Also Known As:

African Bird Pepper, African Chillies, African Pepper, Aji, Bird Pepper, Capsaicin, Capsaïcine, Cayenne, Cayenne Pepper, Chili, Chili Pepper, Chilli, Chillies, Cis-capsaicin, Civamide, Garden Pepper, Goat's Pod, Grains of Paradise, Green Chili Pepper, Green Pepper, Hot Pepper, Hungarian Pepper, Ici Fructus, Katuvira, Lal Mirchi, Louisiana Long Pepper, Louisiana Sport Pepper, Mexican Chilies, Mirchi, Oleoresin Capsicum, Paprika, Paprika de Hongrie, Pili-pili, Piment de Cayenne, Piment Enragé, Piment Fort, Piment-oiseau, Pimento, Poivre de Cayenne, Poivre de Zanzibar, Poivre Rouge, Red Pepper, Sweet Pepper, Tabasco Pepper, Trans-capsaicin, Zanzibar Pepper, Zucapsaicin, Zucapsaïcine.

CAUTION: See separate listings for Grains of Paradise and Indian Long Pepper.

Scientific Name:

Capsicum frutescens; Capsicum annuum; Capsicum chinense; Capsicum baccatum; Capsicum pubescens; Capsicum minimum; and other Capsicum species.
Family: Solanaceae.

People Use This For:

Orally, capsicum is used for dyspepsia, flatulence, colic, diarrhea, cramps, toothache, poor circulation, excessive blood clotting, seasickness, swallowing dysfunction, alcoholism, malaria, fever, hyperlipidemia, and preventing heart disease.
Topically, capsicum is used for the pain of shingles, osteoarthritis, rheumatoid arthritis, post-herpetic neuralgia, trigeminal neuralgia, diabetic neuropathy, back pain, and post-surgical neuralgias. It is also used topically for prurigo nodularis, HIV-associated neuropathy, and fibromyalgia. Capsicum is also used to relieve muscle spasms, as a gargle for laryngitis, and as a deterrent to thumb-sucking or nail biting.

Intranasally, capsicum is used for allergic rhinitis, perennial rhinitis, migraine headache, cluster headache, sinonasal polyposis, and sinusitis

Safety:

LIKELY SAFE ...when used orally in amounts typically found in food. Capsicum has Generally Recognized As Safe (GRAS) status in the US (5). ...when used topically and appropriately. The active capsicum constituent capsaicin used in topical preparations is an FDA-approved over-the-counter product (1).
POSSIBLY SAFE ...when used orally and appropriately, short-term in medicinal amounts (16,17). ...when used topically and appropriately (11,12). ...when used intranasally and appropriately, short-term. Capsicum-containing nasal sprays, suspensions, and swabs seem to be safe when applied daily or every other day for up to 14 days (28,30,31 ,32, 33, 34, 35, 38, 39, 40, 41, 42, 43). No serious side effects have been reported in clinical trials, however, application of capsicum-containing products intranasally can be very painful.
POSSIBLY UNSAFE ...when used orally, long-term or in high doses. There is concern that long-term use or use of excessive doses might be linked to hepatic or renal damage (16). (
CHILDREN: POSSIBLY UNSAFE ...when used topically in children under 2 years old (1). There is insufficient reliable information available about the safety of capsicum when used orally in children.
PREGNANCY: LIKELY SAFE ...when used topically and appropriately (1). There is insufficient reliable information available about the safety of capsicum during pregnancy when used orally in medicinal amounts.
LACTATION: LIKELY SAFE ...when used topically and appropriately (1). POSSIBLY UNSAFE ...when used orally. Dermatitis can sometimes occur in breast-fed infants when mothers ingest foods heavily spiced with capsicum peppers (2).

Effectiveness:

LIKELY EFFECTIVE

Pain. Several clinical studies show that applying 0.25% to 0.75% capsaicin cream topically temporarily relieves chronic pain from rheumatoid arthritis, osteoarthritis, psoriasis, and neuralgias including shingles and diabetic neuropathy (13, 47). The active capsicum constituent capsaicin, used in topical preparations, is FDA-approved for these uses (1).
For neuropathic pain, the number needed to treat using capsaicin 0.075% for eight weeks is 5.7 (13).  (12401).
For musculoskeletal pain, for every 8.1 patients treated with 0.025% capsaicin, one would achieve at least a 50% reduction in pain (13). In a study using 0.05% capsaicin (Finalgon CPD Warmecreme) applied three times daily for 21 days, there was a 49% reduction in pain compared to placebo in patients with chronic soft tissue pain (47).

