People with arthritis are more likely than others to be using herbal remedies, and this increases the chances of serious interactions with prescribed medications, a British study shows.

Echinacea, gingko biloba, devil’s claw, ginger and garlic are the most dangerous, Dr. Wendy Holden told Reuters Health.

Echinacea poses a risk of liver damage when used with the more potent anti-arthritis medications known as ‘disease modifying antirheumatic drugs.’

The other herbal remedies could aggravate stomach bleeding risks when taken along with nonsteroidal anti-inflammatory drugs such as ibuprofen, or with steroids.

To examine the extent of the problem, Holden, at Nuffield Orthopaedic Centre in Oxford, and her colleagues sent anonymous questionnaires to 238 patients being treated by rheumatologists.

A total of 105 subjects (44 percent) had used herbal or over-the-counter remedies in the previous 6 months, the authors report in the Annals of the Rheumatic Diseases.

“This is much higher than the general population,” Holden told Reuters Health. “These patients have a condition that will last for life, and they’re keen to seek alternatives rather than conventional medications sometimes.”

Twenty-six subjects (11 percent) were taking remedies that put them at risk for serious interactions with conventional drugs. Their responses showed that almost all of them were unaware of the risk, although ten of them had sought advice from a health professional before starting.

“Physicians have to be super cautious to make sure they ask what medications the patients are taking,” Holden advised. “And patients should be asking their doctors - if they’re already on herbal remedies - if they’re safe to take with arthritis drugs.”

SOURCE: Annals of the Rheumatic Diseases, May 2005.