Patients with advanced cancer who take strong pain medicines like morphine or oxycodone throughout the day can feel like they are in a fog most of the time.

But according to a report in the Journal of Clinical Oncology (Vol. 20, No. 1: 335-339), Ritalin can help clear away the fog. Ritalin is a brain stimulant, most often used for children with attention deficit disorder. It has replaced the drug Dexedrine because it is not as readily abused.

In the study, Mark H. Rozans, MD, and his colleagues from Tulane Medical School, reviewed several studies of Ritalin in cancer patients. The patients had been treated with narcotics for their cancer pain.

All of the studies found that patients were less sleepy on Ritalin. In addition, there was a suggestion that the Ritalin might also make the patients less sensitive to their pain.

Ritalin helped patients in other ways, too. For example, depression is another problem in cancer patients. Although drugs like Prozac can help, they take a long time to work. Ritalin is immediately effective, the authors said.

The authors reviewed several studies that found that Ritalin could reverse depression in advanced cancer patients. The studies showed that about 80% percent of patients were helped by the drug.

Another benefit of Ritalin was that it helped patients think more clearly. Because cancer patients take many drugs and are often weak they may not feel as "sharp" as they would like to be. Patients on the drug communicated better with their loved ones and appreciated the world around them, the authors said.

What about side effects? Ritalin can cause fast heartbeat, high blood pressure, insomnia (trouble sleeping), and nervousness in many patients. But in the studies the doctors reviewed, this did not seem to be much of a problem.

The drug hasn’t been studied well enough in many patients and this concerned Rozan and his colleagues. They recommended that more clinical trials be done to test Ritalin’s effectiveness in advanced cancer patients.

Even though there have been few clinical trials, the authors found Ritalin to be an effective and well-tolerated drug that can be used in patients with advanced cancer to improve mental functioning. The authors cautioned that it be given early in the day so as not to interfere with sleep.