Medical cannabis for ADHD
There are first studies on a therapeutic effect of cannabinoid drugs in the sense of a specific positive effect on ADHD symptoms.
In terms of cognitive performance and activity level, a slight but non-significant improvement was observed with Sativex. Hyperactivity/impulsivity (p=0.03) and cognitive inhibition (p=0.05) were significantly improved, and inattention (p=0.10) and emotional lability (p=0.11) tended to improve, although significance was lost after statistical adjustment for multiple testing. One serious (muscle seizures/convulsions) and three mild side effects occurred in the active group and one serious side effect (cardiovascular problems) in the placebo group.
The study concluded that cannabis medication may reduce ADHD symptoms for some adults with ADHD without cognitive impairment.1 A comprehensive metastudy found insufficient evidence of efficacy for ADHD.2
One study found a correlation between high doses of cannabinol (CBN) and reduced self-reported ADHD symptoms, as well as a correlation between high doses of medical cannabis and a reduction or complete substitution of other ADHD medications.3
A comprehensive discussion of THC medications for ADHD can be found at ADHSpedia.4
- 1. Cannabinoid receptors
- 2. Cannabis medication for ADHD
- 3. Effect of THC on dopamine
- 4. Inhibition of sensory overload
- 5. CBD-containing cannabis extract for ASD, anxiety and ADHD
- 6. Cannabis treatment for tic disorders
- 7. Dosage and application instructions for medical cannabis
1. Cannabinoid receptors
There are two cannabinoid receptors.5
1.1. CB1 receptor
The CB1 receptor (cannabinoid-1 receptor) is one of the most abundant receptors in the brain. It is present in many organs, sometimes in low concentrations.
The CB1 receptor is involved in the regulation of:
- Movement coordination
- Spatial orientation
- Sensory perception (taste, smell, touch, hearing)
- Mental performance
- Diclofenac inhibits pain via CB1 receptors, GPR55 receptors, and mu-opioid receptors of mPFC and ventrolateral periaqueductal gray in brainstem6
- Inhibition of excessive signal transduction by neurotransmitters.
Activated CB1 receptors
- inhibit GABA neurons, resulting in less inhibition of dopamine neurons. Thus, cannabinoids indirectly increase dopamine levels
- inhibit overactivity of pain regulation and thus have an analgesic effect
- THC as a CB1 agonist increases dopamine in the nucleus accumbens. Adenosine A2A receptor antagonists (e.g., caffeine) counteract this effect.7
Since the CB1 receptor is not present in the brainstem, which regulates respiration and the cardiovascular system, an overdose of THC should not be able to cause deaths associated with it.
1.2. CB2 receptor
The CB2 receptor (cannabinoid-1 receptor) is primarily associated with the immune system.
2. Cannabis medication for ADHD
In Germany, Sativex, Cannabis Flos, Canemes, Dronabinol are several cannaboid drugs approved, but not for ADHD. For an off-label use in ADHD, an exemption had to be applied for at the BfArM in the past. Since 2017, a medical prescription of Sativex as well as cannabis flos for ADHD is permitted under the BtmG without an additional exemption 8
As of 2017, approximately 150 ADHD sufferers had received waivers (out of a total of 1061 granted).9
We now know of a double-digit number of reports from sufferers, as well as several sufferers personally, for whom medical cannabis has significantly reduced ADHD symptoms after MPH and amphetamine medications had failed to have an adequate effect.
In a case of an apparently massive THC addict who is allowed to consume THC in a controlled manner, it is open whether this is based on the same effect or whether the effect is explained by the fact that the THC has merely eliminated the withdrawal symptoms of an existing THC addiction. This pattern is also known in alcohol addicts who function “better” with their base dose because the withdrawal symptoms are masked.
Cannaboid drugs may be prescribed in Germany for ADHD as a BtM prescription (like stimulants) if other drugs are ineffective. Health insurance companies usually reimburse the costs upon application.
3. Effect of THC on dopamine
THC indirectly increases dopamine levels in the brain.
The THC cannabinoids do not act directly on dopamine neurons, but on the endocannabinoid system. Cannabinoid receptors are found in many brain areas that have dopamine neurons. Dopamine neurons themselves do not have cannabinoid receptors. However, dopamine neurons are inhibited by GABA neurons, which in turn have cannabinoid receptors.
THC activates CB1 receptors on GABA neurons, which inactivate the GABA neurons. Thus, the GABA neurons that inhibit the dopamine neurons are deactivated. As a result, the dopamine neurons are less inhibited and thus more active.1011
THC as a CB1 agonist increases dopamine in the nucleus accumbens. Adenosine A2A receptor antagonists (e.g., caffeine) counteract this effect.7
For the difference between medications and drugs, see ⇒ Medications and drugs - the difference.
