Use of cayenne pepper spans a variety of cuisines and its medical properties also make it a very useful source of vitamins and nutrients. Cayenne is high in vitamin A, vitamin B6, vitamin E, vitamin C, riboflavin, potassium, and manganese. This makes cayenne a great source for digestive health, joint and tissue maintenance, and heart health. It also has been proven to strengthen the immune system.
Two teaspoons of cayenne pepper contain about 11 calories. The medicinal part of this herb is the fresh or dried fruit. It should not be applied to open wounds or eyes. People who have gastrointestinal disorders as well as renal disease should avoid cayenne as it has a tendency to cause stomach inflammation. People who are taking ACE inhibitors, anticoahulants antiplatelet agents, thrombolytic agents, low molecular weight heparins, barbiturates, and theophyllines should use caution when taking or eating cayenne. It can be found in cream, capsule, and liquid extract form.
The fresh or dried fruits of different Capsicum species are used medicinally.
Flower and Fruit
The flowers are usually solitary, but may occasionally be in pairs or in threes. They are hanging and long-pedicled. The calyx is semiglobose to campanulate and has 5 to 7 tips. The corolla is wheel-shaped with a short tube, varying in color from white to yellow, occasionally from purple to violet with whitish-green or violet markings. There are 5 to 6 stamens with violet anthers and 5 small papillous staminoids. The ovary is superior. The dividing walls are partially underdeveloped. The seed carriers at the top are attached to the walls and fused to a column below. The berry is 1.5 to 5 cm long and up to 9 cm thick; it varies in form. The wall of the fruit is tough and leathery and may be red, yellow-green, or brownish. The seeds are numerous, light, yellowish-white, flat, circular or kidney-shaped and thickened at the margins. The surface is pitted.
Leaves, Stem, and Root
Capsicum annum is an annual (perennial in the tropics) 20 to 100 cm high plant with an erect stem, which is somewhat woody and angular. It is sparsely branched higher up. The leaves are usually solitary, long-petioled, oval, lanceolate to ovate, obtusely accuminate, wedge-shaped at the base, entire-margined or slightly curved and glabrous.
The herb is indigenous to Mexico and Central America and is cultivated today in warmer regions of the globe.
Paprika consists of the dried ripe fruit of Capsicum anuum or Capsicum fructescens. The fruit is harvested when completely ripe and dried at a maximum temperature of 35º C.
Not to be Confused With
Other varieties of Capsicum anuum.
African Pepper, Bird Pepper, Capsicum Chili Pepper, Chilies, Chili, Goat's Pod, Grains of Paradise, Hungarian Pepper, Red Pepper, Paprika, Sweet Pepper, Tabasco Pepper, Zanzibar Pepper
Actions & Pharmacology
Capsaicinoids (amides of the vanillyl amine with C8 - C13-fatty acids): chief components capsaicin (32-38%), dihydrocapsaicin (18-52%)
Carotinoids (0.3-0.8%): in particular capsanthin (dark red), alpha-carotin, violaxanthine, free or as fatty acid esters
Flavonoids: including apiin, luteolin-7-O-glucoside
Steroid saponins: mixture referred to as capsicidine, in the seeds
Volatile oil (0.1%): 2-methoxy-3-isobutyl pyrazine and N-(13-methyl tetradecyl)acetamide (capsiamide)
Capsaicin relieves pain by depleting neuropeptides which initiate pain perception (Appendino & Szallasi, 1997; Fusco & Giacovazzo, 1997). Conflicting evidence exists concerning the role of capsaicin as a chemopreventive agent or a cancer-inducing agent (Surh & Lee, 1996; Surh & Lee, 1995). Similarly confusing are reports of gastroprotective (Kang et al, 1996) versus gastric-damaging effects (Myers et al, 1987). Capsaicin also demonstrates antimicrobial activity in vitro (Jones et al, 1997).
Efficacy of the drug has to date not been demonstrated for the claimed indications, especially internal applications, using the valid criteria for the clinical testing of drug substances. The significant tendency toward hyperemia caused by the content of irritant constituents in the drug does, however, provide antinoceptive and antiphlogistic effects with external administration, which could be used in the treatment of rheumatic illnesses, neuralgia, and myalgia.
The most important active ingredient in the herb is the capsaicin, which exerts hyperemic effects. Cutaneous nociceptors are also known as peripheral sensory neurons of primary sensory neurons activated by noxious stimuli (Biro, 1997; Nakamura, 1999). Peripheral fibers produce a local response consisting of edema, redness, and vasodilation while afferent fibers relay nociceptive information to the central nervous system resulting in the perception of pain and burning. Long-term desensitization of the fibers occurs after repeated exposure to capsaicin, and results in a subsequent loss of pain sensation (Appendino, 1997; Fusco & Giacovazzo, 1997).
