Does Marijuana Help with ADHD Symptoms?

Marijuana is being legalized in some areas for both medicinal and recreational purposes. There is some debate on the internet about whether or not it should be used in an ADHD management plan. I was recently asked on Facebook what my thoughts were about marijuana use for those with ADHD. To be honest, I had never considered it much. It is not legal where I live (South Dakota), so I have never desired to use it or whether or not it could help with my ADHD. That does not mean it is something that is not important to discuss, however. It appears as though marijuana will continue to be legalized in many places, and it remains to be seen what the long-term implications of legalization will be. The more it becomes legal and easily obtainable, the more it will be an important issue to explore within the context of ADHD management. So, after some consideration, here are my thoughts. (Spoiler alert: I do not recommend marijuana use.)

It Is Still Illegal in Many Places

First of all, marijuana is illegal in many jurisdictions. If it is illegal in your jurisdiction, you should not use it. Full stop. No debate.

Anecdotal Evidence Is Insufficient

There are some who say it improves their ADHD symptoms, but that is only anecdotal evidence and far from scientific. Until some scientific studies are done on the matter, all we have to go on are these people’s word. They could be exaggerating, lying, or experiencing a placebo effect. Yes, they could also be telling the truth, but that is insufficient when the potential, serious risks are considered.


There are some potential risks that come along with marijuana use, especially prolonged use. These risks are particularly worrisome for those whose brains are still developing.

Drug Interactions

Some individuals claim that marijuana can help calm some of the side effects of ADHD medication, but there are potential interactions between marijuana and those medications the effects of which could be more serious than the side effects of the ADHD medication. Although, not enough research has been done in this area.


If a person with ADHD tries marijuana even once, they are at risk for using it heavily. A 2014 study (Sibley et al) found that “adolescents with ADHD were 4 to 5 times more likely than controls to escalate to heavy cigarette and marijuana use after trying these substances once.” This escalation increases other risks associated with marijuana use.


When marijuana use escalates, it could develop into cannabis use disorder (CUD). This is concerning for those with ADHD because it could lead to more serious consequences. A 2018 study (Patel et al) “determined that comorbid CUD in patients with ADHD not only increases the risk of acute inpatient care but also prolongs the inpatient stay, thus increasing the healthcare cost.” ADHDers with CUD are more likely to end up in hospitals and stay longer than they other wise would have, and this increases the financial strain of going to the hospital.

Financial Problems

Persistent use of marijuana can cause significant financial problems. A 2016 study (Cerdá et al) found that those “with regular cannabis use and persistent dependence experienced downward socioeconomic mobility, more financial difficulties, workplace problems, and relationship conflict in early midlife.” It goes without saying that financial difficulties can lead to a host of other problems. Not only did this study find a connection between marijuana use and financial problems, but it also found a connection between marijuana use and problems at work and with relationships. In short, frequent marijuana use could cause problems in areas of life in which ADHDers already struggle.


A 2015 study (Riba et al) alludes to previous scientific findings that cannabis users face issues with working and declarative memory deficits. This study notes these deficits go away with abstinence from cannabis use. However, the study sought to find out if marijuana use had any effect on long-term memory. The results of this study show that “abstinent cannabis users have an increased susceptibility to false memories.” Additionally, the authors of the study go on to note that “cannabis users display reduced activation in areas associated with memory processing within the lateral and medial temporal lobe (MTL), and in parietal and frontal brain regions involved in attention and performance monitoring.” Lastly, they found that “cannabis consumption was inversely correlated with MTL activity, suggesting that the drug is especially detrimental to the episodic aspects of memory.” These are drastic long-term consequences for individuals who have stopped smoking pot. This leaves one to wonder what these effects are like in those who have not stopped using it.


While the research is not 100% solid, there does appear to be some strong evidence for a causal relationship between marijuana use and psychosis. A 2014 review (Radhakrishnan, Wilkinson, & D'Souza) found that “[t]he relationship between cannabis and schizophrenia fulfills many but not all of the standard criteria for causality, including temporality, biological gradient, biological plausibility, experimental evidence, consistency, and coherence.” The authors of this review also state their view that, although it is not definitive, this is a strong enough finding for it to influence policy around marijuana.

Moreover, a 2015 study (Di Forti et al) found that “[t]he risk of individuals having a psychotic disorder showed a roughly three-times increase in users of skunk-like cannabis compared with those who never used cannabis.” This indicates that more potent forms of marijuana have an increased likelihood of causing psychosis.

