UK prescribed medical cannabis is typically vaporised, not smoked, to avoid...

https://iris-wiki.win/index.php/Why_Are_Conduction_Vapes_Cheaper_Than_Convection_Vapes%3F

UK prescribed medical cannabis is typically vaporised, not smoked, to avoid harmful toxins from combustion. Vaporiser type—conduction or convection—and temperature settings influence the release and effects of cannabinoids