Applications Capsaicin

ZITTEL T T, MEILE T, HUGE A, KREIS M E, BECKER H D, JEHLE E c (2001) Preoperative intraluminal application of capsaicin increases postoperative gastric and colonic motility in rats. J Gastrointest Surg. 5 503-13. 

Capsaicin achieves pain relief by depleting substance P from sensory neurons in the spine, thereby decreasing pain transmission. Capsaicin is not effective for acute pain up to 2 weeks may be necessary before pain relief is appreciated. Most patients experience a local burning sensation at the site of application. The discomfort usually does not result in... 

As with other counterirritants, capsaicin and its derivatives (i.e., capsicum and capsicum oleoresin) exert a warming or burning sensation. With repeated application, desensitization occurs, and the burning sensation subsides. This typically occurs within the first 1 to 2 weeks. After discontinuation,... 

Recommend appropriate pharmacologic therapy and educate on proper use. If a counterirritant is recommended, counsel patients on the irritant effect of the product and recommend washing hands immediately after use and to avoid heating pads. For patients using a capsaicin product, emphasize that adherence to regular application is required for effectiveness. 

To be effective, capsaicin must be used regularly, and it may take up to 2 weeks to work. It is well tolerated, but some patients experience temporary burning or stinging at the site of application. Patients should be warned not to get the cream in their eyes or mouth and to wash their hands after application. 

The predominant adverse effect of clinical use of capsaicin is the burning sensation it produces. Many find it intolerable, and withdrawal rates from clinical studies have been reported as 30% or higher (Szallasi and Blumberg 1999). Excessive ingestion of chili peppers can cause visceral pain, increased peristalsis and diarrhea (Gruenwald 1998). Excessive external application can cause blister and ulcer formation. Very high doses can cause a serious hypothermia. 

For external use only Avoid contact with eyes or broken or irritated skin. Use care when handling contact lenses following application of capsaicin. 

Capsaicin acts by interfering with substance P, which enhances the pain of inflammation. Elevated concentrations of substance P are found in areas of nociceptive stimulation. Topical application of capsaicin causes the release and depletion of substance P in C fibers. This mechanism limits the use of capsaicin to areas of localized pain. 

Preexposure to menthol and capsaicin can desensitize the response to other stimuli, i.e. the thermal response to a warm solution or the irritation upon a second application of capsaicin (26,27). After capsaicin desensitization, the nerves no longer respond to burning or stinging but still give sensations of numbness or warmth. This effect is most noticeable upon further stimulation with capsaicin and less for the irritants, cinnamic aldehyde and NaCl. This sensitization and the fact that these sensations build in intensity on repeat application differentiate them from the "basic tastes", which adapt to the sensation on repeated application. 

Low, P.A., Opfer-Gehrking, T.L., Dyck, P.J., Litchy, W.J., O Brien, P.C. Double-blind, placebo-controlled study of the application of capsaicin cream in chronic distal painful polyneuropathy. Pain 1995, 62, 163-168,... 

Marabini, S., Ciabatti, P.G., Polli, G., Fusco, B.M., Geppetti, P. Beneficial effects of intranasal applications of capsaicin in patients with vasomotor rhinitis, Eur. Arch, of Oto-Rhino-Laryngol. 1991, 248, 191-194. 

This pungent product is responsible for the intense irritant effects of topical Capsicum preparations. Repeated application of capsaicin can deplete and prevent reaccumulation of substance P, an endogenous mediator of pain impulses from the periphery to the CNS. Since the early 1990s, capsaicin cream has been available in the U.S. as an approved drug for relief of postherpetic neuralgia and pain due to diabetic neuropathy and osteoarthritis. 

Over-stimulated pain receptors eventually release endorphins, which are natural pain-killing molecules. VRi receptors can lose their responsiveness after prolonged exposure to capsaicin which is why those who eat a lot of spicy food build up a tolerance to chilli. This is also why capsaicin is used in formulations designed to ease pain, repeated application of which desensitise the nerves. Regular application of a capsaicin cream to aching joints can relieve pain and increase flexibility. Chemotherapy for cancer patients often results in oral pain and sucking capsaicin-laced butterscotch has proved effective. 

All these aspects have been recently studied in two publications (10.13). which standardized the dilution test for pungency and clearly established correlations with the estimates of total, and even individual, capsaicinoids. These papers also review the earlier attempts at standardisation. Two approaches are possible use of a fairly homogenous panel to determine the threshold pungency response due to the stimuli or use of a general panel to determine the average threshold of the panel for the stimuli. The second value will have wider applicability in use situations but the first value should be useful for correlative work. The two methods approach one another when panels are screened and trained to avoid all bias factors, and when carefully planned dilution levels, details of panel procedure, treatment of data, and expression of results are adopted. In fact, the results published in the two independent studies (10.13). show close values, 17+0.9 million for natural capsaicinoids and 16.1+0.6 million for pure capsaicin and dihydrocapsaicin. 

Exposure to other RCAs causes similar dermal effects. CN is a more potent irritant than CS. In a human study involving dermal application, CN (0.5 mg) powder caused irritation and erythema when on the skin for 60 min (Holland and White, 1972). It took 20 mg CS to cause similar effects for the same duration of exposure. Exposure to 5% capsaicin pepper spray causes immediate and severe erythema and edema in the skin (Herman et al, 1998). Similarly, pepper ball pellets fired at individuals will cause erythema, pain, and edema at the site of impaet. The initial point of contact may become infected, scar, or heal with hyperpigmentation (Hay et al, 2006). 

Bunker, C.B., Cerio, R., Bull, H.A., Evans, J., Dowd, P.M., Foreman, J.C. (1991). The effect of capsaicin application on mast cells in normal human skin. Agents Actions 33 195-6. 

Campbell, E., Bevan, S., Drary, A. (1993). Clinical applications of capsaicin and its analogues. In Capsaicin in the Study of Pain (J. Wood, ed.), pp. 255-69. Harcourt Brace Co., London. 

Topical therapy may be of some benefit to the PHN patient. They are used after the skin lesions have healed but cannot be used on periocular tissue Topical lidocaine patches for analgesia is one such treatment. Capsaicin cream has also been used and may provide pain relief within 2 to 4 weeks of treatment. The cream is applied three to four times daily to the area of painful skin. Approximately 30% of treated patients experience burning, stinging, or redness of the skin on initial application, but with repeated use these reactions usually diminish or subside. 

Capsaicin is the compound responsible for the characteristic spicy flavor of jalapeho and habahero peppers. Although it first produces a burning sensation on contact with the mouth or skin, repeated application desensitizes the area to pain. This property has made it the active ingredient in several topical creams for treatment of chronic pain. Capsaicin has also been used as an animal deterrent in pepper sprays, and as an additive to make birdseed squirrel-proof In Chapter 1, we discuss the structure, bonding, and properties of organic molecules like capsaicin. 

Capsaicin is supplied pharmaceutically as a cream, gel. or lotion. The First application of the piepatation produces intense pain and irritation at the site of application, but usually no skin reaction occurs. Repeated applications cause desensitization, and eventually analgesic and anti-inflammatory effects occur., Stimulation of afferent nerve tracts causes a heat. sensation. 

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