Under Georgia's 2015 law, patients and, in the case of children, families who register with the state are allowed to possess up to 20 ounces of cannabis oil to treat severe forms of eight specific illnesses, including cancer, Parkinson's disease and epilepsy.

The oil can have no more than 5 percent THC, the component in the drug that makes people high.

The House vote comes two weeks after the state Senate passed a medical marijuana measure that would add autism to the list of eligible conditions, but also reduce the allowable maximum THC level in the oil to 3 percent — a mandate unpopular with many of the law's advocates.

Senators wanting to reduce the maximum THC level say the move would bring the state more in line with others that also allow limited forms of the oil. Federal officials continue to classify the oil as an illegal drug.