Weed and ADHD: What the Research Says

Shot of dried marijuana and a rolled joint

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There is a growing number of individuals who sometimes use marijuana as a self-treatment option for attention-deficit/hyperactivity disorder (ADHD). They state cannabis usage is therapeutic and particularly helpful in limiting distractions, helping with focus, anxiety, and ADHD medication side effects.

However, while it can be helpful for some individuals, much of the research online advise against its use as a primary treatment option. This is because the research into its utility as short-term relief has been mixed.

In addition, research is limited, and more clinical trials need to be conducted before anything can be confirmed. Nevertheless, here is what we know so far.

What Is ADHD?

ADHD is a common neurobehavioral condition that causes changing levels in hyperactivity and impulsive behaviors. While many people experience changes in energy and attention, these tend to happen to a greater degree to those with the condition. For example, it can interfere with the daily functioning of that individual’s life or their life’s achievements.

It is important to note that ADHD is commonly diagnosed in children; however, it also persists in adulthood. For example, it is estimated to affect 11% of school-aged children and an estimated 4.4% of adults.

ADHD Symptoms

The Diagnostic and Statistical Manual of Mental Disorders (DSM) is the handbook used by clinicians and psychiatrists in the United States to diagnose psychiatric illnesses.

As it stands, the DSM-5 identifies 18 total symptoms of ADHD and three possible presentations for ADHD:

  • Predominantly inattentive: This type is characterized by problems regulating attention. Symptoms of this subtype include: being easily distracted by noises and sights, chronic boredom, forgetfulness, trouble organizing tasks, issues staying on task and regularly losing belongings.
  • Predominantly hyperactive/impulsive: This type is characterized by impulsive and hyperactive behavior. When discussing ADHD, this is usually the subtype most people know of, and symptoms include: restlessness, loud and disruptive behaviors, excessive talking, difficulty staying still and feelings of constantly being in motion.
  • Combined type (ADHD-C): This type is diagnosed when symptoms of both inattention and hyperactivity/impulsivity are present.

How Could Cannabis Help With ADHD Symptoms?

There are two components of cannabis that are important to know in order to understand how it might provide relief to those with ADHD:

  • Tetrahydrocannabinol (THC): THC is the psychoactive component that causes people to feel high when they use marijuana. It works by attaching to the body’s cannabinoid receptors, which are found throughout the brain and nervous system.
  • Cannabidiol (CBD): CBD is a nonpsychoactive component in cannabis and hemp. It acts on different areas of the brain and has been found to counteract the effects of THC. It also doesn’t produce a “high;” therefore, it has grown in popularity over recent years.

While most people commonly believe that different strains of cannabis produce different effects, research has shown these differences may not be completely accurate due to extensive cross-breeding.

Nevertheless, indica strains are thought to have a higher proportion of CBD, which research has found to be the most beneficial component for those with ADHD. Also, CBD alone is not addictive; therefore, choosing products without THC may be the better route.

Does Cannabis Effectively Treat ADHD Symptoms?

As mentioned above, the perception that marijuana is therapeutic for ADHD is growing in popularity. For example, a 2016 qualitative analysis of online discussions around cannabis use and ADHD confirmed this trend, finding that overall online discussions indicated that cannabis is considered therapeutic for ADHD.

In addition, a 2020 study on adults with ADHD who took medical cannabis found that those who took a higher dose of medical cannabis components, like CBD, reduced their ADHD medication intake. However, this study was very small; therefore, its results can’t be seen as generalizable to the entire population.

Still, while this view may be gaining in popularity over the internet, there is little clinical support for these claims. For example, a 2013 study found that people with ADHD who used cannabis performed worse on memory, verbal, cognitive, decision-making, and response tests than those who didn’t use the drug. In addition, a 2019 medical review of 83 studies on the matter found that there was insufficient evidence on the effectiveness of cannabis in treating mental health conditions, including ADHD.

So, where does this leave us?

According to Dr. Rebecca Siegel, a licensed psychiatrist, cannabis medical advisor, and author of "The Brain on Cannabis: What You Should Know About Recreational and Medical Marijuana," caution is recommended.

“I have heard from people above the age of 21 that it can help with focus and limit distractions, but I still wouldn’t recommend it as a first-line treatment option,” she says.

She advises people to follow traditional ADHD treatment options until more clinical trials have been conducted on the issue. “Until then, I cannot draw any conclusions on the optimal ratio of CBD: THC,” she finishes. 

Can You Take ADHD Medication and Use Cannabis at the Same Time?

According to Dr. Siegel, the answer to this is complicated.

Rebecca Siegel, MD

I have heard that some adults with ADHD take a combined approach — they use cannabis in addition to other types of options such as medications and/or therapy, but I can’t stress enough the importance of seeking proper treatment before self-medicating.

— Rebecca Siegel, MD

This is because it can lead to people running the risk of suffering from unwanted side effects from mixing cannabis with other medications. For example, a 2015 study of adults without ADHD found the mixture of Adderall and marijuana produced a unique effect on cardiovascular function — that was neither positive nor negative — when compared with either medication taken alone.

