a man can get an erection when he is sexually stimulated.
There are certain situations in which these medications may not be safe to take. Before taking these medications, tell your doctor:
- If you are allergic to these medications or any other drugs.
- About any prescription or nonprescription medications you are currently taking, including herbal and dietary supplements.
- If you take nitroglycerin or a long-acting nitrate to treat chest pain. The combination of these drugs with nitrates can cause dangerously low blood pressure.
Also, tell your doctor if you have ever had any of the following:
- Heart disease
- Heart attack
- Angina (chest pain associated with heart disease)
- Stroke
- Retinitis pigmentosa (a rare disease of the eye that causes vision loss)
If you have any of these conditions, these medications may not be safe for you to take. Your doctor can explain the risks and benefits of taking the drug based on your medical history and can recommend other treatment options.
How should these medications be used?
They should be taken about 30 to 60 minutes before sexual activity. They will not work unless the man receives sexual stimulation.
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 medications 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 medications more than once a day.
What are the side effects of these medications?
Side effects are not common but they can occur. Side effects can include:
- Headache
- Upset stomach
- Flushing (feeling warm)
- Nasal congestion
- Changes in vision
- Prolonged erections
Call your doctor if you experience severe forms of these symptoms or if they do not go away after 4 to 8 hours.
Warning
Call your doctor immediately if you experience any of the following symptoms:
- Rash
- Painful erection
- Prolonged erection (longer than 4 hours)
- Fainting
- Chest pain
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 2/5/2007...#10049
