Marijuana is the most frequently used illicit drug in the United States. Federal data published in 2018 show that approximately 15% of 12-17-year-olds have used marijuana at least once in their lifetime, a percentage that has dropped since marijuana legalization and decriminalization. Nearly 50% of adults report having used marijuana at least once in their life.
The rate of marijuana dependence in American is somewhat higher than it is globally, with an estimated 0.6% of American adults meeting criteria for a marijuana use disorder, compared to 0.19% globally. Marijuana dependence is characterized by mild physical and psychological symptoms including appetite changes, restlessness, and insomnia that become apparent when someone reduces or stops the use of marijuana. These symptoms usually resolve within a few days.
Comprehensive, scientifically valid arguments exist for the medicinal benefits of marijuana, although molecular and translational research is significantly hampered by onerous federal regulations that essentially prevent basic research on marijuana. Social and epidemiological research, on the other hand, is able to be pursued because researchers are evaluating how people who already use marijuana are affected. This is an important distinction and has substantially limited a scientifically valid understanding of molecular and cellular mechanisms of marijuana use.
How Does Marijuana Tolerance Work?
Social science has proven that frequent marijuana use is associated with the development of tolerance. However, unlike alcohol and many prescription drugs (notably opioids and benzodiazepines), marijuana tolerance and dependence are generally easily manageable and rapidly subside with short periods of abstinence and are associated with far less risk of devastating social and health consequences.
Overwhelming evidence supports that the current federal efforts made to keep marijuana illegal while turning a blind eye to the astonishing damage caused by alcohol, nicotine and prescription drugs are far more harmful to the public than an evidence-based approach to drug policy. Marijuana is similarly as addictive as caffeine and is far less toxic than alcohol and nicotine.
Causes of Marijuana Tolerance
When it comes to drug use, tolerance has a very specific definition. According to the National Institute on Drug Abuse, tolerance occurs when someone “no longer responds to the drug in the way that person initially responded.” In other words, with regular drug use someone will need to continue to increase the dose of the drug they take in order to achieve the desired effect.
The active ingredient in marijuana is delta-9-tetrahydrocannabinol (THC), and recent studies have provided substantial evidence that THC is responsible for the development of tolerance to marijuana. For example, an interesting study on the physical basis of marijuana tolerance and dependence was recently carried out by studying the brains of men who had used high doses of marijuana daily for several years.
30 adult men who were heavy, chronic marijuana users agreed to remain in an inpatient research unit for four weeks, where they were unable to use marijuana. The men had two brain scans, one at intake and the second at the end of the four weeks. The brain scans they had been called “positron emission tomography” (PET) scans, which use radioactive labeling to quantify specific chemical receptors. In this case, the researchers were looking at a receptor called cannabinoid receptor type 1 (CB1), which is the most well-characterized marijuana/THC receptor.
The researchers found that at the time of the first PET scan, the CB1 density in the brain was lower than the density in men who did not smoke marijuana, but at the time of the second scan, after four weeks of marijuana abstinence, the CB1 receptor density in marijuana smokers was back to normal levels. These findings strongly suggest that regular marijuana use results in inactivation of CB1 receptors in the brain and thus may create a tolerance to marijuana with extended or chronic use.
An overview of the key factors in tolerance development includes:
- Dosage: Higher doses of THC will cause more rapid tolerance development.
- Frequency of use: More frequent marijuana use is associated with greater tolerance.
- Duration of use: Longer periods of regular marijuana use are linked to increased tolerance.
- Interactions with other drugs: Federal restrictions continue to place onerous restrictions on marijuana research, so empirical data on marijuana interactions with other drugs remains poorly understood. However, the Department of Health has indicated that marijuana can enhance the effects of alcohol, barbiturates, and benzodiazepines (although, interestingly, it does not seem to affect opioids). Whether other drugs increase the development of marijuana tolerance remains unclear.
- Other factors: Several factors affect the development of drug tolerance, including genetics, age, metabolic state, physical and mental health and whether or not other drugs are used concurrently. How these factors specifically affect marijuana tolerance remains an area for future investigation.
Marijuana potentiation is an area that is generally poorly understood. What is clear is that alcohol can substantially potentiate the effects of marijuana, which may increase the risk of someone participating in risky behaviors. Caffeine may also potentiate marijuana. There are other unverified approaches to marijuana potentiation. For example, some people suggest eating mango 30 minutes before using marijuana to increase levels of the terpene myrcene, which may increase the effects of other chemicals in marijuana. However, others dispute the efficacy of this method. A comprehensive understanding of marijuana potentiation remains unclear.
