VANCOUVER—A government prohibition against mixing cannabis and caffeine makes little sense, say some research scientists. There is only speculation that the combination might pose a risk.

The practice, so common in the legendary pot capital of Amsterdam that cannabis dispensaries are called “coffee shops,” appears unlikely to be coming to Canada anytime soon.

“It seems like the overriding philosophy for a lot of this is: ban anything that might be a concern,” said M-J Milloy, research scientist with the B.C. Centre on Substance Use. “Then it’s easier to un-ban … rather than trying to do it the other way around.”

Milloy said while both caffeine and cannabis have been known cause tachycardia (an abnormally fast heart-rate), he hadn’t heard of any adverse effects coming from combining the two.

Milloy speculated banning caffeine and cannabis could mean the government wishes to avoid commercial production of highly-caffeinated energy drinks laced with THC, the psychoactive compound found in cannabis.