4. Inhibition of sensory overload
Endocannabinoids (cannabinoids produced naturally in the body) also act on the CB1 receptors, causing, among other things, protection against stimulus overload.12
5. CBD-containing cannabis extract for ASD, anxiety and ADHD
One study treated a small group of ASD sufferers with a CBD-enriched cannabis extract. The CBD to THC content was 75 to 1. Almost all sufferers found improvements after 6 to 9 months, with ADHD symptoms often improving. Improvements were most pronounced in nonepileptic sufferers.13
Several sufferers told us that CBD oil (without THC) did not improve their ADHD symptoms.
However, a significant improvement was reported in anxiety disorders. Several sufferers reported that CBD oil enabled them to significantly reduce the previous dosage of their anxiety medication.
6. Cannabis treatment for tic disorders
A small study looked at the treatment of tic disorders with cannabis. Tics were found to improve by 60% in 85% of those affected, comorbidities (most commonly OCB / OCD, ADHD, and sleep disorders) improved in 55%, and quality of life improved in 93%. The effects were estimated to be long-term. Half reported side effects, although their severity was judged to be tolerable. THC-rich strains seemed to work better.14
Tic disorders share a genetic basis with ADHD.
7. Dosage and application instructions for medical cannabis
Instructions on how to dose medical cannabis (Cannabis Flos) using a vaporizer can be found here.15
Cooper, Williams, Seegobin, Tye, Kuntsi, Asherson (2017): Cannabinoids in attention-deficit/hyperactivity disorder: A randomised-controlled trial, European Neuropsychopharmacology, Volume 27, Issue 8, 2017, Pages 795-808, ISSN 0924-977X, https://doi.org/10.1016/j.euroneuro.2017.05.005. n = 30 ↥
Black, Stockings, Campbell, Tran, Zagic, Hall, Farrell, Degenhardt (2019): Cannabinoids for the treatment of mental disorders and symptoms of mental disorders: a systematic review and meta-analysis. Lancet Psychiatry. 2019 Oct 25. pii: S2215-0366(19)30401-8. doi: 10.1016/S2215-0366(19)30401-8. ↥
Hergenrather, Aviram, Vysotski, Campisi-Pinto, Lewitus, Meiri (2020): Cannabinoid and Terpenoid Doses are Associated with Adult ADHD Status of Medical Cannabis Patients. Rambam Maimonides Med J. 2020 Jan 30;11(1):10.5041/RMMJ.10384. doi: 10.5041/RMMJ.10384. PMID: 32017685. n = 27 ↥
Tamaddonfard, Erfanparast, Salighedar, Tamaddonfard (2020): Medial prefrontal cortex diclofenac-induced antinociception is mediated through GPR55, cannabinoid CB1, and mu-opioid receptors of this area and periaqueductal gray. Naunyn Schmiedebergs Arch Pharmacol. 2020 Mar;393(3):371-379. doi: 10.1007/s00210-019-01735-x. PMID: 31641818. ↥
Justinová, Ferré, Redhi, Mascia, Stroik, Quarta, Yasar, Müller, Franco, Goldberg (2011): Reinforcing and neurochemical effects of cannabinoid CB1 receptor agonists, but not cocaine, are altered by an adenosine A2A receptor antagonist. Addict Biol. 2011 Jul;16(3):405-15. doi: 10.1111/j.1369-1600.2010.00258.x. PMID: 21054689; PMCID: PMC3115444. ↥ ↥
Friend, Weed, Sandoval, Nufer, Ostlund, Edwards (2017): CB1-Dependent Long-Term Depression in Ventral Tegmental Area GABA Neurons: A Novel Target for Marijuana. J Neurosci. 2017 Nov 8;37(45):10943-10954. doi: 10.1523/JNEUROSCI.0190-17.2017. ↥
Fleury-Teixeira, Caixeta, Ramires da Silva, Brasil-Neto, Malcher-Lopes (2019): Effects of CBD-Enriched Cannabis sativa Extract on Autism Spectrum Disorder Symptoms: An Observational Study of 18 Participants Undergoing Compassionate Use. Front Neurol. 2019 Oct 31;10:1145. doi: 10.3389/fneur.2019.01145. eCollection 2019. ↥
Milosev, Psathakis, Szejko, Jakubovski, Müller-Vahl (2019): Treatment of Gilles de la Tourette Syndrome with Cannabis-Based Medicine: Results from a Retrospective Analysis and Online Survey. Cannabis Cannabinoid Res. 2019 Dec 9;4(4):265-274. doi: 10.1089/can.2018.0050. eCollection 2019. ↥