Cannabis can alleviate psychiatric, physical symptoms, but results mixed, speaker says

A significant number of individuals report using cannabis to treat psychiatric and physical challenges, yet the evidence remains mixed on its efficacy, according to a presenter at the NEI Max virtual conference.

“Patients ask me to use cannabis for things that either they're currently receiving treatment for yet not getting benefit from, or they wonder if it might help them with something that may enhance or improve how they feel,” Kari L. Franson, PhD, PharmD, BCPP, professor of clinical pharmacy at University of Southern California School of Pharmacy, said during a presentation. “That all comes down to hope. We know, as clinicians, when people are coming to us and asking us for help for either of these situations, we have to recognize that and have an honest conversation on the likelihood for different disease states that cannabis is going to be beneficial.”

According to Franson, people often choose to use cannabis with tetrahydrocannabinol (THC) to help treat severe pain, muscle spasms, nausea and PTSD, and they may use it as an opioid replacement or for several other reasons. Patients may use cannabis high in cannabidiol (CBD) for what they perceive as their general well-being; specifically, it may help mitigate symptoms related to chronic pain, anxiety, depression, insomnia and seizures, Franson said.

Results of two meta-analyses showed a reduction in pain of greater than 30% among individuals who used THC-type cannabis. Several trials have also showed reductions in pain related to cancer and multiple sclerosis among those who used hybrid-type cannabis. CBD-type cannabis appeared effective at reducing pain in a case study of individuals with neurofibromatosis type 1, yet it had no effect on pain among women with fibromyalgia.

Regarding opioid use and harms, pre-clinical studies suggested cannabis use had an opioid-sparing effect, with patient self-reports having supported this finding. However, study results have shown divided results regarding opioid use among individuals with chronic pain, with some suggesting that medicinal cannabis availability may be linked to a decrease in opioid use, whereas other studies refute this finding. Franson noted that patients of a medical cannabis program in New Mexico appeared to be significantly more likely to stop all their medications. In states with laws permissive of medical cannabis use, Franson emphasized that data in 2014 to 2015 showed a decrease in opioid deaths; however, more recent data suggests a shift toward an increase in opioid deaths in these areas.

Cannabis use may also benefit individuals with PTSD, with one study showing PTSD symptom improvements among 650 veterans who used THC-type cannabis. A few randomized controlled trials showed similar improvement; however, an observational study that included more than 2,200 veterans between 1992 and 2011 found worsened PTSD symptom severity, violent behavior and alcohol and drug use related to cannabis use.

Results of a naturalist study of changes in depression, anxiety and stress symptoms from THC and CBD use according to tracking app data showed depression decreased by 50% and anxiety decreased by 58% after 20 minutes. CBD-type cannabis was linked to the largest changes in depression ratings. However, Franson noted baseline depression symptoms exacerbated across time.

Franson also highlighted the effects of cannabis use on sleep.

“A lot of people are turning to cannabis for improved short-term sleep outcomes,” Franson said. “What we see acutely with THC-type is a decrease in sleep latency, so you'll get to sleep faster, but you'll also have a decrease in REM sleep. Depriving people of REM sleep over a period of a week [has appeared linked] to psychosis.”