WASHINGTON, D.C. — Unless there is some recognized analgesic effect of rolling a joint, lighting it up and deeply inhaling the by-products of marijuana combustion, then it stands to reason that you could distill the psychoactive ingredient of marijuana, tetrahydrocannabinol, and formulate it into, say, a capsule. Doing so would combine the relief that comes with smoked marijuana with the ease of a pill and the quality control that comes with approval by the Food and Drug Administration.
Up in smoke goes the debate about medical marijuana.
Let me introduce you to dronabinol. It turns out that the miracle that is modern psychopharmacology has now shown it IS possible to render pot’s analgesic effects into capsule form. And according to a new study, it works just as well as smoked marijuana at tamping down pain. But the capsule’s effects last longer, and they come with fewer of the “abuse-related subjected effects” (i.e., feeling high) than does smoked marijuana.
For the record, dronabinol did induce some of smoked marijuana’s other side effects, some of which have medicinal value to certain populations: It did increase appetite, decrease nausea and improve sleep.
The new research appeared Monday in the Nature journal Neuropsychopharmacology. It was authored by a group from Columbia University’s College of Physicians and Surgeons.
In a small, preliminary study, researchers ran 30 subjects — all of them regular pot smokers who were in good health — through five experimental sessions. In each session, the subject would plunge his or her left hand into a vat of water set to a temperature just above freezing — 39 degrees — and hold it there for as long as was tolerable (up to two minutes), and then answer questions about the intensity of the pain or discomfort they felt.
This procedure followed the administration of one of the following: three to seven puffs of a marijuana cigarette in one of two strengths (provided by the National Institute on Drug Abuse); a single capsule containing dronabinol in one of two doses, high and low; or a placebo medication.
Each subject served as his or her own comparison group across the drug conditions. And after each dose, subjects answered questions about their “liking” for the drug administered and other subjective feelings that might suggest the degree to which the drug would inspire drug-seeking behavior.
Both marijuana and dronabinol at the higher dose increased pain tolerance and decreased pain sensitivity roughly equally in subjects. Compared with smoked marijuana, it took a bit longer for dronabinol’s analgesic effects to peak — about 180 minutes for the higher-dose THC capsule, compared with about 15 minutes for smoked marijuana. But for dronabinol, there was substantial pain relief during the period leading up to that peak; after smoked marijuana reached its peak pain-killing effect, it dropped off quickly.
Subjects declared themselves to feel less “high” on both doses of dronabinol than on marijuana.
Conclusions: marijuana in a capsule seems to fight pain, at least in a population of people who already use marijuana regularly and don’t have chronic or neuropathic pain. Its effects on populations of patients who don’t usually smoke pot, and whose pain comes from disease states such as cancer or neuropathy, still need to be tested.