Weed and ADHD: What the Research Says

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 is not addicting. This is one reason 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.

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.

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.

Can I Use Cannabis Instead of ADHD Medication?

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

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.

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.