Research has linked medical marijuana with a decrease in the abuse of painkillers, and now a University of Georgia study has spotlighted the potential cost savings to Medicare. For Hall County resident Katie Harrison, whose young son uses legal cannabis oil to treat seizure disorders, the report backs up her own anecdotal findings. “I’ve seen parents post their own comparison of the costs of prescription medicines they were able to wean a child off of due to cannabis use, and it’s obviously beneficial,” she said.