Metered-Dose Inhalers for Medical Cannabis Use

Limited evidence of the clinical effectiveness of metered-dose inhalers for medical cannabis is available from patients who were prior users of medical cannabis (primarily by smoking) for treating chronic pain, chemotherapy-induced nausea, or spasticity. No evidence was found for using metered-dose inhalers for medical cannabis in patients who were naive to medical cannabis. Inhalation of medical cannabis using a metered-dose inhaler delivers low and precise doses of delta-9-tetrahydrocannabinol that provide a rapid onset of action and dose-dependent effects and is generally well tolerated. No consistent or prolonged cognitive impairment occurred following inhalation of medical cannabis using a metered-dose inhaler in patients who had previously used medical cannabis for their medical condition. No evidence was found that directly compared inhalation of medical cannabis using a metered-dose inhaler versus consumption of medical cannabis by an alternate route such as smoking, vapourizing, vaping, dabbing, mucosal administration, or oral ingestion. No evidence-based guidelines were identified for using metered-dose inhalers for medical cannabis to inform best practices.