marijuana and cortisol

Low-dose THC can relieve stress; more does just the opposite

Cannabis smokers often report that they use the drug to relax or relieve stress, but few studies provide clinical evidence of these effects.

Now, researchers at the University of Illinois at Chicago and the University of Chicago report that low levels tetrahydrocannabinol, or THC, the main psychoactive compound in marijuana, does reduce stress, but in a highly dose-dependent manner: very low doses lessened the jitters of a public-speaking task, while slightly higher doses — enough to produce a mild “high” — actually increased anxiety.

Cannabis is a highly regulated category 1 substance, and permits to study the drug are difficult to obtain. While it is common knowledge that many people use cannabis for its stress-relieving effects, “very few published studies have looked into the effects of THC on stress, or at the effects of different levels of THC on stress,” says Emma Childs, associate professor of psychiatry in the UIC College of Medicine and corresponding author on the study, published in the journal Drug and Alcohol Dependence.

“We found that THC at low doses reduced stress, while higher doses had the opposite effect, underscoring the importance of dose when it comes to THC and its effects.”

Childs and her colleagues recruited 42 healthy volunteers 18 to 40 years old who had some experience with cannabis use but who were not daily users.

Participants were randomly divided into three groups: The low-dose group received a capsule containing 7.5 milligrams of THC; the moderate-dose group received a capsule containing 12.5 milligrams of THC; and a placebo group received a capsule containing none. Neither the participants nor the researchers knew who was in each group.

“The doses used in the study produce effects that are equivalent to only a few puffs of a cannabis cigarette,” said Childs, noting that it is difficult to compare doses of smoked cannabis to doses of ingested THC. “We didn’t want to include a much larger dose, because we wanted to avoid potential adverse effects or cardiovascular effects that can result from higher doses of THC.”

Participants attended two four-hour sessions at the University of Chicago, five days apart. At each session, they took their capsule and then relaxed for two hours to allow the THC to be absorbed into the bloodstream.

During one session, participants were asked to spend 10 minutes preparing for a mock job interview. They were then subjected to a five-minute interview with lab assistants who did not offer any feedback, verbally or through body language, although video display was visible to the participant, showing their performance. Participants were then instructed to count backwards from a five-digit number by subtracting 13, for five minutes — a task that is “very reliably stress-inducing,” Childs said.

In their second visit, participants were asked to talk to lab assistants about a favorite book or movie for five minutes and then play solitaire for another five minutes.

Before, during and after each of the two activities, participants rated their stress levels and feelings about the tasks. Blood pressure, heart rate, and cortisol, a key stress hormone, were measured at intervals.

The participants who received 7.5 milligrams of THC reported less stress after the psychosocial test than those given a placebo, and their stress levels dissipated faster after the test.

Participants who received 12.5 milligrams of THC before the two tasks reported greater negative mood before and throughout the task, and were more likely to rate the psychosocial task as “challenging” and “threatening” beforehand. Participants who received this dose also had more pauses during the mock interview compared to those in the placebo group.

There were no significant differences in participants’ blood pressure, heart rate or cortisol levels — before, during or after the doses or the tasks.

“Our findings provide some support for the common claim that cannabis is used to reduce stress and relieve tension and anxiety,” Childs said. “At the same time, our finding that participants in the higher THC group reported small but significant increases in anxiety and negative mood throughout the test supports the idea that THC can also produce the opposite effect.”

“Studies like these — examining the effects of cannabis and its pharmacological constituents under controlled conditions — are extremely important, considering the widespread use of cannabis for both medical and non-medical purposes,” she said. “Unfortunately, significant regulatory obstacles make it extremely difficult to conduct this type of research — with the result that cannabis is now widely available for medical purposes with minimal scientific foundation.”

Low levels tetrahydrocannabinol, or THC, the main psychoactive compound in marijuana, does reduce stress, but in a highly dose-dependent manner, new research confirms.

