Daily Dose Q&A

2025-07-10

THC is metabolized by Cytochrome P450 enzymes, including CYP2C9 and CYP3A4. What are commonly consumed medications that inhibit these CYP enzymes?

If inhibitors of CYP2C9 (e.g. amiodarone, fluconazole) and/or inhibitors of CYP3A4 enzymes (e.g. ketoconazole, itraconazole, clarithromycin, ritonavir, erythromycin, grapefruit juice) are co-administered with a THC product, there may be an increased THC-related adverse reaction.

Prescribing Cannabis Medicines for Chronic Non-cancer Pain v2 September 2019 c10. - by the Australian Centre for Cannabinoid Clinical and research Excellence https://www.ces.edu.co/wp-content/uploads/2020/09/acre-prescribing-guidance-chronic-non-cancer-pain.pdf

2025-07-09

Should the cannabinoid dosing regimen be adjusted for a patient with renal insufficiency?

After being metabolized by the liver, cannabinoids are excreted through the GI tract and kidney. One of the key points of the European Pain Federation position paper is Consider a lower starting dose in patients with renal and hepatic insufficiency.

Huser, W, Finn, DP, Kalso, E, et al. European Pain Federation (EFIC) position paper on appropriate use of cannabis_based medicines and medical cannabis for chronic pain management. Eur J Pain.. 2018; 22: 1547Đ 1564. https://pubmed.ncbi.nlm.nih.gov/30074291/ Grotenhermen F. Clinical pharmacokinetics of cannabinoids. J Cannabis Ther, 2003; 3(1): 3-51. https://www.tandfonline.com/doi/abs/10.1300/J175v03n01_02

2025-07-08

Should the dosing regimen of cannabinoid-based products be altered for patients with hepatic insufficiency?

Cannabinoids are metabolized by the liver and excreted through the GI tract and kidney. When considering cannabinoid-based products for patients with severe liver impairment, the dosage of the cannabinoid-based products may need to be adjusted. For example, according to the prescribing information for an FDA-approved cannabidiol product, patients with hepatic impairment require dosage adjustment. A slower dose titration in patients with moderate or severe hepatic impairment than in patients without hepatic impairment is recommended.

Highlights for prescribing information for Epidiolex. https://www.accessdata.fda.gov/drugsatfda_docs/label/2018/210365lbl.pdf

2025-07-07

Compared to younger adults, are elderly patients more or less sensitive to the pharmacological effects of cannabinoids?

In general, there is a greater frequency of decreased hepatic, renal, and/or cardiac function in the elderly population compared to younger populations. Also, concomitant disease and other drug therapy is more common in the elderly population, and elderly patients typically metabolize drugs more slowly. As a result of all of these factors, elderly patients are affected by cannabinoids differently than the younger populations are affected. According to the drug monographs of cannabinoid medications approved by the Medicines and Healthcare Products Regulatory Agency in the UK, Health Canada and/or the US Food and Drug Administration, elderly patients may be more sensitive to the psychoactive and neurologic side effects of cannabinoids compared to younger adults. Also, elderly patients may be more sensitive to the hypotensive effects of cannabinoids.

FDA Product data for nabilone for oral administration https://www.accessdata.fda.gov/drugsatfda_docs/label/2006/018677s011lbl.pdf accessed 12/24/18 Hughes SG. Prescribing for the elderly patient: why do we need to exercise caution? Br J Clin Pharmacol. 1998;46(6):531-3. Lloyd SL, Striley CW. Marijuana Use Among Adults 50 Years or Older in the 21st Century. Gerontol Geriatr Med. 2018;4:2333721418781668. Published 2018 Jun 21. Valeant Canada. Cesamet Product Monograph. 2009. - https://pdf.hres.ca/dpd_pm/00007760.PDF Abbott Products Inc. Marinol product Monograph. 2010 - https://pdf.hres.ca/dpd_pm/00013378.PDF GW Pharmaceuticals. Sativex Product Monograph. 2013. - https://pdf.hres.ca/dpd_pm/00016162.PDF

2025-07-03

Are there any dosing considerations for recommending/prescribing cannabinoid-based medicines for patients utilizing high doses of opioids or benzodiazepines?

According to the European Pain Federation position paper on appropriate use of cannabis-based medicines and medical cannabis for chronic pain management, in the absence of available literature, it is the panel expert opinion that cannabis use could worsen the cognitive impairment caused by high doses of opioids and benzodiazepines. If cannabis is prescribed, it should be prescribed at a low dose and should be discontinued if it affects patients' memory, mood or function. Physicians should consider tapering high opioid (ł90 mg morphine equivalent/day) or benzodiazepine doses, especially in patients with chronic noncancer pain. A key point from that position paper is: Do not prescribe cannabis_based medicines to patients taking high doses of opioids or benzodiazepines.