Many doctors are avoiding recommending medical marijuana to their patients, according to Boston.com. Some feel they don’t know enough about its effectiveness, or are worried about liability and lawsuits.

In Massachusetts, most doctors are not approved to certify residents as medical marijuana patients, the article notes. Patients must be certified by a doctor in order to receive legal marijuana from one of the state’s two dispensaries. Currently there are only 108 certified doctors in the state.

Prescribing medical marijuana has become a niche business for some clinics. “Those clinics are not set up to deal with a specific medical disease,” said Dr. Dennis Dimitri, President of the Massachusetts Medical Society. “They’re set up to prescribe a drug. And I cannot think of other examples of physicians who have a clinic whose only purpose is to prescribe a specific medication or drug.” He added, “I think at this point, for many physicians, they feel like the jury is still out on medical marijuana.”

Many doctors are concerned that because marijuana is banned by the federal government, their medical licenses could be at risk if they recommend it. Some hospitals and medical practices are discouraging doctors from discussing medical marijuana with their patients, according to the article. Officials at the Cambridge Health Alliance have told their providers not to certify patients “pending better evidence about the benefits and risks of marijuana,” according to spokesman David Cecere.

Patients looking for medical marijuana certification can turn to Canna Care Docs, which has eight locations in Massachusetts. Some patients are referred to the clinics by their doctor, according to Operations Manager Kathleen McKinnon. Others come on their own because their doctor does not want to discuss medical marijuana, or because the patients do not want to ask their doctor about it, she said.