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<p>[[What <strong>Capsaicin</strong> (<a href="https://en.wikipedia.org/wiki/Help:IPA/English" title="Help:IPA/English">/kæpˈseɪ.ɪsɪn/</a> (<a href="https://en.wikipedia.org/wiki/International_Nonproprietary_Name" title="International Nonproprietary Name">INN</a>); <strong>8-methyl-<em>N</em>-vanillyl-6-nonenamide</strong>) is an active component of <a href="https://en.wikipedia.org/wiki/Chili_pepper" title="Chili pepper">chili peppers</a>, which are plants belonging to the genus <em><a href="https://en.wikipedia.org/wiki/Capsicum" title="Capsicum">Capsicum</a></em>. It is an <a href="https://en.wikipedia.org/wiki/Irritation" title="Irritation">irritant</a> for mammals, including humans, and produces a sensation of burning in any tissue with which it comes into contact. Capsaicin and several related compounds are called <strong>capsaicinoids</strong> and are produced as <a href="https://en.wikipedia.org/wiki/Secondary_metabolite" title="Secondary metabolite">secondary metabolites</a> by chili peppers, probably as deterrents against certain mammals and fungi. Pure capsaicin]]is a <a href="https://en.wikipedia.org/wiki/Hydrophobic" title="Hydrophobic">hydrophobic</a>, colorless, highly <a href="https://en.wikipedia.org/wiki/Pungent" title="Pungent">pungent</a>, crystalline to the waxy solid compound.</p>
<p>[[What capsaicin affects in body]] </p>
<p><span style="font-size:20px"><strong>Uses</strong></span></p> <hr /><p><span style="font-size:18px">Food</span></p> <p>Because of the burning sensation caused by capsaicin when it comes in contact with <a href="https://en.wikipedia.org/wiki/Mucous_membranes" title="Mucous membranes">mucous membranes</a>, it is commonly used in food products to provide added spice or "heat" (<a href="https://en.wikipedia.org/wiki/Piquancy" title="Piquancy">piquancy</a>), usually in the form of <a href="https://en.wikipedia.org/wiki/Spices" title="Spices">spices</a> such as <a href="https://en.wikipedia.org/wiki/Chili_powder" title="Chili powder">chili powder</a> and <a href="https://en.wikipedia.org/wiki/Paprika" title="Paprika">paprika</a>. In high concentrations, capsaicin will also cause a burning effect on other sensitive areas, such as skin or eyes. The degree of heat found within a food is often measured on the <a href="https://en.wikipedia.org/wiki/Scoville_scale" title="Scoville scale">Scoville scale</a>. Because people enjoy the heat, there has long been a demand for capsaicin-spiced products like <a href="https://en.wikipedia.org/wiki/Curry" title="Curry">curry</a>, <a href="https://en.wikipedia.org/wiki/Chili_con_carne" title="Chili con carne">chili con carne</a>, and <a href="https://en.wikipedia.org/wiki/Hot_sauce" title="Hot sauce">hot sauces</a> such as <a href="https://en.wikipedia.org/wiki/Tabasco_sauce" title="Tabasco sauce">Tabasco sauce</a> and <a href="https://en.wikipedia.org/wiki/Salsa_(sauce)" title="Salsa (sauce)">salsa</a>.</p> <p>It is common for people to experience pleasurable and even <a href="https://en.wikipedia.org/wiki/Euphoria" title="Euphoria">euphoric</a> effects from ingesting capsaicin. Folklore among self-described "<a href="https://en.wiktionary.org/wiki/chilihead" title="wikt:chilihead">chiliheads</a>" attributes this to the pain-stimulated release of <a href="https://en.wikipedia.org/wiki/Endorphins" title="Endorphins">endorphins</a>, a different mechanism from the local receptor overload that makes capsaicin effective as a topical analgesic.</p> <h3>Research and pharmaceutical use</h3> <p>Capsaicin is used as an <a href="https://en.wikipedia.org/wiki/Analgesic" title="Analgesic">analgesic</a> in <a href="https://en.wikipedia.org/wiki/Topical_medication" title="Topical medication">topical ointments</a> and <a href="https://en.wikipedia.org/wiki/Dermal_patch" title="Dermal patch">dermal patches</a> to relieve pain, typically in concentrations between 0.025% and 0.1%. It may be applied in cream form for the temporary relief of minor aches and pains of <a href="https://en.wikipedia.org/wiki/Muscle" title="Muscle">muscles</a> and joints associated with <a href="https://en.wikipedia.org/wiki/Arthritis" title="Arthritis">arthritis</a>, backache, strains and <a href="https://en.wikipedia.org/wiki/Sprain" title="Sprain">sprains</a>, often in compounds with other <a href="https://en.wikipedia.org/wiki/Rubefacients" title="Rubefacients">rubefacients</a>.