Description
Simple
A medication used to relieve pain in the muscles and joints.
Clinical
A topical analgesic agent used for the symptomatic relief of neuropathic pain associated with post-herpetic neuralgia, as well as other muscle and joint pain.
Overview
Capsaicin is most often used as a topical analgesic and exists in many formulations of cream, liquid, and patch preparations of various strengths; however, it may also be found in some dietary supplements. Capsaicin is a naturally-occurring botanical irritant in chili peppers, synthetically derived for pharmaceutical formulations. The most recent capsaicin FDA approval was Qutenza, an 8% capsaicin patch dermal-delivery system, indicated for neuropathic pain associated with post-herpetic neuralgia.
Pharmacology
Indication
The capsaicin 8% patch is indicated in the treatment of neuropathic pain associated with post-herpetic neuralgia. There are multiple topical capsaicin formulations available, including creams and solutions, indicated for temporary analgesia in muscle and join pain as well as neuropathic pain.
Pharmacodynamic
Capsaicin is a TRPV1 receptor agonist. TRPV1 is a trans-membrane receptor-ion channel complex activated by temperatures higher than 43 degrees Celsius, pH lower than 6, and endogenous lipids. When activated by a combination of these factors, the channel can transiently open and initiate depolarizati... Read more
Mechanism of action
Capsaicin has been shown to reduce the amount of substance P associated with inflammation - however this is not believed to be its main mechanism in the relief of pain [ Read more
Absorption
**Oral**: Following oral administration, capsaicin may be absorbed by a nonactive process from the stomach and whole intestine with an extent of absorption ranging between 50 and 90%, depending on the animal [ Read more
Protein binding
Information currently not available.
Volume of distribution
Information currently not available.
Clearance
Information currently not available.
Half life
Following oral ingestion of equipotent dose of 26.6 mg of pure capsaicin, the half life was approximately 24.9 ± 5.0 min [ Read more
Route of elimination
It is proposed that capsaicin mainly undergoes renal excretion, as both the unchanged and glucuronide form. A small fraction of unchanged compound is excreted in the feces and urine. _In vivo_ animal studies demonstrates that less than 10 % of an administered dose was found in faces after 48 h [ Read more
Toxicity
Acute oral LD50 and dermal LD50 in mouse are 47.2 mg/kg and >512 mg/kg, respectively [MSDS]. Capsaicin is shown to be mutagenic for bacteria and yeast [MSDS].
Capsaicin can cause serious irritation, conjunctivitis and lacrimation via contact with eyes. It induces a burning sensation and pain in c...
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Adverse Effects
Effect | Regions | Age Groups | Incidences | Evidence Type |
---|---|---|---|---|
Supraventricular arrhythmia | US |
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|
Clinical Trial |
Central Line Infection | US |
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Clinical Trial |
Central Line Infection | US |
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|
Clinical Trial |
Neutropenia | US |
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|
Clinical Trial |
Central Line Infection | US |
|
|
Clinical Trial |
Neutropenia | US |
|
|
Clinical Trial |
Neutropenia | US |
|
|
Clinical Trial |
Supraventricular arrhythmia | US |
|
|
Clinical Trial |
Neutropenia | US |
|
|
Clinical Trial |
Supraventricular arrhythmia | US |
|
|
Clinical Trial |
Supraventricular arrhythmia | US |
|
|
Clinical Trial |
Central Line Infection | US |
|
|
Clinical Trial |
Central Line Infection | US |
|
|
Clinical Trial |
Neutropenia | US |
|
|
Clinical Trial |
Supraventricular arrhythmia | US |
|
|
Clinical Trial |