Topic Overview

What is capsaicin?

Capsaicin is the ingredient found in different types of hot peppers, such as cayenne peppers, that makes the peppers spicy hot. You can eat it in raw or cooked peppers or as a dried powder, which you can add to food or drinks. It also is available as a dietary supplement, in topical creams that you apply to your skin, or in a prescription skin patch.

What is capsaicin used for?

Capsaicin is used to help relieve pain. Capsaicin works by first stimulating and then decreasing the intensity of pain signals in the body. Although pain may at first increase, it usually decreases after the first use. Capsaicin stimulates the release of a compound believed to be involved in communicating pain between the nerves in the spinal cord and other parts of the body.

Topical use

When you apply capsaicin cream, gel, lotion, or ointment to the skin (topical use), it may help relieve pain from:

• Pain disorders, including pain after surgery.
• Nervous system problems such as diabetic neuropathy, trigeminal neuralgia, and postherpetic neuralgia (shingles).
• Cluster headaches.
• Joint problems such as osteoarthritis and rheumatoid arthritis.
• Skin conditions such as psoriasis.
• Mouth sores due to chemotherapy or radiation.

You can put products that contain capsaicin on your skin up to 4 times a day. You may feel a burning or itching sensation the first few times you use capsaicin, but this will gradually decrease with each use. Wash your hands thoroughly after each use to avoid getting capsaicin in your eyes or on other moist mucous membranes, where it can cause a burning sensation. Do not use capsaicin on areas of broken skin.

A high-dose skin patch is available by prescription (Qutenza). The patch is used to treat nerve pain from postherpetic neuralgia. It must be put on and removed by a doctor or nurse. The patch is left on the skin only for an hour or less, but the capsaicin continues to relieve pain after the patch is removed.

Supplement use

When you eat hot peppers or take capsaicin as a dietary supplement, the capsaicin may improve your digestion by increasing the digestive fluids in the stomach and by fighting bacteria that could cause an infection. It may also help fight diarrhea caused by bacterial infection.

Capsaicin acts as an antioxidant, protecting the cells of the body from damage by harmful molecules called free radicals. Capsaicin also may help prevent bacterial infections.

Capsaicin may also make mucus thinner and help move it out of the lungs. It is also thought to strengthen lung tissues and help to prevent or treat emphysema.

Is capsaicin safe?

Experts in the United States generally consider capsaicin to be safe. But it can cause some unpleasant effects, especially for those who are not used to it. Be careful when you cook with or eat hot peppers. Begin with small amounts, and increase the amount as you get used to it.

An allergic reaction to capsaicin is possible. If you are just beginning to use capsaicin, either as fresh or prepared food or in powder form, start with small amounts. If you use a topical product that contains capsaicin, you should first apply it to a small area of skin to test for an allergic reaction.

To reduce the burning sensation, remove the seeds from the peppers before you eat or cook with them. Also, if you eat bananas along with the peppers, you may reduce the burning sensation.

Don’t let capsaicin come into contact with your eyes and other moist mucous membranes. After you touch capsaicin (or hot peppers), use vinegar or soap to wash your hands so you don’t accidentally spread capsaicin to your eyes, nose, or mouth. You can also use disposable gloves to handle hot peppers or to apply topical products that contain capsaicin.

Do not apply topical products that contain capsaicin to areas of broken skin.

The U.S. Food and Drug Administration (FDA) does not regulate dietary supplements in the same way it regulates medicines. A dietary supplement can be sold with limited or no research on how well it works.

Always tell your doctor if you are using a dietary supplement or if you are thinking about combining a dietary supplement with your conventional medical treatment. It may not be safe to forgo your conventional medical treatment and rely only on a dietary supplement. This is especially important for women who are pregnant or breastfeeding.

When using dietary supplements, keep in mind the following:

• Like conventional medicines, dietary supplements may cause side effects, trigger allergic reactions, or interact with prescription and nonprescription medicines or other supplements you might be taking. A side effect or interaction with another medicine or supplement may make other health conditions worse.
• The way dietary supplements are manufactured may not be standardized. Because of this, how well they work or any side effects they cause may differ among brands or even within different lots of the same brand. The form of supplement that you buy in health food or grocery stores may not be the same as the form used in research.
• Other than for vitamins and minerals, the long-term effects of most dietary supplements are not known.