How to Prevent Marijuana Tolerance
The most effective way to prevent marijuana tolerance is to use it infrequently and at the lowest dose possible. This is simple for most people, but people who use prescription marijuana to ease chronic pain or other conditions face very real challenges when marijuana tolerance becomes an issue. Unfortunately, there is no simple solution for preventing the development of marijuana tolerance in these cases.
Marijuana tolerance breaks, or “t-breaks,” are intermittent pauses on marijuana consumption. Even a few days of abstinence can substantially reduce the tolerance someone has built up. This means that someone who has taken at-break will be more affected by marijuana, so they should start at a lower dose than they were taking when they quit.
Getting Help with Marijuana Addiction
Marijuana dependence certainly occurs, but whether marijuana is addictive is controversial. For people who have found quitting on their own to be challenging, marijuana addiction treatment programs can be a valuable strategy towards recovery.
The Recovery Village Ridgefield offers quality rehab programs that are guided by medical professionals and addiction specialists. Call today to learn how professional rehab can help get you on the road to recovery.
Substance Abuse and Mental Health Services Administration. “Key substance use and mental health indicators in the United States: Results from the 2018 National Survey on Drug Use and Health, Detailed Tables.” Rockville, MD: Center for Behavioral Health Statistics and Quality, August 2019. Accessed September 27, 2019.
Degenhardt, Louisa et al. “The global epidemiology and contribution of cannabis use and dependence to the global burden of disease: results from the GBD 2010 study.” PloS One, October 2013. Accessed September 27, 2019.
National Institute on Drug Abuse. “Is marijuana safe and effective as medicine?” Updated September 2019. Accessed September 27, 2019.
Wells, Janet. “Why Is It So Hard to Study Marijuana?” Medium: UCSF Magazine, June 2017. Accessed September 27, 2019.
National Academies of Sciences, Engineering, and Medicine; Health and Medicine Division. “The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research.” Washington (DC): National Academies Press, January 2017. Accessed September 27, 2019.
Sagar, Kelly A; Gruber, Staci A. “Marijuana matters: reviewing the impact of marijuana on cognition, brain structure and function, & exploring policy implications and barriers to research.” International Review of Psychiatry, June 2018. Accessed September 27, 2019.
Beadle, Alexander. “Cannabis Tolerance: What Does the Evidence Say?” Analytical Cannabis, November 2018. Accessed September 27, 2019.
Gable, Robert S. “Acute Toxicity of Drugs versus Regulatory Status. Figure 7.1: Safety Ratio and Dependence Potential of Psychoactive Drugs.” Drugs and Society: U.S. Public Policy, Chapter 7. Rowman & Littlefield Publishers, Inc., 2006. Accessed September 27, 2019.
National Institute on Drug Abuse. “The Neurobiology of Drug Addiction.” Updated January 2007. Accessed September 26, 2019.
Hirvonen, James K et al. “Reversible and regionally selective downregulation of brain cannabinoid CB1 receptors in chronic daily cannabis smokers.” Molecular Psychiatry, June 2012. Accessed September 27, 2019.
Fugh-Berman, Adriane et al. “Medical Cannabis: Adverse Effects & Drug Interactions.” Government of the District of Columbia, Department of Health. Accessed September 27, 2019.
Hartman, Rebecca L et al. “Controlled Cannabis Vaporizer Administration: Blood and Plasma Cannabinoids with and without Alcohol.” Clinical Chemistry, May 2015. Accessed September 27, 2019.
Onion, Amanda. “Stoned Plus Buzzed: Mixing Caffeine and Pot Brings New Risks.” LiveScience.com, July 2017. Accessed September 27, 2019.
ProfOfPot.com. “How THC Gets Into Your Brain – And How To Increase It.” May 21, 2017. Accessed September 27, 2019.
Russo, Ethan B. “Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects.” British Journal of Pharmacology, August 2011. Accessed September 27, 2019.
National Institute on Drug Abuse. “Is marijuana addictive?” Updated September 2019. Accessed September 27, 2019.
How Long Does Marijuana Stay in Your System?
Cannabis and Pregnancy
How to Talk to Your Teen About Marijuana
Long-Term Effects of Marijuana Use
Marijuana Increases Risk of Cancer
Mixing Marijuana and Alcohol
Is Marijuana Addiction Real?
The Effect of Legalized Marijuana in the Workplace
Teen Vaping May Lead to Marijuana Use
New Study Raises Concerns About Marijuana and Cardiovascular Risk