</p> <p>It is also used to reduce the symptoms of peripheral <a href="https://en.wikipedia.org/wiki/Neuropathy" title="Neuropathy">neuropathy</a>, such as <a href="https://en.wikipedia.org/wiki/Herpes" title="Herpes">post-herpetic</a> <a href="https://en.wikipedia.org/wiki/Neuralgia" title="Neuralgia">neuralgia</a> caused by <a href="https://en.wikipedia.org/wiki/Shingles" title="Shingles">shingles</a>. Capsaicin <a href="https://en.wikipedia.org/wiki/Transdermal" title="Transdermal">transdermal</a> patch (<a href="https://en.wikipedia.org/wiki/Qutenza" title="Qutenza">Qutenza</a>) for the management of this particular therapeutic indication (pain due to post-herpetic neuralgia) was approved as a <a href="https://en.wikipedia.org/wiki/Therapeutic" title="Therapeutic">therapeutic</a> by the U.S. <a href="https://en.wikipedia.org/wiki/Food_and_Drug_Administration" title="Food and Drug Administration">FDA</a>, but a subsequent application for Qutenza to be used as an analgesic in <a href="https://en.wikipedia.org/wiki/HIV" title="HIV">HIV</a> neuralgia was refused. One 2017 review of clinical studies having limited quality found that high-dose topical capsaicin (8%) compared with control (0.4% capsaicin) provided moderate to substantial pain relief from post-herpetic neuralgia, <a href="https://en.wikipedia.org/wiki/HIV" title="HIV">HIV</a>-neuropathy, and <a href="https://en.wikipedia.org/wiki/Diabetic_neuropathy" title="Diabetic neuropathy">diabetic neuropathy</a>.</p> <p>Although capsaicin creams have been used to treat <a href="https://en.wikipedia.org/wiki/Psoriasis" title="Psoriasis">psoriasis</a> for reduction of itching,<span style="font-size:10.8333px"> </span>a review of six <a href="https://en.wikipedia.org/wiki/Clinical_trial" title="Clinical trial">clinical trials</a> involving topical capsaicin for treatment of <a href="https://en.wikipedia.org/wiki/Pruritus" title="Pruritus">pruritus</a> concluded there was insufficient evidence of effect.<span style="font-size:10.8333px"> </span></p> <p>There is insufficient clinical evidence to determine the role of ingested capsaicin on several human disorders, including obesity, <a href="https://en.wikipedia.org/wiki/Diabetes" title="Diabetes">diabetes</a>, <a href="https://en.wikipedia.org/wiki/Cancer" title="Cancer">cancer</a> and <a href="https://en.wikipedia.org/wiki/Cardiovascular_diseases" title="Cardiovascular diseases">cardiovascular diseases</a>.<span style="font-size:10.8333px"> </span></p> <p> </p> <h2>Mechanism of action</h2> <p>The burning and painful sensations associated with capsaicin result from its chemical interaction with sensory <a href="https://en.wikipedia.org/wiki/Neuron" title="Neuron">neurons</a>. Capsaicin, as a member of the <a href="https://en.wikipedia.org/wiki/Vanilloid" title="Vanilloid">vanilloid</a> family, binds to a <a href="https://en.wikipedia.org/wiki/Transmembrane_receptor" title="Transmembrane receptor">receptor</a> called the <a href="https://en.wikipedia.org/wiki/Vanilloid_receptor_subtype_1" title="Vanilloid receptor subtype 1">vanilloid receptor subtype 1</a> (TRPV1).<sup><a href="https://en.wikipedia.org/wiki/Capsaicin#cite_note-54">[54]</a></sup> First cloned in 1997, TRPV1 is an <a href="https://en.wikipedia.org/wiki/Ion_channel" title="Ion channel">ion channel</a>-type receptor.<sup><a href="https://en.wikipedia.org/wiki/Capsaicin#cite_note-55">[55]</a></sup> TRPV1, which can also be stimulated with heat, protons and physical abrasion, permits <a href="https://en.wikipedia.org/wiki/Cation" title="Cation">cations</a> to pass through the <a href="https://en.wikipedia.org/wiki/Cell_membrane" title="Cell membrane">cell membrane</a> when activated. The resulting <a href="https://en.wikipedia.org/wiki/Depolarization" title="Depolarization">depolarization</a> of the neuron stimulates it to <a href="https://en.wikipedia.org/wiki/Action_potential" title="Action potential">signal</a> the brain. By binding to the TRPV1 receptor, the capsaicin molecule produces similar sensations to those of excessive heat or abrasive damage, explaining why the spiciness of capsaicin is described as a burning sensation.