Topical pain relievers: are they as good and safe as they say?

In 2021 over 50 million US adults experienced chronic pain.[1] As our population gets older; it is likely that this number will only increase. Topical pain relievers have many benefits and can help a large portion of this group. But what exactly are they and how can they help?

Topical pain relievers, also called topical analgesics, are medicines directly applied to the skin where there is pain. The medicine gets absorbed into the outer skin layers to reach an effective concentration in the underlying tissue. Topical pain relievers don’t go deeper, so they don’t enter the bloodstream. This significantly lowers the risk of side-effects or harm to the body. It’s a local treatment, just treating the muscles, ligaments, tendons, and nerves in the affected area. 

What kinds of topical pain relievers are there?

There are many topical pain relievers, and it is not one-size-fits-all. Depending on their active ingredients, each topical pain reliever works in its own unique way

Topical Nonsteroidal Anti-Inflammatory Drugs (NSAIDs), like the name suggests, reduce inflammation, and are often prescribed for painful or inflammatory conditions. The active ingredients often used: diclofenac, ketoprofen or ibuprofen are similar to those most common in oral NSAIDs. Studies show topical NSAIDs effectively treat acute (minor trauma, strains and sprains) and chronic pain (osteoarthritis or rheumatological disorders).[2]

Local anesthetics, like lidocaine, desensitize the skin and underlying tissue. Most research involving lidocaine has been done on conditions involving nerve pain (neuropathy), where it’s an effective and safe alternative to oral drugs. More studies on lidocaine for musculoskeletal pain are emerging. While studies are limited, most suggest it can be effective in treating lower back pain and osteoarthritis.[3]

Counterirritants are another common topical pain reliever. Their ingredients, like menthol, camphor, methyl salicylate and capsaicin are used alone or in combination. Like local anesthetics, they work by desensitizing the nerves in the skin and underlying tissue. All different counterirritants do this in their own way. 

The use of certain counterirritants, such as menthol, dates back centuries. In modern studies, menthol and methyl salicylate have been shown to be effective in relieving pain for muscle related injury, and menthol by itself has been shown to reduce pain perception during exercise.[4,5] Capsaicin has been researched a lot for nerve pain, where it’s been found effective. It also effectively reliefs musculoskeletal pain, although less effectively compared to the other counterirritants or NSAIDS.[6]

How is a topical pain reliever different from other drugs?

Pain relieving medicines come in different shapes and forms. Other than topically administrated pain relievers, oral, rectal, and transdermal medication are often used for pain relief. Though their names may suggest otherwise, these do all work in a similar way.

Oral and rectal medication is taken as capsules, liquids, or tablets. They are most often absorbed in the stomach or bowels before entering the blood. Transdermal medicine, like topical medication, is applied to the skin. However, unlike topical medication, transdermal medication is absorbed in the bloodstream and is only effective once there is a therapeutic concentration of the drug in the blood. This means that transdermal drugs, like rectal and oral medication, cause systemic effects. Topical pain relievers only act locally. 

What are the benefits of topical pain relievers over other drugs?

Topical pain relievers have the benefit of working locally. This means that for most topical pain relievers side effects are local too – skin reactions in the applied area. Used correctly, systemic side effects or harm are extremely rare. 

The localized nature of the treatment also results in a very low drug interaction risk. With some products, you may have to refrain from bandaging the area or using it with other topical products. However, most can be safely added to any other medication regiment. This makes topical pain relievers a great and easy way to relief pain, by itself or with other pain medication. 

Beyond this, topical pain relievers are often faster acting, and easy to apply. Some cause a cooling or hot sensation, that can be felt in minutes, and most will provide pain relief for many hours. Due to all these benefits, patient compliance is higher than with many other drug types.

Topical pain relievers are an excellent way to relief pain. They can replace other pain-relieving drugs or can be complimentary to an existing pain treatment regimen.

Want to read more? 

Stanos SP. Topical agents for the management of musculoskeletal pain. J Pain Symptom Manage. 2007 Mar;33(3):342-55.

1. Rikard SM, Strahan AE, Schmit KM, Guy GP Jr.. Chronic Pain Among Adults - United States, 2019–2021. MMWR Morb Mortal Wkly Rep 2023;72:379–385. 
2. Moore RA, Tramèr MR, Carroll D, Wiffen PJ, McQuay HJ. Quantitative systematic review of topically applied non-steroidal anti-inflammatory drugs. BMJ. 1998 Jan 31;316(7128):333-8. 
3. Voute M, Morel V, Pickering G. Topical Lidocaine for Chronic Pain Treatment. Drug Des Devel Ther. 2021 Sep 29;15:4091-4103. 
4. Higashi Y, Kiuchi T, Furuta K. Efficacy and safety profile of a topical methyl salicylate and menthol patch in adult patients with mild to moderate muscle strain: a randomized, double-blind, parallel-group, placebo-controlled, multicenter study. Clin Ther. 2010 Jan;32(1):34-43.
5. Peel J, John K, Page J, Jeffries O, Heffernan SM, Tallent J, Waldron M. Topical application of isolated menthol and combined menthol-capsaicin creams: Exercise tolerance, thermal perception, pain, attentional focus and thermoregulation in the heat. Eur J Sport Sci. 2023 Jun 2:1-11.
6. Hayman M, Kam PCA. Capsaicin: A review of its pharmacology and clinical applications. Trends Anaesth. Crit. Care. 2008 Oct;19(5):338-343