Cannabis temporarily relieves PTSD symptoms

June 9, 2020

Science Daily/Washington State University

People suffering from post-traumatic distress disorder report that cannabis reduces the severity of their symptoms by more than half, at least in the short term, according to a recent study led by Carrie Cuttler, a Washington State University assistant professor of psychology.

Cuttler and her colleagues analyzed data of more than 400 people who tracked changes in their PTSD symptoms before and after cannabis use with Strainprint, an app developed to help users learn what types of medical cannabis work best for their symptoms. The group collectively used the app more than 11,000 times over a 31-month period.

The study, recently published in Journal of Affective Disorders, shows cannabis reduced the severity of intrusions, returning thoughts of a traumatic event, by about 62%; flashbacks by 51%, irritability by 67%, and anxiety by 57%. The symptom reductions were not permanent, however.

"The study suggests that cannabis does reduce symptoms of PTSD acutely, but it might not have longer term beneficial effects on the underlying condition," said Cuttler. "Working with this model, it seems that cannabis will temporarily mask symptoms, acting as a bit of a band aid, but once the period of intoxication wears off, the symptoms can return."

PTSD is a disorder affecting people recovering from traumatic events and impacts women at about twice the rate as men with a 9.7% to 3.6% lifetime prevalence, respectively. While therapy is recommended as the primary treatment, Cuttler said there is growing evidence that many people with PTSD are self-medicating with cannabis.

"A lot of people with PTSD do seem to turn to cannabis, but the literature on its efficacy for managing symptoms is a little sparse," Cuttler said.

This study provides some insight into the effectiveness of cannabis on PTSD symptoms, but as the authors note, it is limited by reliance on a self-selected sample of people who self-identify as having PTSD. Also, it is not possible to compare the symptom reductions experienced by cannabis users to a control group using a placebo.

While some placebo-controlled clinical trials have been done with nabilone, a synthetic form of THC, few have examined the effects of the whole cannabis plant on PTSD.

In this study, Cuttler and her colleagues looked at a variety of variables but found no difference in the effect of cannabis with differing levels of tetrahydrocannabinol (THC) and cannabidiol (CBD), two of the most studied constituents of cannabis. The results imply that it is some combination of THC, CBD and perhaps some of the many other parts of the cannabis plant that create the therapeutic effect. Cannabis has many molecules that can create a biological effect, including up to 120 cannabinoids, 250 terpenes and around 50 flavonoids.

"We need more studies that look at whole plant cannabis because this is what people are using much more than the synthetic cannabinoids," said Cuttler. "It is difficult to do good placebo-controlled trials with whole plant cannabis, but they're still really needed."

https://www.sciencedaily.com/releases/2020/06/200609144458.htm

Cannabis may hold promise to treat PTSD but evidence lags behind use

September 3, 2019

Science Daily/University College London

As growing numbers of people are using cannabis to treat post-traumatic stress disorder (PTSD), a new UCL study reports that prescriptions are not backed up by adequate evidence.

The systematic review, published in the Journal of Dual Diagnosis, finds that the active components of cannabis, called cannabinoids, may hold promise as a treatment for PTSD, particularly for reducing nightmares and helping people sleep, but more research is needed to determine whether these drugs should be used in routine clinical practice.

"There has been a recent surge of interest in the use of cannabinoids to treat PTSD, particularly from military veterans, many of whom are already self-medicating or obtaining prescriptions in some American states," said the study's lead author, Dr Chandni Hindocha (UCL Clinical Psychopharmacology Unit).

"The lack of evidence supporting cannabis as a PTSD treatment is striking given the vast interest in it, and the large unmet need for better PTSD treatments," she said.

PTSD is a potentially debilitating condition affecting roughly 1% of the UK population, typically consisting of re-experiencing a traumatic event through intrusive memories, flashbacks or nightmares, and often involves hyper-reactivity (a state of constant vigilance) and insomnia.

Psychotherapies (talking therapies) including trauma-focussed cognitive-behavioural therapy have been shown to be effective for PTSD. However, not everyone can access talking therapies and they do not work for everyone, so many people still need to take prescribed medications. Existing drugs approved for PTSD do not work for everyone, and can have side effects, so researchers say there is an urgent need to identify new treatments.

A growing number of people have turned to cannabinoids, which is an approved treatment for PTSD in most states in the USA that permit medical cannabis.

Cannabinoids, the active ingredients of cannabis, which include tetrahydrocannabinol (THC) and cannabidiol (CBD), may be helpful at treating PTSD as they can change how the brain processes memories. The cannabinoids act on the brain's in-built endocannabinoid system which also regulates other brain functions that are affected by PTSD.

The research team conducted a systematic review of all studies where someone with a PTSD diagnosis has been using a cannabinoid to reduce their symptoms, and they assessed the quality of each study.

They found 10 studies that met their criteria, which cover a range of products including smoked cannabis, THC or CBD separately in oil or pill form, and a synthetic cannabinoid called nabilone.

Every study had medium to high risk of bias and all were assessed as low in quality due to limitations such as small sample size, retrospective study design, lack of a control group or placebo, short follow-up periods, and not reporting other medication use or addiction. Only one study was a randomised controlled trial, investigating nabilone, but it was in a small sample over a relatively short period of time.

The researchers say there are still many unanswered questions about the safety and efficacy of cannabis-based medications for PTSD, and potential long-term effects such as addiction or a risk of psychosis.

The existing evidence shows promise, however, as some studies showed that cannabis products appeared to reduce PTSD symptoms such as insomnia and nightmares.

"Based on the evidence, we cannot yet make any clinical recommendations about using cannabinoids to treat PTSD. Current prescribing of cannabinoids for PTSD is not backed up by high quality evidence, but the findings certainly highlight the need for more research, particularly long-term clinical trials," said the study's senior author, Dr Michael Bloomfield (UCL Psychiatry and the Traumatic Stress Clinic, St Pancras Hospital).

"Many of these studies have been conducted in military veterans, but we also need to be looking at other groups, as PTSD can vary depending on the nature of the trauma so different approaches may benefit different groups," he added.

Dr Hindocha added: "Unfortunately, medicinal uses of cannabis have historically been difficult to study due to legal restrictions, so it could take a long time before there is enough evidence to support clinical recommendations. New approaches are needed to make the most of existing evidence in the meantime."

The study was conducted by researchers at UCL and the University of Amsterdam, and was supported by the National Institute for Health Research UCLH Biomedical Research Centre.

https://www.sciencedaily.com/releases/2019/09/190903194249.htm