A new study of medical cannabis patients finds considerable variability in product choice – even among those with the same condition – suggesting a lack of consistent clinical guidance.
Until now, understanding what products medical cannabis patients use for various conditions has mostly come from survey responses due to a lack of publicly available data.
In a new study, USC Schaeffer Center researchers have established a clearer picture by analysing point-of-sale data from nearly 17,000 patients who made more than 80,000 purchases as part of the New York state medical cannabis programme.
The researchers found considerable variation in the products chosen for most medical conditions and high variability in labelled doses of THC.
“While the medical cannabis market is not new, there is still relatively little research on patient purchasing behaviour,” says Alexandra Kritikos, a postdoctoral research fellow at the USC Schaeffer Center and the USC Institute for Addiction Science.
“Unfortunately, our analysis suggests that patients may not be getting consistent guidance from clinicians and pharmacists and, in many disease areas, there seems to be a lack of clear clinical data on appropriate dosing.”
The results, published in JAMA Network Open, rely on purchases made between 2016 and 2019 when cannabis flower and edibles could not be sold in the medical market. Cannabis cardholders could purchase vape cartridges and pens, capsules and tablets, tinctures, lotions and suppositories.
Medical cannabis patients purchase a range of products with varying potencies
Since its inception in 2014, New York’s medical cannabis programme has grown to 150,000 participants, making it one of the largest in the US.
Using data from an integrated single system of dispensaries, the researchers found that the top three conditions patients recorded on their medical card were chronic pain (52 per cent), neuropathy (22 per cent) and cancer (13 per cent). In addition to a qualifying condition, patients also needed a qualifying symptom to register. The top qualifying symptoms were severe pain (82 per cent), severe muscle spasms (21 per cent) and severe nausea (8 per cent).
Vaporisers were the most popular product purchased (40 per cent), followed by tinctures (38 per cent) and tablets (22 per cent).
In terms of potency, the majority of products purchased (52 per cent) were high-THC, low-CBD products. High-THC products contained between 2 and 10 mg of THC per dose, depending on the product.
The data showed that patients favoured different dosing and methods of administration depending on their condition. For example, 41 per cent of patients with chronic pain preferred a high-THC vaporiser, which delivered 2 mg of THC/0.1 mg of CBD per dose, while 33 per cent of chronic pain patients chose tinctures and 25 per cent chose tablets, both of which delivered 10 mg of THC per dose. Another quarter of chronic pain patients chose a product containing 5 mg of both THC and CBD.
In contrast, the majority of patients suffering from cancer, HIV/AIDS and epilepsy purchased the same product, suggesting similar dosing.
Physicians need to take a more active role, researchers say
Earlier research found that electronic medical records frequently underreport the number of medical cannabis users. Combined with findings in the new Schaeffer Center study, the researchers suggest improving medical guidance and oversight of dosing.
Rosalie Liccardo Pacula, senior author on both studies, commented: “We suspect the lack of clinical guidelines on dosing of cannabinoids for particular medical conditions has made medical providers uncomfortable talking to their patients about their medical cannabis use.
“It is imperative that this change, as drug interactions with other prescribed medications are likely but impossible to identify if medical cannabis use is not considered or recorded in the medical record.”
Pacula and Kritikos hope that their study provides a basis for conversations between providers and patients about cannabis use, including dosing levels.
Calls for caps in the recreational market will not limit access for medical cannabis patients
According to the labelled dosing, none of the most popular products analysed for any of the conditions had dosing of more than 10 mg of THC, something policymakers should consider, say the researchers.
“We’ve seen the industry and media make the claim that putting caps on potency would limit access to necessary medicine,” Pacula says.
“But our research in New York state suggests that medical cannabis users are consuming products that are less potent than what recreational users take.”