Capsaicin binds to the C-type vanilloid receptor (VR1) and opens a cationic channel allowing the influx of calcium. The calcium influx is an excitatory response, which initiates release of neuropeptides (substance P). The neuropeptides are responsible for chemogenic pain, thermoregulation and neurogenic inflammation. By blocking the calcium channel, there will be a depletion of substance P in the sensory nerves and loss of pain (Appendino, 1997; Biro, 1997; Fusco & Giacovazzo, 1997; Jung, 1999).
The pain relief observed with topical capsaicin is unlike anesthetics in that pain is blocked without effects on other sensations, such as touch and vibration (Bernstein et al, 1989; Fitzgerald, 1983).
The degeneration of epidermal nerve fibers contributes to the analgesia accredited to capsaicin. Discontinuation of capsaicin has resulted in reinnervation of the epidermis over a 6-week period in one trial (Nolano et al, 1999).
Various extracts of Cayenne as well as isolated capsaicin have shown inhibitory potential in vitro against Bacillus cereus, Bacillus subtilis, Clostridium sporogenes, Clostridium tetani, and Streptococcus pyogenes (Cichewicz, 1996). Capsaicin has shown bactericidal activity against Helicobacter pylori and therefore could have a protective effect against H pylori-associated gastroduodenal disease (Jones, 1997). It did not inhibit growth or kill nonpathogenic Escherichia coli.
A study using capsaicin from jalapeno peppers did not support the role for jalapenos in the treatment of H pylori infection (Graham, 1999).
Capsaicin, once thought to be carcinogenic, has been shown not to cause any significant increase in papilloma formation, abnormal hyperplasia, or inflammatory lesions. The drug does not induce the epidermal ornithine decarboxylase activity, suggesting that it lacks tumor-promotional activity (Park, 1997; Park, 1998). Chemoprotective effects of capsaicin and dihydrocapsaicin include the inhibition of microsomal monooxygenases involved in carcinogen activation (Surh, 1995).
Inhibition of the enzyme CYP2E1 may prevent activation of small molecular weight chemical carcinogens such as dimethylnitrosamine. Additionally, capsaicin may have a protective effect on metabolism, DNA binding, and mutagenicity of selected chemical carcinogens, including aflatoxin and tobacco-specific nitrosamine. These data suggest a chemoprotective effect of capsaicin (Surh & Lee, 1996; Surh & Lee, 1995).
In a case-control study conducted in Mexico City, a significant correlation was found between consumption of hot pepper and gastric cancer (Lopez-Carrillo et al, 1994).
Capsaicin and dihydrocapsaicin have detoxification activity with pharmacologically active substances by interacting irreversibly with hepatic drug-metabolizing enzymes (Surh, 1995). Capsaicin has a gastroprotective effect against gastric mucosal injury caused by aspirin (Yeoh, 1995). Capsicum has been found to induce increased fibrinolytic activity and simultaneously cause hypocoagulability of blood (Visudhiphan, 1982).
A Chochrane Collaboration Review of herbal medicines for nonspecific low back pain cited a study involving Cayenne in plaster form, which in the study was found to reduce pain more than placebo did—and approximately the same amount as a homeopathic gel called Spiroflor SLR. The adverse effects reported were primarily mild and transient, and gastrointestinal in nature. However, the review failed to provide convincing data to substantiate the safety and effectiveness of Cayenne and other herbal medicines for long-term use as analgesics (Gagnier, 2007).
In an earlier double-blind, placebo-controlled study, capsaicin cream reduced neuropathic pain in patients with diabetes mellitus. All patients (n=277) had moderate-to-severe pain due to peripheral neuropathy or radiculopathy. Throughout the study, the placebo response was high, up to 58.1% on the physician global evaluation scale and 45.4% on the VAS pain relief scale used by patients. Based on this study, capsaicin cream is effective in some patients with diabetic neuropathy but burning is a frequent side effect which may lead to treatment discontinuation (Anon, 1991).
The efficacy of topical capsaicin was determined in 22 patients with chronic, severe painful diabetic neuropathy over an 8-week study period in a randomized, placebo-controlled study. Significant improvement was seen with capsaicin 0.75% applied 4 times daily for the overall clinical improvement of pain status, as measured by physician's global evaluation and by a categorical pain severity scale. The capsaicin treatment group had a 44.6% decrease in mean pain relief on VAS versus 23.2% decrease with the placebo group. Approximately 50% of subjects reported improved pain control or were cured in a follow-up, open-label study, and 25% were unchanged or worse (Tandan, 1992).
