Catherine J Lucas1, Peter Galettis2, Shuzhen Song3, Nadia Solowij4, Stephanie E Reuter5, Jennifer Schneider6, Jennifer H Martin2. 1. Discipline of Clinical Pharmacology, School of Medicine and Public Health, University of Newcastle, Newcastle, New South Wales, Australia. Electronic address: catherine.lucas@newcastle.edu.au. 2. Discipline of Clinical Pharmacology, School of Medicine and Public Health, University of Newcastle, Newcastle, New South Wales, Australia. 3. Drug/Trace Metal Lab, Chemistry Department, Pathology North Hunter, New South Wales, Australia. 4. School of Psychology and Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, New South Wales, Australia. 5. Discipline of Clinical Pharmacology, School of Medicine and Public Health, University of Newcastle, Newcastle, New South Wales, Australia; School of Pharmacy and Medical Sciences and Sansom Institute for Health Research, University of South Australia, Adelaide, South Australia, Australia. 6. School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, New South Wales, Australia.
Abstract
BACKGROUND: Medicinal cannabis is prescribed under the provision of a controlled drug in the Australian Poisons Standard. However, multiple laws must be navigated in order for patients to obtain access and imported products can be expensive. Dose-response information for both efficacy and toxicity pertaining to medicinal cannabis is lacking. The pharmacokinetic properties of cannabis administered by traditional routes has been described but to date, there is no literature on the pharmacokinetic properties of an intraperitoneal cannabinoid emulsion. CASE DESCRIPTION: A cachectic 56-year-old female with stage IV ovarian cancer and peritoneal metastases presented to hospital with fevers, abdominal distension and severe pain, vomiting, anorexia, dehydration and confusion. The patient reported receiving an intraperitoneal injection, purported to contain 12g of mixed cannabinoid (administered by a deregistered medical practitioner) two days prior to presentation. Additionally, cannabis oil oral capsules were administered in the hours prior to hospital admission. RESULTS: THC concentrations were consistent with the clinical state but not with the known pharmacokinetic properties of cannabis nor of intraperitoneal absorption. THC concentrations at the time of presentation were predicted to be ~60ng/mL. Evidence suggests that blood THC concentrations >5ng/mL are associated with substantial cognitive and psychomotor impairment. The predicted time for concentrations to drop <5ng/mL was 49days after administration. DISCUSSION: The unusual pharmacokinetic properties of the case suggest that there is a large amount unknown about cannabis pharmacokinetic properties. The pharmacokinetic properties of a large amount of a lipid soluble compound given intraperitoneally gave insights into the absorption and distribution of cannabinoids, particularly in the setting of metastatic malignancy.
BACKGROUND: Medicinal cannabis is prescribed under the provision of a controlled drug in the Australian Poisons Standard. However, multiple laws must be navigated in order for patients to obtain access and imported products can be expensive. Dose-response information for both efficacy and toxicity pertaining to medicinal cannabis is lacking. The pharmacokinetic properties of cannabis administered by traditional routes has been described but to date, there is no literature on the pharmacokinetic properties of an intraperitoneal cannabinoid emulsion. CASE DESCRIPTION: A cachectic 56-year-old female with stage IV ovarian cancer and peritoneal metastases presented to hospital with fevers, abdominal distension and severe pain, vomiting, anorexia, dehydration and confusion. The patient reported receiving an intraperitoneal injection, purported to contain 12g of mixed cannabinoid (administered by a deregistered medical practitioner) two days prior to presentation. Additionally, cannabis oil oral capsules were administered in the hours prior to hospital admission. RESULTS:THC concentrations were consistent with the clinical state but not with the known pharmacokinetic properties of cannabis nor of intraperitoneal absorption. THC concentrations at the time of presentation were predicted to be ~60ng/mL. Evidence suggests that blood THC concentrations >5ng/mL are associated with substantial cognitive and psychomotor impairment. The predicted time for concentrations to drop <5ng/mL was 49days after administration. DISCUSSION: The unusual pharmacokinetic properties of the case suggest that there is a large amount unknown about cannabis pharmacokinetic properties. The pharmacokinetic properties of a large amount of a lipid soluble compound given intraperitoneally gave insights into the absorption and distribution of cannabinoids, particularly in the setting of metastatic malignancy.
Authors: Laura M Dryburgh; Nanthi S Bolan; Christopher P L Grof; Peter Galettis; Jennifer Schneider; Catherine J Lucas; Jennifer H Martin Journal: Br J Clin Pharmacol Date: 2018-08-01 Impact factor: 4.335
Authors: Randi Melissa Schuster; Kevin Potter; Ryan Vandrey; Maya Hareli; Jodi Gilman; David Schoenfeld; A Eden Evins Journal: J Psychopharmacol Date: 2019-09-19 Impact factor: 4.153