Some people with ADHD use cannabis or CBD to manage their symptoms. However, there is not yet enough evidence to confirm how it affects ADHD.

The results are mixed and do not advocate the use of the drug for this condition on a medical basis.

Medical cannabis products are still illegal in many states, and research has not proved the suitability of cannabis for treating attention deficit hyperactivity disorder (ADHD).

This article looks at the scientific research and other evidence for and against the potential use of cannabis as a treatment for symptoms of ADHD.

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ADHD is a neurodevelopmental disorder that affects around 6–9% of children and younger adults and about 5% of adults globally.

A person with ADHD might find it hard to focus on tasks, frequently fidget, show signs of restless behavior, and may be unable to stay still or quiet at appropriate times.

ADHD medications can help correct the levels of a neurotransmitter in the brain called dopamine. The medications may have unpleasant side effects. To avoid these adverse effects, some people with ADHD use cannabis as a treatment option.

There remain many unanswered questions about how useful it is, and its safety, especially for children and younger people.

Supporters of cannabis use often claim it is a safe drug and has no risks of addiction. But some opponents call it a “gateway drug,” potentially leading to the use of other drugs, and they claim it is more dangerous than some realize. Many people smoke or eat the plant to produce a “high.”

In recent years, cannabis has made news as an alternative treatment for a variety of health conditions, including pain and mental health problems.

A 2016 study of 268 separate online discussion threads reported that 25% of people said they believed cannabis had a positive role to play in ADHD symptom management. The study points out that research proving a connection between cannabis and the management of ADHD is limited.

Some schools of thought suggest that ADHD might stem from a lack of dopamine in the prefrontal cortex region of the brain.

As a neurotransmitter, dopamine is a chemical that transmits signals between nerve cells in the brain. Dopamine may affect thought processes, including memory and attention.

Substances in recreational drugs such as cannabis can lead to the production of more dopamine in the reward center of the brain.

The brain’s reward center gives an individual a pleasant sensation when they use cannabis and other drugs. But this cycle of recreational drug use and increased dopamine can lead to the development of dependence.

A 2017 study discusses the dopamine-releasing action of tetrahydrocannabinol (THC), an active chemical component in cannabis, and the source of its pleasure sensation. The researchers advised that THC boosts short-term dopamine levels but may dull the system that releases dopamine long term.

This varying effect suggests that even if cannabis provides short-term symptom relief, better focus, or sedation for people with ADHD, longer-term use may result in more harm than good.

One trial from 2017 tested a cannabinoid medication on people with ADHD. While the participant number was small and the findings were not statistically significant, the results did show small improvements in ADHD symptoms. The results also suggested that adults who take cannabinoids for ADHD experience the side effects less than children.

A further review of available clinical evidence on cannabis cited a case that — although not involving ADHD — showed that a child with autistic spectrum disorder had improved hyperactivity levels after receiving a cannabidiol (CBD) treatment.

CBD is a natural compound found in the cannabis sativa plant. Unlike THC, CBD does not produce a psychoactive effect or “high.” CBD is legal in most of the United States and is sold in stores and online.

Researchers have been studying CBD and have found that it may help with mental and physical health issues such as depression, anxiety, and pain management.

There are some studies on CBD and ADHD. A 2019 study compared a THC and CBD combination pharmaceutical with a placebo and found that there were no significant effects on ADHD symptoms.

According to 2020 research, 59 adults with ADHD and access to medical cannabis products self-reported that higher doses of cannabis and its cannabinoids such as CBD, CBN, and terpenes helped with ADHD symptoms. More studies are needed to understand how cannabis and CBD can help manage ADHD symptoms.

The National Institute on Drug Abuse (NIDA) warns that some research suggests there are long-term, negative effects of using THC, especially on the brain during early development. These effects include:

  • slowing cognitive development in children and adolescents
  • increasing risks of depression, anxiety, psychosis, and other mood disorders
  • loss of IQ points, although others have disputed these findings
  • attention, learning, memory, and other brain function problems

The long-term negative effects of using THC may not be the same as using CBD, but there is not enough research to confirm this.

People with ADHD should be cautious about using cannabis, mainly as doctors are unable to advise on safe doses.

The current situation suggests more research is needed to prove that cannabis is a safe and effective treatment for ADHD.

Some research shows a relationship between cannabis dependence and ADHD.

One study of 99 people seeking treatment for cannabis use disorders showed an estimated ADHD prevalence of between 34–46%.

Overall, research seems to indicate that although cannabis seems to alleviate certain short-term effects of ADHD, it may present a heightened risk of dependence and might even make ADHD worse.

There are several ADHD medications. Some of these include:

Methylphenidate is an ADHD medication that researchers tested for interactions with smoked cannabis.

The results showed that the two substances interacted significantly and can increase strain on the heart.

Mounting evidence suggests that the potential side effects from using cannabis are worse in children, and that these adverse effects may outweigh any potential benefits.

The brain of a child is still developing, and using cannabis may alter normal neurological development, leading to harmful cognitive and other effects.

Children and teens that use cannabis may also be more likely to develop dependency.

According to the NIDA, those who start using cannabis before they are 18 years old are four to seven times more likely than others to develop a problem with the drug.

One 2016 study showed that across a 3-year period, the development of alcohol use dependence was more likely among cannabis users than those who were not users.

Some people defend the use of cannabis in children with ADHD based on anecdotal evidence from their personal experience. They may have observed a child or adolescent responding well, with a reduction of ADHD symptoms.

More evidence is needed to prove that cannabis is safe for children and adults to use. Until then, treating children with cannabis and cannabis products continues to carry risks.

Currently, researchers believe that treating ADHD with cannabis can cause short-term reductions in symptoms but potentially serves to make the underlying disorder worse.

For an ongoing neurodevelopmental disorder such as ADHD, people should ensure that they understand the long-term effects of any treatment before they start it.


Should I self-medicate for ADHD by smoking cannabis?


At the present time, there is a lack of sufficient evidence to suggest that cannabis may help with ADHD symptoms.

For many years, researchers did not conduct studies involving cannabis, but now this trend is reversing. I think that, in the years to come, we will see more well-constructed studies that will provide us with significant evidence one way or the other.

Timothy J. Legg, PhD, CRNP Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.

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