ST. PAUL (AP) — A new survey shows many doctors in Minnesota are reluctant to accept medical marijuana as a treatment option.

The survey was released Tuesday to the state’s Task Force on Medical Cannabis Therapeutic Research. It was conducted by task force member Dr. Charles Reznikoff, an addiction specialist at Hennepin County Medical Center.

Reznikoff sought opinions on medical marijuana from 262 doctors from four institutions across Minnesota. The majority of doctors said the qualifying conditions need to be clearer.

Many doctors said they don’t want to be burdened by the program, for which sales of medical marijuana pills, oils and vapors began in July. They also said are nervous about registering patients and worry about it at a time when so many people are abusing opioids.

“There is a lot of worry about the opioid thing,” Reznikoff said.

The agency added intractable pain late last year to the nine other qualifying conditions, but sales won’t start until August.

The survey found that doctors’ opinions about marijuana might be stopping them from certifying patients to use the drug, while other physicians said they’re not ready for challenging conversations and disputes that might cause patients to leave.

A lack of education could be the reason some doctors aren’t on board with medical marijuana, the survey found. Reznikoff said there have been only a few educational events aimed at health care providers.

“There is no ethical obligation for a provider to, on their own, adopt this,” Reznikoff said. “This isn’t aspirin for heart attacks.”

The Minnesota Department of Health said 479 practitioners are registered and authorized to certify patients to buy medical marijuana, and there are 844 patients approved to get the drug. The task force was appointed to study Minnesota’s medical marijuana program, and is preparing a report on research findings for the state Legislature this year.