

Capsicum, red pepper, hot pepper, African chillies, conoids, Tabasco pepper, paprika, pimiento, mexican chilies, longum, Louisiana long pepper
Derived from the fruit of Capsicum, cayenne is among the most widely consumed culinary spice. Traditionally, it is used topically as a rubefacient, as a gargle for laryngitis and orally as a gastrointestinal stimulant. The active component, capsaicin, is an irritant which has been used in scientific studies to evaluate pain sensation.
Phytochemical extracts of capsicum have been shown to exhibit more antioxidant activity than broccoli, carrot or spinach (3). Topical capsaicin cream may be effective against chronic soft tissue pain (22) and low back pain (13). Capsaicin may also increase insulin and decrease blood glucose levels (14). Supplementation with capsicum for burning mouth syndrome is associated with significant side effects (4).
In vitro studies have shown that capsaicin has cytotoxic effects against multidrug resistant lymphoma (5), oral tumor cell lines (6) and inhibits leukemia cell growth (7). Topical capsaicin may alleviate oral mucositis pain associated with chemotherapy and radiation therapy (8). Capsaicin cream has also been shown effective in reducing post-surgical pain in cancer patients (9) and for treating psoriasis (10) (11) and pruritus (12).
Use of gloves is recommended when applying topical capsaicin. An adverse effect of topical administration is burning following contact with moist mucous membranes (1) (2).
Toxicities following overdoses from oral injestion include gastroenteritis and renal damage (15). There are reports of erythematous dermatitis formed in infants subsequent to breast-feeding from mothers who had ingested food flavored with red pepper (16). Administration of even a single dose of capsicum may interfere with theophylline metabolism (17).
Fruits of capsicum pepper.
The phenolic compound capsaicin is responsible for the irritant effects of capsicum (1). Studies show that 100g of the pepper has equivalent antioxidant activity of 826 mg of vitamin C (3). Lignan glycosides isolated from the capsicum pepper were also shown to be potent antioxidants as demonstrated by a strong scavenging activity against the free radical, DPPH (19). The pain relieving property of capsaicin is thought to be due to its ability to desensitize neurons when applied to the skin surface (8).
The active components in capsicum also have anticancer activities (20).
Absorption:
The active component capsaicin is absorbed through the skin, mucus membrane and in the G.I. tract. Capsaicin produces motor effects on gut motility that may affect the absorption of itself or other drugs. Capsaicin may affect the ability to absorb drugs via an alternate pathway than Cytochrome P450 (17).
Chalyasit K, et al. Pharmacokinetic and the effect of capsaicin in Capsaicum frutescens on decreasing plasma glucose level. J Med Assoc Thai. 2009 Jan;92(1):108-13.
A placebo-controlled, crossover study was conducted to determine the effect of capsaicin on plasma insulin and blood glucose levels. This study enrolled 12 healthy volunteers who received a single dose of either placebo or 5 grams of capsicum. After a 1 week washout period, the subjects were then crossed over to receive the other treatment. Insulin secretion and capsaicin levels in plasma were measuring using an HPLC method. The results of an oral glucose tolerance test demonstrated that plasma glucose levels in the subjects who had received capsicum were significantly lower than those in the placebo group at 30 and 45 minutes (p<0.05). Plasma insulin levels of subjects receiving capsicum were also significantly higher at 60, 75, 105, and 120 minutes (p<0.05) than those receiving placebo. The study also found that capsaicin levels achieved after the ingestion of 5 grams of capsicum were associated with a decrease in plasma glucose levels. The authors concluded that these study results may have clinical implications for the management of type 2 diabetes.
Bottom Line: Oral and topical cayenne may help in alleviating some of the side effects of chemotherapy and radiation therapy such as mucositis pain and neuropathy.
The capsicum pepper contains a chemical called capsaicin that is a powerful irritant. It is thought that this chemical can sensitize nerves that report painful stimuli to the brain. Laboratory tests of capsaicin show that it may be able to kill cancer cells, however, a comparable effect in humans has not been shown. The capsicum pepper has also been shown to display powerful antioxidant activities.
Oral mucositis:
Oral capsaicin was administered via capsaicin-laced taffy to eleven patients with oral mucositis pain from cancer therapy. Limited, temporary relief was provided by the therapy. Further study is warranted.