While this study wasn’t conducted on people with ADHD, it does highlight the necessity to be cautious. In addition, it highlights the lack of research on whether this treatment method would be useful or practical. For example, using both could potentially limit the efficacy of the medications.

Can I Use Cannabis Instead of ADHD Medication?

Switching your ADHD treatment away from medication to cannabis is strongly unadvised.

This is because cannabis has not been researched extensively enough to be considered an adequate treatment option for ADHD.

However, should you be considering it, it is very important to reach out to your healthcare provider about your thoughts and concerns. Finding a healthcare provider with knowledge on the benefits and risks of using cannabis instead of ADHD medication could be very beneficial to your overall treatment plans.

Risks of Using Cannabis to Treat ADHD Symptoms

It has been estimated that around 30% of people who use marijuana may have some degree of marijuana use disorder.

In addition, those with ADHD have been found to use cannabis two to three times more than adults without ADHD. Therefore, the risks of using the drug can disproportionately affect those with ADHD.

For example, cannabis use disorder (CUD) — a diagnosis given to those with a problematic pattern of cannabis use linked to clinically significant impairment — is twice as likely to occur in those with ADHD. But why?

“Cannabis use for [the] treatment of ADHD symptoms can evolve into CUD if you stray from your initial intention of using cannabis to treat your ADHD symptoms and start to consume it more frequently for unrelated reasons,” says Dr. Siegel.

She states that this is likely due to frequent use evolving into a routine, which can lead to dependence. “Potentially, you may no longer see improvement in your ADHD symptoms if you are consuming it all day long,” she warns, which can lead to people using more cannabis to compensate. Or even an exacerbation of ADHD symptoms. 

Can Using Cannabis Make My ADHD Worse?

Cannabis works by activating the brain’s reward system, releasing dopamine at higher levels than usual. People with ADHD tend to have low levels of dopamine, which is why THC can feel so rewarding. 

So, while using cannabis may make you feel better in the short term, it could lead to CUD and cannabis dependency. Therefore, it is best to stay away from cannabis (or THC products) to be safe, particularly if you are susceptible to substance abuse.

14 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Children and Adults with Attention-Deficit/Hyperactivity Disorder (CHADD). ADHD & Recreational Marijuana: What’s the Attraction?.

  2. Children and Adults with Attention-Deficit/Hyperactivity Disorder (CHADD). Diagnosis of ADHD in adults.

  3. Centers for Disease Control and Prevention. What is ADHD?

  4. National Institute of Mental Health. Attention-deficit/hyperactivity disorder (ADHD).

  5. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, 5th ed.

  6. McPartland JM. Cannabis sativa and Cannabis indica versus “Sativa” and “Indica.” In: Chandra S, Lata H, ElSohly MA, eds. Cannabis Sativa L. — Botany and Biotechnology. Springer International Publishing; 2017:101–121. DOI: 10.1007/978–3–319–54564–6_4

  7. Children and Adults with Attention-Deficit/Hyperactivity Disorder (CHADD). CBD Oil for ADHD? What the Research Says.

  8. Mitchell JT, Sweitzer MM, Tunno AM, Kollins SH, McClernon FJ. “I Use Weed for My ADHD”: A Qualitative Analysis of Online Forum Discussions on Cannabis Use and ADHD. PLoS One. 2016;11(5):e0156614. Published 2016 May 26. doi:10.1371/journal.pone.0156614

  9. Hergenrather JY, Aviram J, Vysotski Y, Campisi-Pinto S, Lewitus GM, Meiri D. Cannabinoid and terpenoid doses are associated with adult ADHD status of medical cannabis patients. Rambam Maimonides Med J. 2020;11(1):e0001. doi:10.5041/RMMJ.10384

  10. Tamm L, Epstein JN, Lisdahl KM, et al. Impact of ADHD and cannabis use on executive functioning in young adults. Drug Alcohol Depend. 2013;133(2):607–614. doi:10.1016/j.drugalcdep.2013.08.001

  11. Black N, Stockings E, Campbell G, et al. Cannabinoids for the treatment of mental disorders and symptoms of mental disorders: a systematic review and meta-analysis. The Lancet Psychiatry. 2019;6(12):995–1010.

  12. Kollins SH, Schoenfelder EN, English JS, et al. An exploratory study of the combined effects of orally administered methylphenidate and delta-9-tetrahydrocannabinol (Thc) on cardiovascular function, subjective effects, and performance in healthy adults. J Subst Abuse Treat. 2015;48(1):96–103. doi:10.1016/j.jsat.2014.07.014

  13. National Institute on Drug Abuse. Is marijuana addictive?

  14. Lee SS, Humphreys KL, Flory K, Liu R, Glass K. Prospective association of childhood attention-deficit/hyperactivity disorder (Adhd) and substance use and abuse/dependence: A meta-analytic review. Clinical Psychology Review. 2011;31(3):328–341. doi: 10.1016/j.cpr.2011.01.006

By Zuva Seven
Zuva Seven is a freelance writer, editor, and founder of An Injustice!. Follow her on Twitter here.