From the Research
Capsaicin is the primary substance that stimulates type A pain receptors, as it activates TRPV1 receptors located on A-delta nerve fibers, which are responsible for sharp, localized pain sensations. Found naturally in chili peppers, capsaicin initially causes a burning sensation by depolarizing these pain receptors, but with continued use, it leads to desensitization and depletion of substance P, a key neurotransmitter involved in pain signaling, resulting in reduced pain perception over time 1. This mechanism makes capsaicin-containing products effective for treating neuropathic pain conditions like postherpetic neuralgia and diabetic neuropathy. Other substances that can stimulate type A pain receptors include:
- Certain acids
- Extreme temperatures (particularly heat)
- Mechanical pressure that reaches the threshold for nociception The activation of these receptors triggers the fast-conducting myelinated A-delta fibers, resulting in the quick, sharp pain that serves as an immediate protective warning signal to the body. According to a recent study, the use of capsaicin as a treatment for pain has shown therapeutic efficacy in patients with Morton's neuroma, a painful foot condition associated with compression of one of the digital nerves 1. Additionally, a review of pain pathways and potential new targets for pain relief highlights the importance of understanding the mechanisms of pain and the various receptors responsible for detecting pain, including TRPV1 receptors 2.
Some key points to consider when using capsaicin to stimulate type A pain receptors include:
- The initial burning sensation caused by capsaicin can be intense, but it typically subsides with continued use
- Capsaicin can be used topically in creams or patches, typically in concentrations of 0.025% to 0.1%
- The desensitization and depletion of substance P caused by capsaicin can lead to reduced pain perception over time
- Capsaicin-containing products can be effective for treating neuropathic pain conditions, but may not be suitable for all types of pain.
It's also worth noting that other studies have investigated the use of capsaicin as a treatment for various types of pain, including neuropathic pain and musculoskeletal pain 3, 4, 5. However, the most recent and highest quality study on this topic is 1, which provides the most up-to-date information on the use of capsaicin to stimulate type A pain receptors.