Cannabis Addiction Is Linked to Higher Levels of Cortisol

Marijuana addicts have higher levels of “the stress hormone” cortisol.

Posted May 19, 2015


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Researchers who have been studying the impact of marijuana addiction recently reported that boys who smoke marijuana during puberty display a wide range of hormonal differences when compared to those who have never smoked the drug.

The research team, led by Dr. Syed Shakeel Raza Rizvi, found that smoking marijuana had a significant impact on levels of “the stress hormone” cortisol. The scientists found that heavy marijuana smokers have significantly higher levels of cortisol than non-smokers. That said, in terms of causation vs. correlation. it’s possible that marijuana addicts are using cannabis to self-medicate for anxiety.

Heavy Cannabis Use May Increase Stress Hormones and Stunt Growth

Rizvi hypothesizes that, “marijuana use may provoke a stress response that stimulates onset of puberty but suppresses growth rate.” Marijuana addiction appears to create a double whammy by increasing cortisol levels and decreasing growth hormone levels, which stunts growth.

According to the new study presented on May 18, 2015 at the European Congress of Endocrinology, boys who smoke marijuana go through puberty earlier than nonsmokers, but grow more slowly than those who have never smoked cannabis.

Boys who never smoked cannabis were an average of 4.6 inches taller by the age of 20 than the chronic marijuana smokers. Cannabis use in childhood could make young boys shorter for the rest of their lives. Previous studies have looked at the effect of smoking marijuana in adult rats and humans but this is the first time the effects of heavy cannabis use have been studied in pubertal boys.

The scientists at Pir Mehr Ali Shah Agriculture University Rawalpindi in Pakistan examined the levels of certain hormones involved in growth and puberty in the blood of 220 non-smoking and 217 marijuana-addicted boys. The researchers found that levels of hormones such as testosterone and luteinising hormone (LH) were increased in the marijuana smokers.

Marijuana is the most widely available illicit drug in Europe and many other countries. The latest report from the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) reveals that the highest prevalence of marijuana use is in 15-24 year olds. Statistically, cannabis use is significantly higher among males than females.

According to the Economist, Americans spend an estimated $40 billion on marijuana each year. The legal market for cannabis was estimated at $2.5 billion in 2014. A majority of Americans (52%) are now in favor of the legalization of marijuana—in 1969 that figure was just 12%. What is the potential backlash of marijuana legalization and more widespread availability of cannabis on child development?

Conclusion: Excessive Use of Any Drug Has Negative Side Effects

As with any drug, heavy cannabis use and addiction take a heavy toll on your body, brain, and mind. The researchers of this recent study believe their findings may have a wider impact beyond just cannabis use during childhood development.

Early puberty is also associated with drinking and smoking—which are currently the most potentially deadly legal habits—at a younger age. Dr. Rizvi cautions, “if children mature earlier, they may have increased risk of substance abuse because they enter the risk period at an early level of emotional maturity.”

As the father of a 7-year-old, I’m on a mission to educate myself on the most effective ways to dissuade children from abusing drugs and becoming addicts. This is a work in progress.

Personally, I strongly identify with Madonna’s upcoming single, Devil Pray. As a mother to four children, Madonna has written an insightful “anti-drug” anthem without any of the moral judgement or self-righteousness of Nancy Reagan’s “Just Say No” public service announcements of decades past. If you have a chance, check out Devil Pray here.

Hopefully, my Psychology Today blog posts on substance abuse and addiction will help people from all walks of life maintain a moderate and healthy balance when consuming any type of recreational drug such as caffeine, alcohol, or cannabis.

As someone who has lost loved ones to drug addiction, I’m on a crusade to instill a “healthy fear” of highly addictive substances such as: nicotine, heroin, and crystal meth. These three drugs can hijack your brain and steal your life.

If you’d like to read more on this topic, check out my Psychology Today blog posts:

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Heavy marijuana use may trigger a stress response that increases cortisol levels.