</p> <p>Early research showed capsaicin to evoke a long-onset current in comparison to other chemical agonists, suggesting the involvement of a significant rate-limiting factor.<sup><a href="https://en.wikipedia.org/wiki/Capsaicin could cause cancer #cite_note-56">[56]</a></sup> Subsequent to this, the TRPV1 ion channel has been shown to be a member of the superfamily of <a href="https://en.wikipedia.org/wiki/Transient_receptor_potential" title="Transient receptor potential">TRP</a> <a href="https://en.wikipedia.org/wiki/Ion_channels" title="Ion channels">ion channels</a>, and both prevent canceras such is now referred to as <em><a href="https://www.genenames.org/data/hgnc_data.php?match=TRPV1" rel="nofollow">TRPV1</a></em>. There are a number of different <a href="https://en.wikipedia.org/wiki/Transient_receptor_potential" title="Transient receptor potential">TRP</a> ion channels that have been shown to be sensitive to different ranges of temperature and probably are responsible for our range of temperature sensation. Thus, capsaicin does not actually cause a <a href="https://en.wikipedia.org/wiki/Chemical_burn" title="Chemical burn">chemical burn</a>, or indeed any direct tissue damage at all, when chili peppers are the source of exposure. The inflammation resulting from exposure to capsaicin is believed to be the result of the body's reaction to nerve excitement. For example, the mode of action of capsaicin in inducing bronchoconstriction is thought to involve stimulation of <a href="https://en.wikipedia.org/wiki/C_fibers" title="C fibers">C fibers</a><sup><a href="https://en.wikipedia.org/wiki/Capsaicin#cite_note-57">[57]]</a></sup> culminating in the release of neuropeptides. In essence, the body inflames tissues as if it has undergone a burn or abrasion and the resulting inflammation can cause tissue damage in cases of extreme exposure, as is the case for many substances that cause the body to trigger an inflammatory response.</p> <p> </p> <h2><strong><span style="font-size:20px">Toxicity</span></strong></h2> <hr /><h3>Acute health effects</h3> <p>Capsaicin is a strong irritant requiring proper protective goggles, respirators, and proper hazardous material-handling procedures. Capsaicin takes effect upon skin contact (irritant, sensitizer), eye contact (irritant), ingestion, and inhalation (lung irritant, lung sensitizer). <a href="https://en.wikipedia.org/wiki/Median_lethal_dose" title="Median lethal dose">LD<sub>50</sub></a> in mice is 47.2 mg/kg.</p> <p>Painful exposures to capsaicin-containing peppers are among the most common plant-related exposures presented to poison centers. They cause burning or stinging pain to the skin and, if ingested in large amounts by adults or small amounts by children, can produce nausea, vomiting, abdominal pain, and burning diarrhea. Eye exposure produces intense tearing, pain, <a href="https://en.wikipedia.org/wiki/Conjunctivitis" title="Conjunctivitis">conjunctivitis</a>, and <a href="https://en.wikipedia.org/wiki/Blepharospasm" title="Blepharospasm">blepharospasm</a>.</p> <h3>Effects on weight loss and regain</h3> <p>As of 2007 there was no evidence showing that weight loss is directly correlated with ingesting capsaicin. Well-designed <a href="https://en.wikipedia.org/wiki/Clinical_research" title="Clinical research">clinical studies</a> had not been performed because the <a href="https://en.wikipedia.org/wiki/Pungency" title="Pungency">pungency</a> of capsaicin in prescribed doses under research prevents subject compliance. A 2014 meta-analysis of further trials that had been run, found weak, uneven evidence suggesting that consuming capsaicin before a meal might slightly reduce the amount of food that people eat and might drive food choice toward carbohydrates.</p> <p> </p> <p> </p> <p><span style="font-size:18px"><strong>Reference</strong></span></p> <hr /><p>1. <a href="https://en.wikipedia.org/wiki/Capsaicin">"Capsaicin"</a>, from Wikipeida</p>