IQ Drop

There is a debate over whether or not marijuana use causes a drop in IQ or other neuropsychological effects. One of the best studies (Meier et al, 2012) done to date found the following:

“Persistent cannabis use was associated with neuropsychological decline broadly across domains of functioning, even after controlling for years of education. Informants also reported noticing more cognitive problems for persistent cannabis users. Impairment was concentrated among adolescent-onset cannabis users, with more persistent use associated with greater decline. Further, cessation of cannabis use did not fully restore neuropsychological functioning among adolescent-onset cannabis users. Findings are suggestive of a neurotoxic effect of cannabis on the adolescent brain and highlight the importance of prevention and policy efforts targeting adolescents.”

A good number of researchers have critiqued this study, but the findings should raise alarm bells, nonetheless. Especially with early onset marijuana use, there are some noticeable risks of negative neuropsychological consequences. Even if the science is not valid, why take the risk?

Short-Term Relief; Long-Term Issues

The anecdotal evidence mentioned above may, indeed, have some validity. However, at what cost? A 2017 study (Bloomfield, Ashok, Volkow, and Howes) found that marijuana use caused an increase of dopamine release which is a chemical the ADHD brain craves. However, this same study found a long-term blunting of the dopamine system. When one considers the long-term consequences of using marijuana to treat ADHD, any short-term benefits do not seem worth the risk.

Today’s Reset ADHD Challenge:

Listen to Nancy Reagan and just say, “NO”


  • Bloomfield, M. A., Ashok, A. H., Volkow, N. D., & Howes, O. D. (2017). The effects of Δ9-tetrahydrocannabinol on the dopamine system [Abstract]. Nature, 539(7629), 369-377. doi:10.1038/nature20153

  • Cerdá, M., Moffitt, T. E., Meier, M. H., Harrington, H., Houts, R., Ramrakha, S., . . . Caspi, A. (2016). Persistent Cannabis Dependence and Alcohol Dependence Represent Risks for Midlife Economic and Social Problems: A Longitudinal Cohort Study. Clinical Psychological Science,4(6), 1028-1046. doi:10.1177/2167702616630958

  • Di Forti, Marta & Marconi, Arianna & Carra, Elena & Fraietta, Sara & Trotta, Antonella & Bonomo, Matteo & Bianconi, Francesca & Gardner-Sood, Poonam & O'Connor, Jennifer & Russo, Manuela & Stilo, Simona & Reis Marques, Tiago & Mondelli, Valeria & Dazzan, Paola & Pariante, Carmine & David, Anthony & Gaughran, Fiona & Atakan, Zerrin & Iyegbe, Conrad & Murray, Robin. (2015). Proportion of patients in south London with first-episode psychosis attributable to use of high potency cannabis: a case-control study. The Lancet.

  • Meier, Madeline H.; Caspi, Avshalom; et al. "Persistent Cannabis Users Show Neuropsychological Decline from Childhood to Midlife," Proceedings of the National Academy of Sciences, August 2012. doi: 10.1073/pnas.1206820109.

  • Patel, R. S., Patel, P., Shah, K., Kaur, M., Mansuri, Z., & Makani, R. (2018). Is Cannabis Use Associated With the Worst Inpatient Outcomes in Attention Deficit Hyperactivity Disorder Adolescents? Cureus. doi:10.7759/cureus.2033

  • Radhakrishnan, R., Wilkinson, S. T., & D'Souza, D. C. (2014). Gone to Pot – A Review of the Association between Cannabis and Psychosis. Frontiers in Psychiatry,5. doi:10.3389/fpsyt.2014.00054

  • Riba, J., Valle, M., Sampedro, F., Rodríguez-Pujadas, A., Martínez-Horta, S., Kulisevsky, J., & Rodríguez-Fornells, A. (2015). Telling true from false: Cannabis users show increased susceptibility to false memories. Molecular Psychiatry, 20(6), 772-777. doi:10.1038/mp.2015.36

  • Sibley, M. H., Pelham, W. E., Molina, B. S., Coxe, S., Kipp, H., Gnagy, E. M., . . . Lahey, B. B. (2014). The role of early childhood ADHD and subsequent CD in the initiation and escalation of adolescent cigarette, alcohol, and marijuana use. [Abstract]. Journal of Abnormal Psychology,123(2), 362-374. doi:10.1037/a0036585