POSSIBLY EFFECTIVE

Back pain. Some evidence shows that applying a capsicum-containing plaster to back can significantly reduce low-back pain compared to placebo (44, 45. 46).
Cluster headache. Some evidence shows that using capsaicin intranasally might reduce the frequency of episodic or chronic cluster headache attacks (29, 33, 34, 40). Intranasal application of capsaicin 0.025% (Zostrix, Rodlen Laboratories) might also decrease symptom severity during an acute cluster headache attack. Daily treatment for 7 days seems to decrease symptom severity over the following week (35). Ipsilateral, or same side, nostril application of capsaicin appears to be more effective than contralateral application (33).
Fibromyalgia. Applying cream containing 0.025% of the active capsicum constituent capsaicin 4 times daily to tender points for 4 weeks seems to reduce tenderness in patients with fibromyalgia (11).
Perennial rhinitis. Some evidence suggests that intranasal treatment with capsaicin solution can significantly decrease symptoms of non-allergic, non-infectious perennial rhinitis symptoms ( 34, 39, 43) A decrease of symptoms has been observed for 6-9 months following intranasal capsaicin treatment (34, 39) 

Prurigo nodularis. Applying a cream containing 0.025% to 0.3% of the active capsicum constituent capsaicin 4-6 times daily seems to relieve burning sensations, erythema, pruritus, and healing of skin lesions over a period of 2 weeks to 33 months. Symptoms, however, may return after discontinuation of therapy (48).

POSSIBLY INEFFECTIVE

HIV-associated peripheral neuropathy. Applying capsaicin topically does not seem to relieve symptoms of HIV-associated peripheral neuropathy (4).

INSUFFICIENT RELIABLE EVIDENCE to RATE

Allergic rhinitis. Preliminary research suggests that intranasal treatment with cotton wads soaked in capsaicin applied for 15 minutes and repeated over two days might reduce the severity of experimentally induced allergic rhinitis. Severity of symptoms seems to be decreased for up to two months after capsaicin treatment (30). However, contradictory evidence suggests that patients with allergic rhinitis caused by house dust mites do not have significantly improved symptoms after using a capsaicin solution providing 0.15 mg/dose for up to 7 doses over a 14-day period (42).
Dyspepsia. Preliminary evidence suggests that red pepper powder in capsules taken before meals 3 times daily reduces symptoms of functional dyspepsia. In some patients, there seems to be a worsening of symptoms before improvement (22). (12410).
Irritable bowel syndrome (IBS). Preliminary evidence suggests that capsicum fruit taken orally doesn't help symptoms of IBS (15).
Migraine headache. Anecdotal evidence suggests that intranasal application of capsaicin 0.075% might help abort a migraine headache (35).
Peptic ulcers. There is preliminary evidence that suggests people who eat capsicum fruit (chili) an average of 24 times per month appear to be less likely to have an ulcer than people who eat chili an average of 8 times per month. This applies to chili in the form of chili powder, chili sauce, curry powder, and other chili-containing foods (12).  
Sinonasal polyposis. Preliminary evidence suggests that intranasal application of capsaicin can cause significant subjective improvement in symptoms as well as objective improvement in nose/sinus air volume and endoscopy scores in patients with severe sinonasal polyposis; however, capsaicin does not seem to significantly affect eosinophil cationic protein levels (41). 

Swallowing dysfunction. Preliminary evidence suggests that elderly patients at risk for aspiration pneumonia due to swallowing dysfunction have improved swallowing reflexes after dissolving a capsaicin-containing lozenge in their mouth before each meal (27).
More evidence is needed to rate capsicum for these uses.

Mechanism of Action:

