What is it good for?
Muscle aches. The Eclectic School recommended peppers for “muscular rheumatism.” Tradition has it that capsicum is especially effective on painful muscle spasms in areas of shoulder, arm and spine. The mechanism by which capsaicin relieves pain is now beginning to be understood. Some of its effects are merely diversionary.224 The sensations on the skin take the mind away from pain deeper in the body. But the effects go beyond diversion to the neurological. When the body is continually exposed to capsaicin, sensory neurons are depleted of neurotransmitters. The cause of the pain remains, but the pain signal no longer reaches the brain because of the lack of neurotransmitters. The result is a reduction in sensation of pain. When the exposure is discontinued, the neurons recover and the pain returns if the cause of the pain is still present.225
Clinical studies have demonstrated this pain-relieving effect. In a study of low back pain, capsaicin cream decreased pain and increased mobility significantly better than a placebo.226 Another study showed similar benefits to low back pain from a capsaicin plaster.227 In 2007, surgeons began experimenting with an ultrastrong, ultrapurified (to avoid infection) capsaicin preparation. Volunteers had capsaicin introduced to surgical wounds to minimize postoperative pain.228 Similarly, the National Institutes of Health is experimenting with capsaicin for the severe pain of advanced cancer sufferers. Both of the 2007 studies are still in progress, and the jury is still out as to whether they will show benefit, but the fact that large-scale experiments are being conducted by major medical organizations shows a beginning acceptance on the part of Western medicine of capsaicin’s pain relieving properties.229 The FDA has approved over-the-counter capsaicin preparations for this use.
Relieving joint pain caused by injury or arthritis. The mechanism by which capsaicin alleviates joint pain when applied topically is the same as the way it relieves muscle pain. The 1918 U.S. Dispensatory recommends capsicum ointment (made from peppers, lard, and paraffin) as a counterirritant for sprains, bruises, and rheumatism. Topical application reduces pain and swelling from arthritis in rats.230 In a human trial, however, it provided no pain relief for sufferers of TMJ.231 One study found help for osteoarthritis but no help for rheumatoid arthritis.232 Another found reduction in knee pain for both rheumatoid and osteoarthritis sufferers.233 The FDA has approved over-the-counter capsaicin preparations for this use.
Antibiotics. The ancient Mayans used extracts of chilies as antibiotics. Modern research has begun to discover that the pepper does indeed have some antimicrobial properties.234 Exactly how those properties can be of use is still unknown.
Treating colds and flu. The Cherokee used it for colds.235 The 1918 U.S. Dispensatory recommended capsicum tincture for “sluggish conditions of the throat.” It also has been used traditionally to help sweat out a fever.236 Capsaicin irritates mucus membranes causing the nose to run. In that way, it can help with colds that clog the nose and sinuses, but it is unlikely to benefit colds where the primary symptom is already a runny nose. A study of a nasal spray containing capsaicin found that though it was quite painful, it did reduce nasal obstruction and nasal secretion in patients with vasomotor rhinitis (a chronic runny nose not caused by a virus or allergies) over the course of a month.237 Such a nasal spray would probably be ill advised for colds, however, because the treatment reached its full benefit over the course of a month, long after a typical cold would be over. Capsicum has been tried with some success against tonsillitis, but this study was not very large or well controlled, so it’s not sure what exactly the benefits might be.238
Increasing athletic performance. One study found that adding 10 g of red pepper to men’s diet increased the carbohydrate oxidation without increasing total energy expenditure for 150 minutes after the meal.239 In other words, it increased the ability of the body to burn carbohydrates for fuel without increasing the need for that fuel. A similar study found that 10 g of red pepper added to breakfast increased carbohydrate oxidation in male long distance runners both at rest and during exercise.240 A third study of Japanese women, on the other hand, found that adding red pepper to a meal actually decreased carbohydrate oxidation. Though theoretically increasing carbohydrate oxidation could make more fuel available for athletic performance, it is by no means certain that (1) A direct link exists between carbohydrate oxidation and improved performance, and (2) capsaicin does indeed increase carbohydrate oxidation in all athletes.
Slowing bleeding. One traditional use is to take a couple of capsules or drink a half-teaspoon of capsicum in a glass of water to slow bleeding. We have no scientific backing or cross-cultural attestation for this use.
How do you use it?
Commercial preparations. By far, the safest way to use capsaicin topically is to use it in a commercial preparation. It is really the only way to control the amount of capsaicin you are putting on your skin. Too little won’t give you the relief you seek; too much can damage your skin.
Infusions. Make an infusion using ½ teaspoon of dried peppers to one cup of boiling water. Stir and let the mixture sit for ten minutes. If you wish, you can strain it at this time, or you can use it without straining. Use 1 tablespoon of this infusion with a cup of water to make tea. The tea can be used to help unplug the nose during a cold. It can also be applied to a compress and used for sprains, bruising, and joint pain.241
Infused oil. Add 25 g of powder to two cups sunflower oil and heat in a double boiler for two hours. This infused oil is good as a massage oil for joint pain. Don’t use it with additional heat (such as a heating pad, hot water bottle or warm flannel), however, because this increases the chance of irritation and blistering. If you want to take a hot bath or shower, do so first, and then let the skin cool before applying capsaicin.242
Tincture. 95% alcohol 1:5 (pepper to alcohol)243 Dilute the tincture 1:10 to use as a liniment.244
A vinegar tincture can be made by boiling 1 tablespoon of pepper with 1 pint of cider vinegar. While the vinegar is still hot, pour it into a clean bottle without straining out the pepper.245
Muscle rubs: A muscle rub can be made by adding ¼ teaspoon powdered capsicum to 1 cup grain alcohol. Of course, you should use this rub topically only.246
Dosage: How much do you use?
The safety of chilis depends largely on how strong they are. The “heat” of the various peppers in the capsicum genus varies from nonexistent to extremely dangerous. The unit of measurement for chili “heat” is the Scoville unit. Pure capsaicin rates at 15,000,000 Scoville units; bell peppers rate at 0 Scoville units. Cayenne peppers of the species frutescens rate at 30,000–50,000 units.247 If you use stronger peppers, you must adjust the dose appropriately. It cannot be stressed enough: some varieties of peppers can cause blisters and burns bad enough to strip the skin right off you. Know what you have in your hand before trying to use it medicinally.
If you are buying your capsicum preparations over the counter, Commission E recommends liquid preparations not contain more than .01% pure capsaicin.
Topical preparations. Poultices and compresses should deliver no more than 40 g of capsaicinoids per square centimeter.248 Creams containing .025% and .075% capsaicin are available over the counter in both the United States and Canada. Stronger “back-alley” creams can be found, but are unadvisable. Don’t use topical preparations for longer than 2 days; 14 days must pass before a new application can be used in the same location.249