In a small study (n=21), capsaicin cream improved tenderness and pain in joints with osteoarthritis (OA) but had no beneficial effect in patients with rheumatoid arthritis (RA). All patients had arthritic pain in the small joints of the hands. Treatment was randomly allocated and blinded; it consisted of application of vehicle or capsaicin cream 0.075% 4 times daily for 4 weeks. Tenderness and pain scores were reduced significantly at 4 weeks in patients with OA (n=14); however, other parameters including swelling, grip strength, duration of morning stiffness, subjective pain, and function were not improved. Patients with RA (n=5, completed study) had no response to capsaicin cream. This study suffered from several deficiencies including a small sample size and potential loss of blinding due to burning after capsaicin application (McCarthy & McCarty, 1992).
Patients with osteoarthritis (OA) (n=70) and rheumatoid arthritis (RA) (n=31) had a reduction in knee pain during treatment with capsaicin cream. Capsaicin appears useful as an adjunct to standard therapy to increase pain relief at a limited number of joints with intense pain (Deal et al, 1991).
Ten adult patients with chilblains, also known as perniosis, had complete healing of all lesions after 10 days of treatment with capsaicin. All patients were in the edematous, erythematous phase of chilblains. Few therapies have been effective for treating chilblains; therefore, capsaicin, if effective in larger, controlled studies, would be a useful new therapy for this condition. The mechanism by which capsaicin has beneficial effects is unknown but may be due to effects of a vasoactive neuropeptide in regulating blood flow and fibrinolytic activity in the skin (Cappugi et al, 1995).
Cough Sensitivity Test
Children with recurrent cough showed a heightened response to the capsaicin cough sensitivity test compared with children with asthma, cystic fibrosis, or normal airways. After controlling for age, sex, and spirometry, the dose at which capsaicin induced cough was significantly lower than in the other groups (Chang et al, 1997a).
In a randomized, crossover, intervention study, the metabolic effects of a chili meal containing cayenne after the consumption of a bland diet and a diet supplemented with a chili-blend (30 g/day; 55% cayenne chili) was investigated. Thirty-six subjects participated in the trial with 2 dietary periods (chili and bland) of 4 weeks. The postprandial effects of a bland meal after a bland diet, a chili meal after a bland diet, and a chili meal after a chili-containing diet were evaluated. Serum insulin, C-peptide, and glucose concentrations and energy expenditure were measured at fasting and up to 120 min postprandially. Results showed that regular consumption of chili containing cayenne may attenuate postprandial hyperinsulinemia (Ahuja et al, 2006). The same authors also studied the effect of 4-week chili supplementation on metabolic and arterial function, but did not find obvious beneficial or harmful effects on metabolic parameters. However, their findings suggest that cayenne may reduce resting heart rate and increase effective myocardial perfusion pressure time in men (Ahuja et al, 2007).
The efficacy of capsaicin as a gastroprotective agent was determined in 18 healthy volunteers with normal index endoscopies. The volunteers underwent two studies 4 weeks apart to evaluate the effect of capsaicin against aspirin-induced gastric mucosal injury. The median gastric injury score in the chili group was significantly less than that of the aspirin group, demonstrating a gastroprotective effect of chili in human subjects (Yeoh, 1995). In a crossover study of 18 healthy subjects, treatment with capsaicin prior to aspirin administration significantly decreased gastric mucosal damage as compared with aspirin alone (Yeoh et al, 1995).
Nausea and Vomiting, Postoperative
In a double-blind, placebo-controlled study, postoperative nausea and vomiting occurred with lower frequency in women undergoing abdominal hysterectomy who were treated with a capsaicin-containing plaster than in those treated with an unmedicated plaster (Kim et al, 2002).
Excellent or satisfactory improvement in urinary incontinence occurred in about 80% of patients treated with intravesical capsaicin. Patients with spinal cord disease primarily due to multiple sclerosis and those who had a failure to adequately respond to other therapy received capsaicin after a filling cystometrogram. Results of this and other studies indicate that patients with residual lower-limb function and strong motivation to overcome incontinence receive the greatest benefit from intravesical capsaicin (de Ridder et al, 1997).
In a double-blind study, Capsaicin cream 0.075% applied 4 times per day gave pain relief to elderly patients suffering from chronic postherpetic neuralgia. Clinical improvement was reported in 77% receiving capsaicin and in 31% receiving placebo. More patients (54%) in the capsaicin group experienced 40% or greater pain relief than in the placebo group (6%). Burning, stinging, and erythema were reported in 5 patients treated with capsaicin and in 2 receiving placebo. These local effects usually subsided with continued application (Bernstein et al, 1989).