The applicable part of capsicum is the fruit. Capsicum contains the constituent capsaicin, which makes it taste hot.
Naturally-occurring capsaicin exists only in the trans-stereoisomer form. However, the cis-isomer, known as civamide, also has pharmacological activity. Some evidence suggests that civamide is more potent and causes less irritation than naturally occurring capsaicin. (29).
When used topically, capsaicin binds to nociceptors in the skin, initially causing neuronal excitation and heightened sensitivity. This is felt as itching, pricking, or burning. Capsaicin also causes cutaneous vasodilation. The mechanism for these effects is thought to be the result of selective stimulation of afferent C fibers, which act as thermoreceptors and nociceptors, and release of substance P, a sensory neurotransmitter that mediates pain. This is followed by a refractory period with reduced sensitivity. After repeated applications, persistent desensitization occurs, possibly the result of substance P depletion. Pain relief may also be caused by degeneration of epidermal nerve fibers (13, 16, 22).
Capsaicin also stimulates the unmyelinated slow C-fibers of the sensory nervous system, which can induce cough, dyspnea, nasal congestion, and eye irritation after inhalation (6).
Some research with inhaled capsaicin suggests that severity of ACE inhibitor cough correlates with sensitivity to inhaled capsaicin (23, 24, 25,26).
In people with swallowing dysfunction, capsaicin is thought to provide sensory stimulation that increases the swallowing reflex (27).
For allergic and perennial rhinitis, it is not clear how capsaicin nasal spray might work. Like for pain syndromes, capsaicin likely depletes substance P, resulting in desensitization of the nasal mucosa to antigens (30, 36). Some research suggests that capsaicin does not cause significant changes in nasal neuronal tissue. Capsaicin is thought to possibly have anti-inflammatory effects. But some research suggests that capsaicin does not affect inflammatory cell density in the nasal mucosa (28, 30). Or concentrations of inflammatory mediators such as leukotrienes or prostaglandins (34).  Other research in animal models of nasal hypersensitivity suggests that intranasal capsaicin decreases substance P and tyrosine hydroxylase-like immunoreactive nerve fibers (37).
For migraine and other headaches, capsaicin is thought to cause a desensitizing effect by relieving both peripheral and central pain by decreasing release of neuropeptides, such as substance P, from nerve terminals. When applied intranasally, capsaicin is also thought to decrease intranasal and central blood vessel neurotransmitters, cause vasodilation, and histamine or serotonin release (29). In animal models, intranasal capsaicin also seems to deplete nerve fibers that are immunoreactive to the neuropeptides substance P or calcitonin gene-related peptide (CGRP) (34).
Some researchers theorize that the capsaicin constituent might also have gastroprotective effects. Preliminary evidence suggests that capsicum protects against alcohol and non-steroidal anti-inflammatory drug (NSAID) damage to the GI mucosa. This has also led to the hypothesis that capsaicin might decrease the risk of peptic ulcer disease (12). However, with heavy ingestion, capsaicin has been associated with necrosis, ulceration, and carcinogenesis (16).
Capsaicin seems to have antiplatelet effects (18, 19). Some evidence shows capsicum extract has antibacterial properties (14).
Capsaicin is thought to be metabolized by the cytochrome P450 (CYP450) system to active metabolites. Whether these substances can cause cancer or protect against cancer by altering carcinogen metabolism is an area of active research (14). 

Capsicum powder has been reported to prevent radiation-induced damage to bacterial DNA and thereby protect certain bacteria (Escherichia coli, Bacillus megaterium, and Bacillus pumilus spores) from gamma irradiation, which is used to preserve some foods (6).

Adverse Reactions:

Orally, capsicum can cause upper abdominal discomfort including fullness, gas, bloating, nausea, epigastric pain and burning, diarrhea, and belching (12, 22). Sweating and flushing of the head and neck, lacrimation, headache, faintness, and rhinorrhea have also been reported (8, 22). Excessive amounts of capsaicin can lead to gastroenteritis and hepatic necrosis (13). There are also reports of dermatitis in breast-fed infants whose mothers' food is heavily spiced with capsicum (2). Capsicum can also decrease blood coagulation (9).
Topically, capsicum can cause burning, stinging, and erythema. About one in 10 patients who use capsaicin topically discontinue treatment because of adverse effects. Side effects tend to diminish with continued use (10). Exacerbation of ACE-inhibitor cough has been reported in patients using topical capsaicin and taking ACE-inhibitors (26). Skin contact with fresh capsicum fruit can cause irritation or contact dermatitis (20)
Intranasally, capsaicin can cause nasal burning and pain in most patients. It also often causes lacrimation, sneezing, and excessive nasal secretion (29, 35, 40): however, these side effects appear to diminish with repeat applications. In some cases, the burning sensation disappears after 5-8 applications (33, 40). In some cases, patients are pretreated with intranasal lidocaine to decrease the pain of intranasal capsaicin treatment. However, even with lidocaine pretreatment, patients seem to experience significant pain (30).
Inhalation of capsicum can cause cough, dyspnea, nasal congestion, eye irritation, and allergic alveolitis (6).
Capsicum can be extremely irritating to the eyes and mucous membranes. 

Capsicum oleoresin, an oily extract in pepper self-defense sprays, causes intense eye pain. It can also cause erythema, blepharospasm, tearing, shortness of breath, and blurred vision. In rare cases, corneal abrasions have occurred (20, 21).

Interactions with Herbs & Supplements:

ANTICOAGULANT/ANTIPLATELET HERBS AND SUPPLEMENTS: Concomitant use of herbs and supplements that affect platelet aggregation could theoretically increase the risk of bleeding in some people. Some of these herbs include angelica, clove, danshen, garlic, ginger, ginkgo, Panax ginseng, and others.
COCA: Theoretically, concomitant use of capsicum (including exposure to the capsicum in pepper spray) and coca might increase the effects and risk of adverse effects of the cocaine in coca (3).

Interactions with Drugs:

ACE INHIBITORS (ACEIs) <<interacts with>> CAPSICUM

Interaction Rating = Minor Be watchful with this combination.

