Capsaicin for Pain
If you have ever eaten a chili pepper, then you know how painful it can be. What you may not have noticed is that afterwards the nerves that were affected were numb to other sensations. This desensitization is caused by a chemical called capsaicin found in peppers.
Capsaicin is a unique chemical compound that excites the nerves followed by a long period of inactivity. This phenomenon is known as defunctionalisation and is why capsaicin has been used as a remedy for certain kinds of pain conditions.
How Capsaicin Causes Pain Relief
Capsaicin is a chemical compound produced by chili peppers, probably intended to ward off mammals and fungi from preying on the plant. When ingested, capsaicin causes a burning sensation upon contact with a mucus membrane.
Because capsaicin is a vanilloid compound, it binds to the vanilloid receptor subtype 1 (TRPV1) on sensory nerve cells. This binding opens an ion channel that allows cations into the neuron. This kind of stimulation in sensory nerve cells sends a nerve impulse that a burning stimulus has been encountered.
It is believed that capsaicin overexcites neurons enough that it depletes its supply of a neuropeptide called substance P. Substance P is an essential messenger protein that transmits impulses from nerve endings. After an initial burning sensation, capsaicin numbs pain by greatly lowering the presence of substance P.
How Capsaicin Is Used to Treat Chronic Pain
Capsaicin is used to treat a wide variety of pain conditions including arthritis, muscle strains, backache, neuropathy, fibromyalgia, migraines, surgical pain, and joint sprains. This chemical is normally applied to the problem area in the form of a topical cream or a dermal patch. You may apply the medicine multiple times a day.
Over the counter versions of capsaicin medications that do not require a prescription typically have a concentration ranging from 0.025 to 0.1 percent capsaicin content. Prescribed medications may have much higher concentrations and typically are used to treat more persistent or severe pain conditions. Prescription versions of this medication are most commonly used to treat arthritis or diabetic neuropathy.
If you are using the prescription strength version of capsaicin (which may be as high as 8 percent), then your doctor may apply up to four patches on the problem area for up to 60 minutes. This application may provide pain relief for several months.
Although capsaicin is a relatively risk-free therapy for many chronic pain conditions, there are some things you should keep in mind. First, you should know that capsaicin is a very powerful irritant—in fact, this is the same compound used in pepper sprays—which can cause burning pain if applied near the eyes or mouth.
If you are allergic to chili peppers, you should tell your doctor or pharmacist, so that they can recommend an alternative therapy option. If you experience pain, swelling or blistering, you should contact your physician immediately.
The most common side effects of capsaicin use are
- Burning feeling at the site of application, normally only for a temporary period after application
- Small bumps
There is the risk of overdose with capsaicin. If you find the patient unconscious, having a seizure or difficulty breathing, call 911 immediately.
To minimize exposure to children or pets, you should store this medication tightly sealed in a container and out of reach. You may store capsaicin at room temperature.
The Efficacy of Capsaicin
A number of studies of the effectiveness of capsaicin have been published in recent years. Most of the more reliable studies focused on its use as a pain reliever for serious conditions like neuropathy. One meta-study that analyzed the results of seven prior trials examined more than 2,440 patients suffering from moderate to severe neuropathic pain.
The study participants were treated with 8 percent capsaicin and patients were monitored for at least 8 weeks. Only minor side effects like redness or burning sensations for temporary periods were found among participants. Some participants were given authentic capsaicin treatments of varying concentrations. A control group was given a placebo or a treatment with very low concentration capsaicin.
Although the meta-study authors concluded that many of the trials were of moderate to low quality, the overall results did support the contention that high concentration capsaicin did produce more pain relief than the control treatments. Not only did neuropathy patients witness improvements in pain symptoms, but they also reported improvements in sleep, depression, fatigue, and quality of life.
Another study published in 2017 evaluated 60 patients with pelvic neuralgia who used a high-concentration capsaicin patch with 8 percent capsaicin. Of the 60 study participants, 24 reported “much improved” or “very much improved” pain symptoms following treatment.
Although this study only utilized patients who were treated with capsaicin, i.e., without a control group, and only a statistically small population at that, the results reinforce the idea that a sizable portion of capsaicin users benefit from the therapy.
Should You Try Capsaicin?
Given that the current understanding of capsaicin’s efficacy as a pain reliever is incomplete, there is still some debate about how effective capsaicin is for many kinds of chronic pain conditions. There are some conditions like arthritis, neuropathy and lower back pain that have been treated with capsaicin in clinical studies and shown encouraging results, but in many cases, the studies were not quite large or rigorous enough to be truly convincing.
However, you should keep in mind that capsaicin therapies typically have low risks. So, if you want to try out capsaicin in non-prescription strength, then there are no real reasons why you shouldn’t—except if you are allergic to capsaicin or chili peppers. If you do intend to try capsaicin, you should discuss it with your physician beforehand. Your doctor will let you know if the capsaicin may cross-react with any other medications you are taking or have recommendations on how to use it. If you do not have any adverse reactions, then you may discuss trying a higher concentration version.
Article written by: Dr. Robert Moghim – CEO/Founder Colorado Pain Care
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