Medical cannabis might be a helpful therapy for some people who have chronic pain, but it’s unlikely to benefit most, according to new clinical guidelines published Wednesday in the journal BMJ.

The guidelines, crafted by an international group of researchers who analyzed three dozen medical cannabis studies, say there isn’t enough evidence that medical marijuana products help most patients suffering from chronic pain, so they shouldn’t be widely recommended for such people.

“When we look at the overall evidence for therapeutic cannabis products, the benefits are quite modest,” said lead author Jason Busse, associate director of McMaster University’s Michael G. DeGroote Centre for Medicinal Cannabis Research in Ontario.

Even as medical marijuana has been legalized in 36 U.S. states and Washington, D.C., health care providers and patients have had little guidance on when it’s appropriate to use, especially for chronic pain. Busse and his team set out to fill that gap, but found a limited pool of studies that met their criteria because of federal restrictions that make it difficult to research medical uses of cannabis.

Because of the limited data, the guidelines do not recommend the medical use of smoked or vaped marijuana. In analyzing the available research, Busse’s team found that only small percentages of participants reported “an important improvement” in chronic pain, physical function, or sleep quality while taking oral or topical cannabis treatments. [Read More @ STAT News]