Making Sense Of Over-The-Counter Topical Pain Relievers
When you think of creams for aching muscles and joints the first thing that comes to mind is probably the pungent smell. I always think of Tiger Balm and Ron Smith’s Muay Thai School. It was 1998 and I was wandering through random martial arts gyms, while finishing up pharmacy school. I had just finished my second class and saw Ron take a huge container of Tiger Balm and rub down the shoulders of Jermaine Andre. The smell permeated the room, easily overpowering the distinct odor from the 20 of us who had just finished training.
Aches and pains are a regular part of training and using Tiger Balm or other topical products is commonplace in locker rooms for all sports. As grapplers we tend to get these injuries a bit more often than others and knowing your way around the pharmacy aisle can get you back out there just a little quicker.
Transient receptor potential (TRP) channels are heavily involved in the sensation of pain. For the sake of this article, we’ll keep the details to a minimum, but still give you the information needed so that you’ll have a basic understanding of what topical analgesics are doing. There are roughly 30 TRP channels (more are discovered all the time). TRP channels are responsible for sensations that we associate with our senses: pain, taste, pressure, vision, temperature, etc… Activating the TRP channel produces the sensation associated with it. The channels associated with pain are also used for other touch-based stimuli, such as heat and cold. This property of TRP channels is why OTC analgesics work.
Essentially, you have a doorway. On one side you have a bunch of guys waiting to come through. We’ll call these guys: Pain and Cold (or Hot). They all want to go through the door, but only one can fit at a time. We don’t like Pain very much and we’ve invited Cold and a dozen of his buddies. Now that Cold outnumbers Pain the door is being filled with Cold and all his friends until they’ve gone through. As a result Pain has been stopped temporarily.
OTC products are counterirritants and work because of the principles outlined above. The cream makes you feel hot/cold and while that sensation is being felt, you’re not able to feel pain as distinctly. They are used for a variety of minor aches and pains of the joints and muscles. Unlike true analgesics, which depress skin receptors, counterirritants are effective through the stimulation. Now, it’s time to look at some of the products. For the next section we’ll go over the most common ingredients. With this information you’ll be able to read the label of the product in question and have a good idea of what it is and what it’s intended to do.
Capsaicin, derived from chili peppers, is one of the most widely used natural ingredients in topical analgesics. There are approximately a 1,000 different patented products, which include capsaicin as an active ingredient. The strength/concentration of these products ranges from 0.025% to 0.075%. Capsaicin use may be limited, due to the need for a period of desensitization in some patients. Initial applications of the product may cause painful burning until the patient’s skin is used to it, usually a few days. Capsaicin has been shown to be effective in treating osteoarthritis (OA) of the hands, hips and knees. Capsaicin products can be used for acute or chronic pain and have the most data to support effectiveness.
If you experience pain, swelling or blistering, stop using the product immediately. Wash it off with cool water and seek medical attention as needed.
Do not apply to burns, broken/damaged skins, or areas with infections
Do not apply to eyes and mucous membranes, or any areas with sensitive skin.
Wash your hands thoroughly after using
Do NOT apply this product before training if there is any chance that it may rub off on someone else and/or on a part of you that you don’t want it on.
While salicylates have a long history of use for the treatment of pain, peer-reviewed data is lacking. A meta-analysis of available literature has shown that salicylate-containing products appear to be effective for short-term pain and chronic pain. In the trials reviewed, positive response was seen in just over half those using these products, compared to a third using placebo. Studies have been published to determine the amount of salicylate absorbed from topical agents. In a study of trolamine salicylate and methyl salicylate the salicylic acid from the topical agent could not be detected in the patients using trolamine salicylate, while the patient’s using methyl salicylate had detectable levels within an hour.
Menthol can be synthesized or obtained naturally from mint oils and acts as a counter irritant by causing a cooling sensation when applied to the skin. Camphor acts in the same way. As counterirritants the mechanism of action is the same as capsaicin, however, available data to support efficacy is more limited. Menthol gel was shown to improve function in patients with OA of the knee; however, pain wasn’t significantly different in the placebo vs menthol group.
It Burns! FDA Warning:
Reports of Serious Burns Due to Topical Pain Relievers, FDA Issues Warning September 2012
The U.S. Food and Drug Administration (FDA) is alerting the public that certain over-the-counter (OTC) topical pain relievers have been associated with rare cases of serious skin injuries (eg, first- to third-degree chemical burns) at the application site. In some cases, hospitalization has been required.
OTC topical pain relievers are available as single- or combination-ingredient products that contain menthol, methyl salicylate, or capsaicin, and are marketed under brand names such as BenGay®, Capzasin®, Icy Hot®, and Mentholatum®. The formulations include creams, lotions, ointments, and patches.
Consumers who experience signs of skin injury (eg, pain, swelling, or blistering) following application of these products should discontinue their use and seek immediate medical attention. When recommending these pain relievers, healthcare providers should counsel patients about their appropriate use and the risk of burns.
Wrapping It Up
At the end of the day, most topical analgesics are going to be relatively interchangeable, especially for acute muscle or joint pain. If you have arthritis, there is enough data to recommend a capsaicin based product over the others. The most commonly seen product is Zostrix and generic brands are available as well. When using capsaicin to start with a lesser strength product to assess tolerance and move to higher concentrations if needed and it’s tolerated.
For other types of minor to moderate joint and muscle pain I’d suggest seeing what you have around the house. If you have to go to the store, choose a product based on price, odor, and ingredients. There are literally thousands of different products available and I highly recommend using a generic/store brand, much cheaper and the same efficacy. Many products will be combinations of salicylates and menthol/camphor. In these cases make sure that the ingredient is methyl salicylate, not trolamine.