Don't smoke it with tobacco: scientists suggest ways to make cannabis safer

As more countries relax their laws and with drug potency rising, it is crucial to take steps to reduce harm from cannabis use, researchers say

Scientists are calling for a major effort to make cannabis use less harmful as a rising number of countries look to replace long-standing and outright bans on the drug with more relaxed legislation.

A number of countries and US states have softened laws around cannabis use against a backdrop of rising drug potency and an apparent increase in the number of people in treatment for cannabis-related problems.