In a study, 19 of 22 patients with hemodialysis-related pruritus had relief of pruritus following treatment with capsaicin for 4 weeks (Cho et al, 1997).
Topical capsaicin reduced the pain of post-surgery neuropathy in a majority of subjects in a double-blind, placebo-controlled crossover trial. There was a tendency for pain relief to be greater with post-mastectomy pain than with pain from other sources (amputation, thoracotomy). Patients who received capsaicin in the first 8 weeks maintained their level of pain relief during the placebo period (Ellison et al, 1997).
Indications & Usage
Approved by Commission E:
- Muscular tensions
Cayenne is used for painful muscle spasms in areas of shoulder, arm, and spine. In folk medicine the herb is used for frostbite, chronic lumbago, and as a gargle for hoarseness, sore throats, and infected throats. The drug is also used internally for gastrointestinal disorders, seasickness, and as prophylactic therapy for arteriosclerosis, stroke, and heart disease.
The herb is used in cream form for circulation and as a female orgasm stimulant. Use should be limited to 2 days, and should only be used again after 2 weeks. Longer usage can cause festering dermatitis, blistering, and ulceration (See PRECAUTIONS).
Cayenne is used for gout, arthritis, sciatica, coughs, and hoarseness. It has been used for lowering the temperature in malaria, yellow fever, scarlet fever, and typhus. It is used for cholera, edema, and anorexia nervosa. It is used in compound preparations for loss of appetite, dyspepsia, and diarrhea (tablets 1:1:1; Cayenne pepper, rhubarb and ginger root) and for alcoholism as an infusion (Cayenne pepper with sugar and cinnamon) to reduce the desire for alcohol.
The herb is used for inflammation of the efferent urinary tract, the alimentary canal, the mouth and throat, and middle ear infection.
Capsaicin cream should not be applied to open wounds or to the eyes. Other contraindications include stomach ulcers or stomach inflammation, chronic irritable bowel, and inhalation. Avoid use in patients with gastrointestinal and renal disease (Palevitch & Craker, 1993).
Precautions & Adverse Reactions
Burning, stinging, and redness of skin are all possible side effects of Cayenne use. This is a normal action of capsaicin and these effects almost always lessen and disappear over a few days time with repeated application. Accidental transfer of the cream to the eyes or mucous membranes can cause temporary burning. If worsening occurs or no improvement occurs after 7 days, stop using the product. Wash hands immediately after use unless treating the hands.
There has not yet been a final determination of possible health hazards or side effects in conjunction with the proper administration of designated therapeutic dosages. Internal administration may increase gastrointestinal peristalsis resulting in diarrhea, intestinal, and gallstone colics. Besides the intended stimulating effect, external applications can lead to blister and ulcer formation. Investigations into mutagenicity, teratogenicity, and carcinogenicity yielded contradictory results.
Warning: Use should be limited to 2 days and should only be used again after 2 weeks. Keep away from the eyes!
High intake of cayenne peppers as food has been correlated to an increased risk of gastric carcinoma in one case-control study of 972 persons in Mexico (Lopez-Carrillo et al, 1994). Any consumption of chilies was correlated with an odds ratio of 5.49 for risk of stomach cancer and 17.11 for those who self-rated in the highest tertile of intake. The dose-response curve was inexplicably flat in this study. A related review of the literature summarizes available data by stating that low doses of cayenne may be anticarcinogenic while higher doses may be carcinogenic (Surh & Lee, 1996).
Central Nervous System Effects
Topical capsaicin in concentrations of 1% or greater has been associated with neurotoxicity and thermal hyperalgesia (Reynolds, 1991; Robertson & George, 1990).
Local discomfort characterized by burning, stinging, and redness of the skin occurs frequently after application of topical capsaicin; local discomfort is increased when capsaicin cream is applied fewer than 3 to 4 times daily. Local reactions usually subside within 72 hours of beginning regularly scheduled use of topical capsaicin (Bernstein et al, 1989; Bernstein et al, 1987).
Capsicum has been found to induce increased fibrinolytic activity and simultaneously cause hypocoagulability of blood (Visudhiphan, 1982).
