After six months of treatment, more than 93 percent of respondents reported their pain dropped from a median of eight to four on a 10-point pain scale. Nearly 60 percent who originally reported "bad" or "very bad" quality of life said their lives had improved to "good" or "very good." And over 70 percent reported moderate to significant improvement in their medical condition.

About a third of the patients used cannabis-infused oil, about 24 percent smoked marijuana, and about six percent used a vaporizer. The most common side effects from cannabis use were dizziness and dry mouth, researchers reported in The European Journal of Internal Medicine .

"We found medical cannabis treatment significantly relieves pain and improves quality of life for seniors with minimal side effects reported," said Victor Novack, MD, a professor of medicine at BGU and head of the Soroka Cannabis Clinical Research Institute.