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The Prescription Drug Problem: Addressing Issues in Safety Sensitive Workplaces

If there are 500 people in your workplace, there’s a good chance 140 of them took prescription medication before going to work. And about 10 of those people may have taken the medication for recreational purposes, NOT for medicinal reasons.

That’s the finding of a recent poll that looked at drug taking habits in the U.S. Here in Canada, the problem is also widely acknowledged. In July, the federal government announced it would invest $3.6 million to help curb prescription drug misuse and abuse. The plan includes changing the way doctors prescribe commonly abused drugs. And in a Globe and Mail article published October 6, 2014, the head of the Royal College of Physicians and Surgeons of Canada agreed the country’s doctors must do more to reduce opioid prescribing.

It’s a worrisome problem for companies that employ workers who have a valid prescription for medication but who could be compromising their own safety, the safety of their co-workers, and in some cases, endangering the public. Employers need to understand that even though a drug test may be deemed negative because there is a valid prescription, there could be underlying health and safety issues that aren’t being addressed.

Medications can be effective to treat conditions when they are used properly, but some can be addictive and dangerous when misused and abused. The chart below includes some prescribed medications that when used in ways other than as prescribed can have the potential for adverse medical effects, including addiction.


Even if they aren’t being misused or abused, some medications can have an adverse effect on those who have not built up a tolerance to the drug because they just began using it. On the other hand, just because a worker has been taking their medication properly for a long time doesn’t necessarily mean they have adapted to it. Personal sensitivity is a factor and each worker must be evaluated on their own merit. Many medications can be tolerated well but the employer needs to make sure there is a level of comfort there.

Still today, very little is taught to medical students about occupational medicine and as such, prescribing physicians may not be aware of the safety issues associated with a worker’s use of their medication. It would be helpful for the doctor to have access to the worker’s full job description, physical demands analysis, clear identification of applicable safety sensitive issues, and any other relevant documentation in order to make a value decision on whether someone should take the medication while at work. However, this is not always possible. Typically, the focus for family doctors is on treating the patient in front of them regardless of all else, including workplace related issues, which, again, may be totally foreign to them.

Employers also need to remember that the medication is being prescribed for a reason – for a health condition that needs treatment, and the health condition itself (in addition to the medication) might also create safety risks (i.e. a bus driver is taking medication for tennis elbow because he has difficulty gripping the steering wheel when it flares up).

Depending upon what an employer has included in its workplace drug testing program panel, certain prescription drug use may be flagged through a drug test, and at that point, if the laboratory reports a positive test result for a medication to the Medical Review Officer, it is a role of the Medical Review Officer to conduct a verification interview with the employee to determine if the prescription is valid and if the employee is using the medication properly. MROs can sometimes get a good feel for whether there is misuse or abuse of the medication. This is especially true in situations where the patient has been prescribed a low dose of medication but the laboratory analysis of the sample shows levels that are more compatible with a higher dose. Personal metabolism and other complicating factors must also be taken into consideration. In all cases, the MRO will ask appropriate questions to help make a determination and, where deemed appropriate and necessary, will contact the employer to alert them if there is a safety issue involved for a given worker in taking the prescribed medication. Often this issue can be fixed by having the patient talk to their family doctor about suitable alternatives the worker can take while they are on duty.

Supervisor training can also help identify indications (effectively certain signs and symptoms) that a worker might be under the influence of drugs (and/or alcohol), which in turn would lead to the triggering of reasonable cause testing. Such training is mandatory for U.S. DOT purposes, and highly recommended for non-DOT programs. The role of the supervisor in this capacity is not to diagnose nor to confirm that any specific substance has been used (unless the supervisor has directly witnessed the specific use or directly obtained such verification through disclosure by the worker), but to trigger a reasonable cause test based upon their observations of a worker’s given state that would lead the supervisor to believe that the use of a substance could be impacting the worker in some way, necessitating the need for reasonable cause testing.