SAN MATEO, Calif. (AP) - The first federally approved study to give AIDS patients marijuana to determine whether the drug can effectively control their pain is under way in northern California.

In November, the federal government authorized the use of marijuana confiscated by law enforcement to be transferred to San Mateo County Health Center for a 12-week study.

Patients will be given 15 marijuana cigarettes over a prescribed time and will be asked to keep a detailed log of their drug use, said Dr. Dennis Israelski, chief of infectious diseases and AIDS medicine at the center. The study will involve 60 AIDS patients who have pain in their limbs and who have already used marijuana.

Supporters of the study hope it will determine whether marijuana relieves pain and increases appetites as many users claim.

California voters in 1996 passed a proposition which allows possession, cultivation and use of marijuana for medicinal purposes. However, implementation of the measure has proven difficult, particularly since federal law says distribution of the drug is a crime.

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