If you are currently being treated with any of the following medications, you should not use uva ursi without first talking to your health care provider.

Drugs and supplements that make urine more acidic -- These include vitamin C, cranberry juice, orange juice, and other citrus fruits and juices.

Nonsteroidal anti-inflammatory drugs (NSAIDs) and corticosteroids -- Animal studies conducted in Japan suggest uva ursi may increase the anti-inflammatory effects of these drugs, although it isn't known whether the herb would have that effect in people.