Icy Hot. Ben Gay. Tiger Balm. These are just a few of the many over-the-counter topical (meaning, applied to the skin) pain relieving products (TPRPs) on the market. They vary by type, and of course active/ therapeutic ingredients.
There are also prescription TPRPs that contain medications like ibuprofen, aspirin or opioid derivatives (Rx TPRPs are not necessarily more effective than OTC ones).
These products generally are OK for aches and pains affecting muscles, tendons, joints and sometimes nerves; not so much for acute injuries involving swelling. And, they are effective only for superficial areas such as elbows and wrists, as depth of penetration is limited.
So far, research shows some benefit in reducing pain, but nothing dramatic. Anecdotal evidence on their effectiveness obviously differs wildly from person to person. This is mostly due to the fact that pain has both physical and mental components to it, and different people perceive pain differently.
Topical pain relief products come in creams, gels, ointments, patches and sometimes sprays. They are usually manufactured with a “delivery agent,” a substance that binds to the active ingredient and penetrates the skin where it diffuses down to the target tissue. The delivery agent, therefore, is critical to the products potency.
There are three basic ways TPRPs work:
(1) analgesia – reducing inflammation
(2) nerve signal inhibition
The medicinal products use analgesia to reduce pain; this includes those that contain ibuprofen or aspirin (acetylsalicylic acid). Botanicals such as arnica, boswellia serrata, devil’s claw and comfrey are herbs associated with pain relief and are found in many TPRPs. Their mechanism of action is probably via inflammation reduction by acting as a blocking agent in inflammatory reactions.
Capsaicin is the compound that gives hot peppers their perceived heat. Products utilizing this as the active ingredient are more suited for nerve-related pain (neuralgias) like post-herpetic neuralgia, trigeminal neuralgia or a peripheral nerve entrapment condition like carpal tunnel syndrome. What it does is bind to the ends of nerves that send chronic (slow) pain signals which causes them to discharge their neurotransmitter substance P (the substance that transfers the pain signal from nerve cell to nerve cell along the nerve) until it is depleted, effectively deadening the nerve temporarily.
The counter-irritants use menthol and/or camphor, substances that seem to affect cold receptors in the skin. Like ice, it sends a cooling sensation to the brain which may “scramble” or interfere with the pain signal coming from the painful area, thus reducing the perception of pain even though the skin temperature remains the same. Rubbing a sore wrist is basically the same thing — creating more nerve signals (pressure, friction) to compete with the pain signals, thus diluting their impact.
So should you try topical pain relief products? The obvious benefit is that they target only the area of pain. With oral pain relief medications, Rx and OTC, the reach is systemic as the medication is delivered in the blood stream to all body tissues except the brain. This creates a new set of problems (side effects) like nausea, muscle cramps and even renal damage.
On the other hand topical pain relief products don’t reach the target area as well as oral medications. The skin is designed to be impregnable to most external substances, so even if the medicine is able to penetrate, it is at a much lower dosage. This is significant only for the analgesic TPRPs, as they have to reach all the way down to the painful tissue. With the counter-irritants, penetration is not so much an issue as they work on sensory nerve endings that are close to the surface of the skin.
One product that I ran across seems to be effective for a lot of people, at least anecdotally, based on its reviews. It is called Penetrex and contains arnica, boswellia extract, MSM, vitamin B6 and a special delivering agent. If you have chronic pain affecting tendons, muscles and/or superficial joints, it’s worth giving it a try. As a matter of fact, it wouldn’t hurt to try the different TPRPs you find OTC at your nearest drugstore; it’s preferable to oral pain relief products (pills, tablets and liquids) any day, as far as safety is concerned.