For someone living with attention deficit hyperactivity disorder (ADHD), life can feel like everything is happening all at once. As Edward Hallowell, MD, reflects, ADHD is “like being super-charged all the time. You get one idea and you have to act on it, and then, what do you know, you’ve got another idea before you’ve finished up with the first one… all these invisible vectors are pulling you this way and that, which makes it really hard to stay on task.”
This pull to go in different directions can create a sense of inner turmoil or panic, making it hard to focus or prioritize. While a range of behavioral therapies and medications can help manage the disorder, cannabis has steadily received attention as an alternative treatment. Is there evidence that cannabis can ease or manage symptoms associated with the condition?
What is ADHD?
ADHD is a neurodevelopmental disorder, and it’s the most commonly diagnosed childhood behavioral disorder. Although children can grow out of ADHD, the condition can persist into adulthood for one-third of those people.
The number of individuals diagnosed with the disorder has been rising rapidly in recent decades. In the 1980s, one in 20 US children was diagnosed with ADHD. Nowadays, that number is roughly one in nine. Adult rates of ADHD have also risen by 123% between 2007 and 2016. Approximately 2.58% of adults have ADHD.
ADHD is diagnosed by the presence of symptoms of inattention and hyperactivity or impulsivity.
The diagnosis process for adults and adolescents 17 and over is slightly different from that of children, but the symptoms that physicians check for remain the same:
- Not paying close attention to details or making careless mistakes in schoolwork, at work, or with other activities
- Difficulty in maintaining attention on tasks or play activities
- Not listening when being spoken to directly
- Not following through on instructions and failing to finish schoolwork, chores, or duties in the workplace
- Difficulty in organizing tasks and activities
- A reluctance to engage in tasks that need focus over a period of time (like a long-term project)
- Losing things that are needed for tasks and activities, e.g., school materials, tools, paperwork, mobile telephones
- Getting distracted
- Forgetting things
Symptoms of hyperactivity and impulsivity can include:
- Fidgeting, tapping hands or feet
- Moving about or being restless in situations where it would be appropriate to sit still
- Difficulty in playing or taking part in activities quietly
- Excessive talking
- Blurting out an answer before a question has been asked
- Finding it hard to wait in queues or wait for one’s turn
- Interrupting or intruding (for example, butting into conversations or games)
However, individuals living with ADHD often emphasize that the disorder isn’t just a collection of symptoms. Instead, it can also be a unique way of experiencing life. While ADHD presents distinct challenges, some diagnosed with the disorder believe it to have special benefits, such as boundless energy, creativity, and an interest in diverse topics.
Why do people with ADHD use cannabis?
Doctors who diagnose ADHD generally prescribe behavioral therapy, medicine, or both. Treatment can include stimulants, such as Adderall and Ritalin, or non-stimulants, like Clonidine or Guanfacine. Stimulants are usually prescribed first, and if they don’t work, then non-stimulants may be tried.
However, for some parents of children with ADHD (and some adults), this treatment approach doesn’t produce the desired results—or can cause unwanted side effects.
For example, in one study, 21% of parents ceased giving ADHD medication to their children because of psychological side effects or the perception that the medicine wasn’t working. Behavioral therapy can also be limited in its results as it doesn’t change the symptoms of ADHD, but teaches skills to manage the condition more easily. What’s more, both treatment approaches can be costly.
Instead of these conventional medications, increasing numbers of individuals choose to self-medicate with cannabis. Unfortunately, research into cannabis as a treatment for ADHD is scarce. There’s currently no robust clinical data that clearly supports the idea that cannabis is therapeutic for ADHD. However, an absence of clinical data doesn’t necessarily mean it doesn’t help.
Case studies, surveys, and anecdotal reports often suggest that cannabis can help support sleep, focus, anxiety, or slowing thoughts.
For example, a study of 401 online forum threads about ADHD and cannabis found that 25% (99 posts) of contributors felt that cannabis improved ADHD or its symptoms. In contrast, 8% found that it was harmful (31 posts). Five percent believed that it was both therapeutic and detrimental (19 posts), and 2% shared that it didn’t affect their condition.
A 2022 case study reported that three adult men who added cannabis to their treatment regimen found it offered diverse therapeutic benefits. Scores on attentiveness rose by up to 30%. Two of the men also shared that they were able to improve their performance in their job and take on more responsibility.