Anaphylaxis and rhinoconjunctivitis symptoms have been associated with the herb due to its antigenic components (Jensen-Jarolim, 1998; Vega de la Osada, 1998). Contact dermatitis has been reported from the direct handling of chili peppers containing capsaicin (Williams, 1995). A hypersensitivity reaction known as plasma cell gingivitis may occur with the herb, and may cause severe gingival inflammation, discomfort, and bleeding (Serio, 1991). One study suggests the allergy is rarely an autonomous sensitization, but rather a consequence of pollen allergy on the basis of immunologic cross-reactivity (Ebner, 1998).
Three experiments were conducted in healthy young women (n=10 per study) to evaluate the effect of chili pepper and turmeric on iron absorption, and to identify a possible effect of chili on gastric function. Freeze-dried, ground chili pepper within the range of habitual chili intake by Thai adults (14.2 g fresh wt; 25 mg polyphenols as gallic acid equivalents) reduced iron absorption from a basic meal of vegetables and rice by 38%, but the authors note that the findings don't necessarily show that chili intake is a risk factor for iron depletion. (Turmeric, in contrast, did not inhibit iron absorption.) The authors conclude that both the quality and quantity of the phenol compounds in plants determine their iron-absorptive inhibitory powers (Tuntipopipat, 2006).
Chronic exposure to chili peppers has been associated with an increase in cough (Blanc, 1991). Capsaicin inhalation has been associated with cough and a transient increase in airway resistance. These effects are likely related to stimulation of sensory airway nerves (Fuller, 1991). Cough induced by inhaled capsaicin has been exacerbated by pretreatment with angiotensin converting enzyme (ACE) inhibitors (O'Hollaren & Porter, 1990).
Angiotensin converting enzyme (ACE) inhibitors
May result in increased risk of cough when used concurrently with topical capsaicin. Clinical management: Patients should be advised to discontinue capsaicin use if they experience cough while taking capsaicin and an ACE inhibitor. Since the incidence of this effect is not yet known and it is presently not possible to predict which patients will experience this adverse effect, complete avoidance of the combination is not recommended at this time.
Anticoagulants, antiplatelet agents, thrombolytic agents, and low molecular weight heparins
Concurrent use of capsaicin with these medications may increase the risk of bleeding. The clinical significance of capsaicin's effect on platelet aggregation and fibrinolytic activity is unknown. Clinical Management: Signs and symptoms of excessive bleeding should be monitored closely if capsaicin and any of these agents are taken concomitantly. It is advisable to discontinue appreciable intake of capsaicin (or large amounts of red pepper) prior to administration of anticoagulants, antiplatelet agents, low molecular weight heparins, or thrombolytic agents.
Concurrent use may result in increased or decreased effect of the barbiturate, depending on the length of time capsaicin is administered. Clinical Management: Until the clinical significance of this interaction is better studied in humans, patients prescribed barbiturates are advised to avoid concomitant use of capsaicin.
Concomitant use of capsaicin and theophylline may result in an increased risk of theophylline toxicity and should be undertaken with caution. Clinical Management: Theophylline levels and signs and symptoms of theophylline toxicity should be monitored closely if these agents are administered concomitantly.
Aspirin and salicylic acid compounds
The bioavailability of aspirin (acetylsalicylic acid) and of salicylic acid was reduced when given concomitantly with Capsicum annuum extract containing 100 mg of capsaicin per gram as a result of the gastrointestinal effects of capsaicin (Cruz, 1999).
Toxic dosages lead to life-threatening hypothermia by affecting the thermoreceptors. High doses of the drug (or the herb) administered over extended periods can cause chronic gastritis, kidney damage, liver damage, and neurotoxic effects. The treatment for poisonings proceeds symptomatically.
Mode of Administration
Preparations of Cayenne are exclusively for external indications in antirheumatic ointments and plasters.
- Capsules–400 mg, 445 mg, 450 mg, 455 mg, 500 mg
- Cream–0.25% capsaicin, 0.75% capsaicin
- Liquid Extract
A liquid extract is prepared by percolating 100 g drug with 60 g ethanol. Other formulations include: Capsicum-oleoresin with 90% ethanol and a tincture with 90% ethanol.
External daily dose: 10 g drug; Tincture: (1:10); Semisolid preparations: maximum 50 mg capsaicin in 100 g neutral base. The cream is applied to the affected area not more than 3 or 4 times daily (Zostrix Package Insert, 1998).
Internal application: Decoction: 1/2liter water with 5 g powdered drug, 3 g powdered cascarilla bark and 5 g powdered rhubarb root; 2 cups per day.
5 drops, 1 tablet, or 10 globules every 30 to 60 minutes (acute) or 1 to 3 times a day (chronic); ointment: once or twice daily (HAB1)
Should be well sealed and protected from light.