Smoking is a health hazard. Health Canada recommends that dried medical cannabis be consumed by inhalation using a vapourizer, rather than by smoking. Use of a vapourizer allows patients to inhale the active components of medical cannabis while avoiding by products of burning plant matter and associated carcinogens. Vapourizers work by heating the cannabis past the boiling point of the active compounds but below the point of plant matter combustion. Vapourizing cannabis is considered safer for respiratory health, and is also more cost effective.
Cannabis can be used in other ways. If you prefer, you can choose to use orally ingested oils instead of inhaling cannabis vapour, and cannabis can also be used in topical form.