Although some partake in medical or recreational cannabis to help ease ADHD symptoms, anecdotal evidence has intrigued researchers — and some medical professionals.

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Some folks with attention deficit hyperactivity disorder (ADHD), a neurodevelopmental condition, report that CBD — a chemical in the cannabis plant — improves their symptoms.

I thought it was called marijuana? Language matters

The term “cannabis” is preferable to marijuana and will be used throughout this article. The latter term has racist roots and connotations.

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Dr. Benjamin Caplan, chief medical officer of CED Clinic and EO Care, says that data science and crowdsourced experiential research increasingly link cannabis to positive treatment outcomes. He reports seeing cannabis improve ADHD symptoms such as inattention and anxiety in the patients he treats.

While some medical professionals think this self-medication suggests the benefits of cannabis as a treatment, others worry that it could lead to cannabis use dependence.

Cannabis is not legal on the federal level, but as of June 2022, 38 states have legalized the medical use of cannabinoids to varying degrees.

Teen use

Results of a 2018 analysis of three population-based studies on twins showed an association between ADHD and adolescent alcohol and cannabis use:

  • Folks with more childhood ADHD symptoms were more likely to start drinking and using cannabis at a young age.
  • Adolescents with ADHD were also more likely than peers without ADHD to increase their alcohol and cannabis use.
  • Greater symptoms of hyperactivity-impulsivity in females equated to higher substance use and escalation than in males.
  • Teens of both genders with inattentive symptoms tended to use more cannabis than alcohol.
  • In identical twins, those with more intense ADHD symptoms did not show different alcohol or cannabis use patterns than their fellow twin.

The researchers concluded that genetics and family culture or shared ADHD traits within the family as a whole may influence alcohol and cannabis use among folks with ADHD.

ADHD does not seem to directly cause early or high rates of cannabis use.

How cannabis might affect ADHD symptoms


Researchers for a 2017 randomized control trial, accounting for a tendency for cannabis treatment to relieve ADHD-influenced inattention, speculated that cannabis might help deliver dopamine. Dopamine levels are low in the brains of folks with ADHD.


Caplan describes the effects of cannabis on focus this way:

  • Cannabis may form new signal patterns as the chemical flows through the bloodstream.
  • The flood of new signals might overrun the inattention or hyperactive signals in queue.
  • The cannabis consumer may be able to have improved concentration and some executive function improvements.

Caplan says he sees many patients in Massachusetts, around the country, and internationally who report increased efficiency in accomplishing tasks at school or at work while consuming cannabis.

Forum threads buzzing

A 2016 qualitative study analyzed 401 posts from online forum threads. Despite the lack of clinical evidence supporting the use of cannabis for folks with ADHD, many individuals themselves, sometimes with the support of their doctors, believe the use of cannabis improves their ADHD symptoms:

  • 25% of the posts suggest cannabis use reduces ADHD symptoms, compared to 8% suggesting cannabis makes ADHD worse
  • 61 posts described improvements in one of the three ADHD types
  • common references pointed to cannabis’ benefits for improved attention and reduced hyperactivity
  • A fair number of posters referenced the support of their doctors regarding their cannabis use for ADHD treatment

Self-reports suggest improved depression and ADHD symptoms

A 2022 case report shows that after receiving cannabis treatment, three participants, all males, ages 18-23, improved in the following areas:

However, researchers noted that larger clinical trials are needed to confirm the positive effects of cannabis treatment for those with ADHD.

A 2021 study of 1,738 student online survey participants with ADHD concluded that many felt cannabis relieved their ADHD medication side effects such as irritability.

Mismatched or unregulated dosing

The American Psychiatric Association (APA) published a position statement in 2019 against medical cannabis as medication. Since cannabis is not FDA approved, its use, the APA said, is still unregulated and unbacked by science “for the treatment of any psychiatric disorder.”

Even in states where cannabis is legal, a buyer isn’t assured of:

  • quality
  • strength
  • correct dosage


Caplan suggests that a dependence on medication to treat a problem is not necessarily an addiction and that a dependence on cannabis to treat ADHD may be no worse than repeatedly drinking coffee.

A 2019 report for Children and Adults with Attention-Deficit Hyperactivity Disorder (CHADD) presents a concern that cannabis use may pose a particular risk of dependence for folks with ADHD. They say, especially in young ones:

  • Long-term (unlike short-term) use of cannabis has been shown to suppress the dopamine system, which is already lacking with ADHD.
  • Self-medicating might involve trying to get a dopamine rush that is harder and harder to obtain.

The National Institute on Drug Abuse (NIDA) suggests that teen cannabis users are 4–7 times more likely to develop a dependency than adults.

Dependence in adolescents involves cannabis withdrawal symptoms, such as:

  • sleeplessness
  • irritability
  • memory issues

Given the evidence of folks with ADHD who start using cannabis at a younger age, the likelihood of their developing a dependency is higher than for those without.

Worsening ADHD symptoms and mental health challenges

The 2019 CHADD report also flags the similarities between cannabis use symptoms and ADHD symptoms in the areas of:

This overlap may worsen symptoms or cause confusion with diagnosis.

The National Alliance on Mental Illness (NAMI) reports cannabis use may trigger or escalate mental health problems, like schizophrenia or psychosis.

NAMI advocates for caution until more clinical studies have investigated the long-term effects of cannabis on the brain.

Caplan says that, compared with side effects of standard ADHD medication, the adverse effects of cannabis are often mild:

Side effects of ADHD RxSide effects of cannabis
dry mouth
ticsdizziness, light-headedness
decreased growth in kidsproblem-solving interference
appetite suppression (amphetamines)decreases appetite
nauseadigestive changes: relaxes digestive tract, possible diarrhea
sleep interference (amphetamines)possible drowsiness
hormone fluctuations (antidepressants)mood changes: irritability and agitation
increased anxiety, jitterinesspossible increased anxiety
increased heart rateincreased heart rate

In a 2020 cross-sectional study of 59 adults with ADHD and access to medical cannabis, participants self-reported that higher doses of both cannabidiol (CBD) and cannabinol (CBN, another cannabis derivative) helped with ADHD symptoms, so much so that those adults weaned off their ADHD medication.

Caplan observes that cannabis may interact with other medications, sometimes in a supplemental manner, sometimes in counterproductive ways. He warns that anyone concerned about interactions should speak with a doctor or their local pharmacist.

Cannabis vs. CBD

Cannabis is to CBD and THC similar to what the aloe plant is to aloe vera gel. CBD, THC, and other cannabis extracts are reputed to treat some health conditions in nuanced ways.

Caplan explains that the effects of THC tend to be most felt as change in emotions and cognition. CBD mostly affects body relaxation and inflammation.

“The cannabinoids do interact with each other,” Caplan says, “often buffering the effects of one another toward an average end result.”

Much is clinically unproven about the use of cannabis to treat long-term ADHD.

If you’re under 21, using cannabis to medicate your ADHD may pose more risks than positive effects. Experiential evidence suggests that cannabis use may have some benefits for some adults with ADHD.

If you think trying cannabis for your ADHD may be a wise option, you can talk with your medical practitioner about the best varietal, method, and dosage for your treatments.

Is CBD legal? The 2018 Farm Bill removed hemp from the legal definition of marijuana in the Controlled Substances Act. This made some hemp-derived CBD products with less than 0.3 percent THC federally legal. However, CBD products containing more than 0.3 percent THC still fall under the legal definition of marijuana, making them federally illegal but legal under some state laws. Be sure to check state laws, especially when traveling. Also, keep in mind that the FDA has not approved nonprescription CBD products, and some products may be inaccurately labeled.