Severity = Mild • Occurrence = Unlikely • Level of Evidence = D

There is one case report of a topically applied cream containing capsaicin contributing to the cough reflex in a patient using an ACE-inhibitor (26). (12414). But it is unclear if this interaction is clinically significant.

ANTICOAGULANT/ANTIPLATELET DRUGS <<interacts with>> CAPSICUM

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = D

Theoretically, capsicum might increase the effects and adverse effects of antiplatelet drugs (15, 16). 

COCAINE <<interacts with>> CAPSICUM

Interaction Rating = Moderate Be cautious with this combination.

Severity = High • Occurrence = Possible • Level of Evidence = D

Theoretically, concomitant use of capsicum (including exposure to the capsicum in pepper spray) and cocaine might increase cocaine effects and the risk of adverse effects, including death (3).

THEOPHYLLINE <<interacts with>> CAPSICUM

Interaction Rating = Moderate Be cautious with this combination.

Severity = Moderate • Occurrence = Possible • Level of Evidence = D

Theoretically, oral administration of capsicum before or at the same time as theophylline might enhance theophylline absorption (14).

Interactions with Foods:

None known.

Interactions with Lab Tests:

BLEEDING TIME: Capsicum has led to increased fibrinolytic activity and may lead to prolonged times in coagulation studies (9).

Interactions with Diseases or Conditions:

DAMAGED SKIN: Capsicum is contraindicated in situations involving injured skin. Do not apply capsicum if the skin is open.
SURGERY: Capsicum has antiplatelet effects. Capsicum might cause excessive bleeding if used perioperatively. Tell patients to discontinue capsicum at least 2 weeks before elective surgical procedures.

Dosage/Administration:

ORAL: For swallowing dysfunction in the elderly, 1 lozenge containing 1.5 mcg of capsaicin is dissolved in the mouth before each meal (27).

SourceURL:file://localhost/Users/ruthruane/Downloads/Herbal%20Medicine-Newest.doc TOPICAL: For pain syndromes, including rheumatoid and osteoarthritis, neuropathy, and fibromyalgia, creams contain the active capsicum constituent capsaicin and are typically applied 3-4 times daily. It can take up to 14 days for the full analgesic effect. Most creams contain 0.025% to 0.075% capsaicin concentrations. Higher potency preparations may be used for diabetic neuropathy (1, 13). For back pain, capsicum-containing plasters providing 11 mg capsaicin/plaster or 22 mcg/cm2 of plaster applied have been used. The plaster is applied once daily in the morning and left in place for 4-8 hours (44, 45, 46).
For prurigo nodularis, 0.025% to 0.3% of the active capsicum constituent capsaicin 4-6 times daily has been used (48). Tell patients to make sure they wash their hands after applying capsaicin cream. Tell patients they can use a diluted vinegar solution to remove capsicum cream. The active constituent, capsaicin is not water washable. Warn against using capsicum preparations near the eyes or on sensitive skin (21).
INTRANASAL: For cluster headache, 0.1 mL of a 10 mM capsaicin suspension, providing 300 mcg/day of capsaicin, applied to the ipsilateral nostril, has been used. Applications of the suspension continued once daily until a burning sensation was no longer experienced (23, 43). A capsaicin 0.025% cream (Zostrix, Rodlen Laboratories) applied daily for 7 days has been used to treat acute cluster headache attacks (25). For migraine headache, application of capsaicin 0.075% to the nasal mucosa has been used (35).
For allergic rhinitis, a cotton wad soaked in 30 microM capsaicin solution applied for 15 minutes and repeated over 2 days has been used (30).
For perennial rhinitis, intranasal application of capsaicin solution providing 0.15 mg/dose for up to 7 doses over a 14-day period has been used (34). A capsaicin nasal spray 0.0033 mol once weekly for 5 weeks has also been used (42). A capsaicin nasal spray containing 15 mcg/mcL, 2 sprays applied 3 times daily for 3 days has also been used (44).
For sinonasal polyposis, 0.5 mL of a 30 mmol/L capsaicin solution applied to each nostril for 3 days followed by 0.5 mL of a 100 mmol/L capsaicin solution for 2 days has been used (41).

Due to severe pain associated with intranasal capsaicin administration, pretreatment with intranasal local anesthetic is usually used.

Editor's Comments:

In nature, capsaicin occurs only as a trans-stereoisomer. However, the cis-isomer called civamide also has activity. Some evidence suggests that civamide is more potent and causes less irritation than trans-capsaicin. Civamide is currently an investigational drug for migraine, osteoarthritis, and other pain-related conditions (29).
Products labeled capsaicin sometimes include nonivamide which is an adulterant or pelargonic acid vanillylamide, referred to as "synthetic capsaicin" (10).

Specific References: Cayenne

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• Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid= 786bafc6f6343634fbf79fcdca7061e1&rgn=div5&view= text&node=21:3.0.1.1.13&idno=21

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