Also in the study, depression improved by up to 81%, anxiety scores lifted by up to 33%, emotional regulation scores elevated up to 78%. The men varied in the type of cannabis they used: one preferred high-THC low-CBD, and another preferred low-THC and high-CBD.
How can different cannabinoids and terpenes affect ADHD?
New research hints that different cannabinoids, or combinations of cannabinoids and terpenes, may offer therapeutic benefits to individuals with ADHD. These findings suggest that using cannabis to treat ADHD symptoms is nuanced.
A combination of THC and CBD
In one of the only randomized clinical trials using cannabis for adults with ADHD, researchers gave participants Sativex spray, a pharmaceutical form of cannabis that contains equal parts THC and CBD, for six weeks. Researchers measured two outcomes: The primary outcome focused on cognitive performance and activity during a 20-minute task; the secondary outcome included hyperactivity, inhibition, and attentiveness.
Researchers discovered that the spray didn’t negatively affect participants’ cognitive performance. Sativex did lead to an improvement, however, in the secondary outcomes, with a reduction in hyperactivity, feeling better equipped to inhibit behavior, ability to regulate emotion more easily, and more attentiveness. The researchers suggested that these improvements could be because both THC and CBD can alleviate anxiety.
A study of children in Israel also found that a combination of high CBD and low THC (in a ratio of 20:1) helped manage hyperactivity, insomnia, and anxiety. While this study focused on 53 children diagnosed with Autism Spectrum Disorder (ASD), the disorder shares major symptoms with ADHD, such as trouble focusing, impulsivity, insomnia, and hyperactivity. Between 50-70% of individuals with ASD are also diagnosed with ADHD. Some experts believe ADHD and ASD both fall on the same continuum.
The researchers found that 68.4% of the children experienced an improvement in hyperactivity symptoms, 71.4% began sleeping better, and 47.1% had a reduction in anxiety symptoms. However, for a small percentage of the children, these symptoms worsened.
CBD (cannabidiol)
In a 2020 systematic review, researchers awarded CBD a “Grade B” recommendation to support its use in treating symptoms associated with ADHD, meaning there’s a moderate level of evidence to support its use.
A clinical trial exploring the use of CBD-rich oil for ADHD is also currently underway. According to the research proposal, the study aims to uncover more about how the cannabinoid affects ADHD symptoms, stating that “data on the effects of cannabidiol rich cannabis extract use for ADHD seems promising but is still limited.”
CBN (cannabinol)
CBN has also shown promise in the treatment of ADHD. In one creative study, individuals with ADHD who consumed cannabis with high concentrations of CBN experienced a reduction in self-reported symptoms, however, the study didn’t specifically explain which symptoms improved.
Terpenes
In the above study, researchers also found that higher doses of whole-plant cannabis—cannabis containing a range of cannabinoids and terpenes—were associated with patients decreasing their ADHD medicine.
The study didn’t share any firm findings about which terpenes appeared the most beneficial for ADHD symptoms. However, the researchers emphasized that terpenes and cannabinoids work together synergistically in complex ways—a phenomenon known as the entourage effect—and that there was still much to learn about how these combinations affect ADHD. For example, specific combinations of terpenes and cannabinoids may help to promote focus or calm the mind.
What are the risks of using cannabis to treat ADHD?
Since there’s a lack of research into cannabis and ADHD, it follows that there’s also little robust data about risks. That being said, some studies have explored the connections between cannabis, ADHD, executive function, and addiction.
Executive function
In a study exploring the effects of ADHD and cannabis use on executive function, researchers found no evidence that cannabis caused detrimental effects to individuals with ADHD. Executive function includes the ability to regulate emotions, remember things you’ve just been told, and practice self-control. However, those who started using cannabis before 16 had poorer performance than those who used cannabis in later years.
Addiction/cannabis use disorder
There’s also a correlation between ADHD and cannabis use disorder. For example, research into young adults with ADHD suggests that the condition is linked to a higher prevalence of cannabis addiction. In a Canadian survey of 6872 respondents aged 20-39, individuals with ADHD were 1.5 times more likely to have cannabis use disorder.
However, individuals with ADHD are significantly more likely to have a substance use disorder in general, such as alcoholism. It’s not that cannabis is particularly addictive for individuals with ADHD, rather, there’s a possibility of developing an addiction to any substance that can manage mood, help with sleep, or work as a form of self-medication.
