Source:  Nicole Bootsman, Pharmacist Manager, Prescription Review Program, CPSS

Physicians should be aware that the Prescription Review Program monitors prescribing of a list of “PRP medications” as outlined in CPSS Bylaw 26.1.

Why monitor these medications?

While it is likely intuitive that opioids, benzodiazepines, stimulants and anabolic steroids are monitored medications, you may question some of the others.  Here’s why:

• Baclofen (skeletal muscle relaxant): Misuse is often because of the drug’s sedating properties. Overdoses tend to be associated with morbidity and mortality.
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• Diphenoxylate (antidiarrheal): Listed on the federal Controlled Drugs and Substances Act (Schedule I).
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• Gabapentin/pregabalin (anticonvulsant, analgesic): May cause euphoric highs (especially at high doses) which can potentiate possible misuse. GABA analogs are active at receptor sites associated with drugs of misuse.
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• Lemborexant (hypnotic): May produce similar responses on positive subjective measures (drug liking, overall drug liking, take drug again, good drug effects) as zolpidem.
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• Ketamine (general anesthetic): Long-term use can cause dependence and tolerance with psychosis. One dose of ketamine reportedly sells for $25 in Saskatoon. Listed on the Controlled Drugs and Substances Act (Schedule I).
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• Oxybutynin (anticholinergic, antispasmodic): With its lipophilic structure, it crosses the blood-brain barrier and can cause desired hallucinogenic and anticholinergic-antimuscarinic effects. It is used to overcome depression, social anxiety and to reduce withdrawal symptoms of other substances. Selling at $5 per tablet, oxybutynin has become a source of revenue in some cases.
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• Tapentadol (analgesic): Listed on the federal Controlled Drugs and Substances Act (Schedule I).
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• Tramadol (analgesic): Listed on the federal Controlled Drugs and Substances Act (Schedule I).
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• Zolpidem (hypnotic): Similar side-effect profile to benzodiazepines. Recommended for short-term therapy only. Listed on the federal Controlled Drugs and Substances Act (Schedule IV).
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• Zopiclone (hypnotic): Similar side-effect profile to benzodiazepines, including the possibility of profound sedation and respiratory depression, and while there may be less risk of abuse, the potential for addiction still exists. Recommended for short-term therapy only.

If you have any questions regarding these medications, please contact the Prescription Review Program at prp@cps.sk.ca.

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Lemborexant (^PrDayvigo™). [cited 2021 Mar 24]. Eisai R&D Management Co., Ltd. Available from: https://pdf.hres.ca/dpd_pm/00058592.PDF. 

Janssen Inc. RxTx, 2019.

Kardas O, Burcu K. The oxybutynin abuse in adolescent case. Sanamed, 2019; 14(1): 91-94.

Cousins C. Oxybutynin Misuse: Clinical Short Snapper. medSask, 2018. Available from: medsask.usask.ca/documents/mednews-docs/36.6.1%20Oxybutynin%20Misuse_Clinical%20Short%20Snapper.pdf

Wolters Kluwer Clinical Drug Information, Inc., Lexicomp, 2019.

Centre for Addiction and Mental Health: Anti-anxiety Medications (Benzodiazepines), 2019 CAMH.

https://www.camh.ca/en/health-info/mental-illness-and-addiction-index/anti-anxiety-medications-benzodiazepines