Despite a need for more robust evidence, many patients with chronic pain are being treated with medical cannabis and cannabinoids. In the Journal of Cannabis Research, the Global Task Force on Dosing and Administration of Medical Cannabis in Chronic Pain—which included 20 global experts from 9 countries—published consensus-based recommendations on how to dose and administer medical cannabis for chronic pain using a modified Delphi process.
“Currently, there is reluctance among clinicians to prescribe medical cannabis for chronic pain because there are no accepted guidelines on dosing and administration of this therapy,” says Task Force Member Alan Bell, MD. “The goal of our consensus recommendations is to provide direction on dosing and administering medical cannabis to give clinicians one more tool in their toolbox to treat chronic pain. These are important recommendations because medical cannabis is an alternative to opioids, which are associated with high potency but also high toxicity.”
Key Medical Cannabis Recommendations
Per the recommendations, there was consensus for considering medical cannabis in patients with neuropathic, inflammatory, neoplastic, and mixed pain. Chronic pain can be treated with medical cannabis following one of three protocols based on patient characteristics—routine, conservative, or rapid—and patients can be moved across protocols to help tailor approaches. Using oral formulations, the Task Force recommends starting with cannabidiol (CBD) in most cases, because many patients benefit solely from CBD. Unlike tetrahydrocannabinol (THC), CBD does not have psychoactive properties.
The majority of patients can be treated using a routing protocol, in which patients are started on 5 mg of CBD twice daily and titrated by 10 mg every 2-3 days until they reach their goals, or up to 40 mg/day. THC should only be added if patients fail to respond to CBD. Starting with 2.5 mg daily, THC may be titrated by 2.5 mg every 2-7 days. THC should be capped at 40 mg daily (Figure).
A conservative protocol should be used when managing frail and elderly patients with chronic pain and for those with severe comorbidities or polypharmacy. With this protocol, CBD is initiated at a dose of 5 mg once daily and titrated by 10 mg every 2-3 days until patients reach their goals, or up to 40 mg/day. At a CBD dose of 40 mg/day, clinicians may consider adding THC at 1 mg/day and titrating by 1 mg every 7 days until a maximum daily dose of 40 mg/day of THC is reached.
Patients with severe pain, cancer, and those with significant prior cannabis use can follow the rapid protocol, in which a CBD-THC balanced dose is initiated between 2.5 and 5 mg of each cannabinoid once or twice daily. The dose can be titrated by 2.5-5 mg of each cannabinoid every 2-3 days until patients reach their goals or to a maximum THC dose of 40 mg/day.
A Clear Pathway to Initiate Medical Cannabis into Practice
The consensus recommendations are flexible because chronic pain treatment is not one-size-fits-all, says Dr. Bell. “Cannabis-naïve patients are very different than patients who have used cannabis for decades, and patients with advanced cancer have different needs than those with non-cancer-related pain,” he adds. “We developed algorithms to guide treatment based on individual patient characteristics. With our recommendations, there is a clear pathway to initiate appropriate dosing and administration of medical cannabis into your practice tomorrow.”
Dr. Bell notes that the recommendations take a safety-minded, conservative approach because research is lacking on medical cannabis for chronic pain. “Clinicians may be skeptical about medical cannabis, but our options for treating chronic pain are limited,” he says. “We advocate using a ‘start low, go slow’ approach for dosing and titration. The goal is to find the sweet spot of reducing pain symptoms while minimizing, and often avoiding, euphoric effects.”
Medical Cannabis Studies Sorely Needed
The recommendations will be updated as new data emerge on the dosing and mode of administration of medical cannabis for chronic pain. “Randomized control trials are sorely needed to compare safety and efficacy of medical cannabis against current standards of care for chronic pain,” says Dr. Bell. “We also need studies that explore the degree of pain reduction in patients treated with CBD-based therapies.”