Medical marijuana reduces the number of prescriptions written by doctors, according to a recent study published in Health Affairs. The researchers at the University of Georgia in Athens looked at all prescriptions filled by Medicare participants over a four year period for nine conditions for which medical marijuana is used for. These included anxiety, depression, glaucoma, nausea, pain, psychosis, seizures, sleep disorders and spasticity. They compared 17 states and Washington, DC where medical marijuana was legalized with those where it was not. In states with legalized medical marijuana the number of prescriptions dropped by 0.5% providing estimated savings of $165 million a year. Of all approved indications, relief of pain was by far the most common reason medical marijuana was prescribed for. This was a much more dramatic effect than the researchers anticipated. They expected that the mostly elderly patients on Medicare would be more resistant to the idea of using marijuana than younger people.
In a February post I mentioned that I started prescribing medical marijuana to my patients with migraine headaches who also have neuropathic pain as part of their headache. While medical marijuana is not approved for migraines per se, it is approved for neuropathic (i.e nerve-related pain), which many migraine sufferers do have. Burning or stabbing pain indicates the presence of neuropathic pain. So far, I’ve prescribed medical marijuana to about two dozen patients and as expected, the results are mixed. It works well for some, but not other. Most commonly, patients who’ve had positive experience with recreational marijuana tend to request medical marijuana and they tend to do better than those who’ve never tried it.
Research on medical marijuana is complicated by the fact that there is no standard formulation, which means that there is wide variation in the strains of the plant with varying amounts of active and inactive ingredients. In New York State medical marijuana can be ingested, inhaled through a vaporizer or placed under the tongue. We also have various ratios of tetrahydrocannabinol (THC) and cannabidiol (CBD), which produce different results. Nevertheless, we do plan to do an observational study of 100 migraine sufferers who also have neuropathic pain. We hope to get an indication as to what route of administration and what THC/CBD ratio work best for migraine patients.
