Article title: Acute Cardiovascular Effects of Marijuana Use
The Review:
The authors of this systematic review combed through multiple previously published studies, looking at the short-term cardiovascular effects of THC on the body. The cardiovascular effects they covered included: changes in blood pressure, heart rate, and blood flow to the brain (cerebrovascular circulation).
This review showed that for blood pressure, the results were undecided, as some studied showed a drop in blood pressure, while others did not. For heart rate, the studies showed an increase after consuming marijuana, but quantity and duration were not mentioned. As for blood flow to the brain, only one study showed a potential decrease while the others found no change. The THC percentage of the products used (mainly inhaled ones) ranged from 1.2% to 17.5%.
Dr Caplan and the #MDTake:
This limited review aims to evaluate the effects of THC on blood pressure, heart rate and blood flow to the brain, but it has important limitations. In terms of how the changes were recorded in the studies and the relevant amounts (of what is changing) were not mentioned. For instance, while the study did show that THC may increase heart rate in the short term, it is not clear what the relevance is, what risk this may poses to consumers if any. Past literature has shown that heart muscle can respond to specific cannabinoids, both in the lab and in animals trails. Several case studies have reported individuals with grave reactions, although these concerns have yet to be replicated in a controlled manner, nor correlated with any specific circumstances or components of cannabis. Toward a goal of maximizing safety, caution is likely warranted for those consuming cannabis with known cardiac risk factors (including heart dysfunction, blood pressure concerns, rhythm abnormalities, and others) particularly with regard to the consumption of high THC products.
Clinical Impressions:
Clinically, there is a distinct trend of people who have found heart rate effects with their cannabis use, mostly increased heart rates at the beginning of use (both when first beginning to consume cannabis as well as early on during an episode of consumption.) There seems to be a tolerance to the heart rate effects because many report that this effect wanes over time. There are a clear group of patients for whom cannabis lowers blood pressure, but also groups for who it either has no effect or increases blood pressure. The long-term trend again seems that tolerance plays a role in bringing all extremes to the middle ground. Regarding blood flow, there seems to be a clear increase in local blood flow with topicals and, at least among CED Clinic patients, no observable relationship between cannabis use and blood flow, from a macroscopic perspective.
View this review (yellow link) or download:
This paper is also stored here: http://bit.ly/2MLkihz inside the CED Foundation Archive
To explore related information, click the keywords below: