Ask the Doctors

Dear Doctor: I've suffered joint pain for years. Being prescribed 15 milligrams of meloxicam has been wonderful. What are your thoughts on meloxicam use?

Dear Reader: Meloxicam (Mobic) is a non-steroidal anti-inflammatory drug (NSAID) that, like all such drugs, inhibits the formation of the enzyme cyclooxygenase (COX). This inhibition leads to a decrease in the production of molecules that boost inflammation and help the blood clot.

There are two forms of the COX enzyme, aptly named COX-1 and COX-2. COX-1 is involved in protecting the lining of the stomach, promoting the blood's clotting ability and aiding kidney function. COX-2 is involved in the inflammatory response in the body. Many of the side effects seen with older NSAIDs such as ibuprofen, naproxen and diclofenac are related to the inhibition of COX-1. The side effects include gastritis or gastric ulcers, blood thinning and kidney damage. Inhibiting COX-2 leads to a decrease in inflammation and a decrease in pain.

Meloxicam at low doses (7.5 milligrams) inhibits COX-2 and not COX-1. That means it can reduce pain and inflammation without irritation of the stomach lining or an increased risk of stomach ulcers. Research has found that serious upper gastrointestinal events at the 7.5 mg dose occur in fewer than 1 in 3,000 people. But note that follow-up studies didn't last more than 60 days, so it's unclear if these rates would hold up over the long term.

Further, at low doses, meloxicam may not trigger the kidney problems that other NSAIDs cause. The rates of heart attacks appear comparable to those of other NSAIDs, with a slight increase in risk at all doses.

However, when meloxicam dosage is increased to 15 mg, the medication does inhibit COX-1, leading to a significant increase in the rates of serious upper gastrointestinal events.

One study found that, while the number of events was less than with the NSAID naproxen, the number of events at 15 mg was six times higher than the lower dose of meloxicam (1 in 500 people). Another study showed a greater proportion of people taking 22.5 mg of the drug for 12 weeks had a slight decrease in kidney function. This was not seen at the 15 mg dosage.

Lastly, for people on two types of blood pressure drugs -- ACE-inhibitors and angiotensin receptor blockers -- meloxicam (like other NSAIDs) may make those medications less effective.

In summary, meloxicam works well for pain and swelling. The higher doses do decrease pain more than the 7.5 mg dosage, and the medication is comparable to the NSAID diclofenac for both pain relief and decreasing inflammation. I have frequently recommended the medication for joint inflammation, bone bruises and pain from fractures and tendonitis, and it's worked well for the majority of my patients. For older adults, I lean toward the 7.5 mg dose, but I have recommended 15 mg in more severe cases. Some of the latter group have complained of gastrointestinal discomfort, but this stopped when they discontinued the medication. I rarely give this medication for greater than one month, but have had some patients with severe arthritis who have been on this medication for years.

I don't know how frequently you are using meloxicam, but if you're using it on an as-needed basis, it should be safe. If you're using this medication daily, you should consider its potential for side effects.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

More like Ask the Doctors