Medical cannabis, while authorized by medical professionals, is still not an actual prescription. Marijuana and other forms of cannabis do not have a Drug Identification Number, meaning they are not approved by Health Canada as a prescription drug and do not have dosage recommendations. Marijuana is a drug that effects everyone differently, and with the different methods of consumption, it is difficult for a doctor to recommend any one dosage, or any one method for consuming cannabis.
One thing we do know about cannabis, is that if it contains THC (as opposed to hemp, which does not), it does impair judgement no matter how it is consumed, and can do so for up to 24 hours after the fact. Impaired judgement in safety-sensitive roles, or at any job, is a danger to the employee, their fellow employees, and the organization as a whole.
We know that any sort of impairment on the job is a safety risk, so we at CannAmm encourage all employers to know the risks involved with medically authorized marijuana:
At CannAmm, we can help you and your company mitigate the risks of medical marijuana in the workplace, and help to identify possible risks to the safety of your workers. Our Legal Cannabis Factsheet is a great resource for learning all of the risks, and includes statistics on the effects of cannabis impairment from Colorado and Washington state, where it has been legal for a couple of years.
Additionally, having medical authorization for cannabis will not grant you immunity from occupational drug testing, as the use of such a drug is proven to cause impairment, thus creating safety risks.