How well do they work?

Opinions differ on the effectiveness of over-the-counter topical pain medications. While many people say these products help relieve their arthritis pain, scientific research reveals only modest benefits. Some products work no better than placebo in relieving arthritis pain. Salicylates appear to be more effective for muscle aches, while capsaicin products are more often used for pain associated with damaged nerves — such as postherpetic neuralgia.

Are they safe to use?

Application of capsaicin creams can make your skin burn or sting, but this discomfort generally lessens within a few weeks of daily use. Wash your hands thoroughly after each application and avoid touching your eyes and mucous membranes. You may need to wear latex gloves when applying the cream.

If you are allergic to aspirin or are taking blood thinners, check with your doctor before using topical medications that contain salicylates. Don't use topical pain relievers on broken or irritated skin or in combination with a heating pad or bandage.

Are there topical pain products available by prescription?

Pills containing nonsteroidal anti-inflammatory drugs (NSAIDs) are a common treatment for osteoarthritis, but they can irritate the stomach. In Europe, many doctors prescribe NSAID creams or gels because they have a lower risk of stomach irritation. Some studies indicate that many NSAID creams and gels work as well as their oral counterparts.

In the United States, the Food and Drug Administration has approved several topical products (Voltaren, Pennsaid, others) that contain the prescription NSAID diclofenac for the treatment of osteoarthritis in joints close to the skin's surface, such as the hands and knees.

In some cases, doctors may prescribe patches containing a numbing medication, such as lidocaine (Lidoderm), for joint pain. The patches are approved in the U.S. to treat a painful complication of shingles, but they may be used for other types of pain — what is called an off-label use. Patches are placed on your skin over the painful joint for 12 hours at a time.

Aug. 01, 2013 See more In-depth