CBD and Autism: What Research and the FDA Say

CBD and autism is a topic many parents ask about, but research is still early. A few small trials of cannabis extracts in autistic children show mixed results, and CBD is not FDA-approved for autism. Store-bought CBD products are often mislabeled and may contain THC. Talk to your child’s doctor before considering any CBD product.

Why families ask about CBD and autism

Parents often hear about CBD and autism from other families, social media or shops. Many are looking for help with hard problems such as aggression, self-injury, anxiety or poor sleep, especially when other approaches have not worked. Wanting to explore every option is natural. The aim of this guide is to help you weigh the hopes against what is actually known.

What CBD is

CBD (cannabidiol) is one of many compounds in the cannabis plant. Unlike THC, CBD does not cause a “high”. CBD products come as oils, gummies, capsules and drinks, and many are marketed online with claims about calm, sleep or focus.

In the US, the FDA has approved one CBD medicine, Epidiolex. It is approved for seizures associated with Lennox-Gastaut syndrome, Dravet syndrome and tuberous sclerosis complex in patients aged 1 year and older [6]. There are no other FDA-approved drug products that contain CBD [5]. The FDA has also concluded that CBD products are excluded from the definition of a dietary supplement [5], and it warns that some CBD products are marketed with unproven medical claims and are of unknown quality [3].

What the research says about CBD and autism

The largest randomized trial

In a 2021 placebo-controlled, crossover trial, 150 people with autism aged 5 to 21 took a whole-plant cannabis extract, a mix of purified CBD and THC (in a 20:1 ratio), or placebo for 12 weeks each. On the main measure of home behavior problems, there was no difference between groups. On a doctor-rated scale of disruptive behavior, 49% improved on the whole-plant extract compared with 21% on placebo. Social responsiveness scores also improved more on the whole-plant extract [1]. The authors called the efficacy evidence mixed and said more testing is needed [1].

Systematic reviews

A 2024 systematic review found only four studies of CBD-rich cannabis in autism, with 353 participants, and just two were randomized controlled trials. Studies reported some improvements in behavior, social responsiveness and communication, but results for thinking skills were inconsistent. The authors said they were “unable to make conclusive comments” and called for larger, better-controlled trials [2].

In short, the studies so far on CBD and autism are too few, too small and too short to show whether benefits outweigh risks for children.

Why the evidence is weak

Research on CBD and autism has important limits, so early positive reports should be read with caution. Studies used different products, doses and CBD-to-THC ratios. Most outcomes were rated by parents or caregivers. Many participants were also taking antipsychotic or anti-seizure medicines, yet no study measured drug interactions. Treatment lasted only 12 to 26 weeks [2]. We do not know what longer use does to a child’s developing brain [3].

Prescription CBD versus store-bought CBD

There is a big difference between a prescription CBD medicine and a product from a shop or website. Epidiolex has an FDA-approved label, known contents and clear safety monitoring, such as liver blood tests [6]. Store-bought CBD has none of these checks, and its actual contents may differ from the label [7]. Even so, Epidiolex is approved for specific seizure conditions, not for CBD and autism behaviors [6].

Doses used in studies

Because studies used different plant extracts and ratios, there is no standard dose from autism research, and the reviews could not identify a dose-response pattern [2]. Any use should only happen under a doctor’s care, and your doctor will advise whether it is appropriate at all.

Safety concerns with CBD

Side effects seen in autism studies

In the 2021 trial, sleepiness and decreased appetite were the most common side effects, and no treatment-related serious adverse events were reported [1]. Across studies in the 2024 review, reported effects included sleepiness, low appetite, restlessness, anxiety, dizziness and weight gain. Some children had more aggression or repetitive behavior, and a few had seizures [2].

Liver injury and drug interactions

The FDA says CBD can cause liver injury and can affect how other drugs work [3]. The Epidiolex label requires liver blood tests before and during treatment, warns that risk is highest when taken with valproate, and lists interactions with clobazam and several other medicines [6]. Combining CBD with sedating medicines increases sleepiness [3].

Other FDA concerns

In 2023, the FDA highlighted the potential for liver harm, interactions with medicines and possible harm to the male reproductive system. It said safety concerns are greater with long-term use and that exposure is especially concerning for children [4].

Mislabeling and THC

A study of 84 CBD products bought online found only about 30% were labeled accurately for CBD. THC was found in 21% of samples [7]. A separate study found CBD in some melatonin gummies sold in the US [8]. The FDA has also investigated reports of contaminants such as pesticides, heavy metals and THC in CBD products [3].

What you can do at home

• Be cautious about marketing. The FDA warns that unproven products claiming to cure or treat autism are misleading and can cause harm [9]. See our guide to unproven autism treatments.
• Check what is already in the house. Read labels of gummies and sleep products, since some contain CBD [8].
• Store safely. Keep all cannabis and CBD products locked away and out of children’s reach.
• Focus on the goal. If the concern is aggression, anxiety or sleep, ask about treatments with stronger evidence. Our guide to autism medication can help.

Questions to ask your doctor about CBD and autism

• What problem are we trying to solve, and are there better-studied options first?
• Could CBD interact with my child’s current medicines, especially anti-seizure or psychiatric medicines?
• Would my child need liver blood tests?
• Is there a clinical trial my child could join, rather than using a store-bought product?
• What are the laws on CBD and cannabis where we live?

When to talk to a professional

Talk to your child’s doctor before giving any CBD product, and tell them if your child has already taken one. An honest conversation about CBD and autism helps your doctor check for interactions and keep your child safe, and it will not get you in trouble for asking. Seek medical help if a child using CBD becomes very sleepy, confused, yellow in the skin or eyes, has dark urine, stomach pain, or a seizure. If a child swallows a cannabis or CBD product by accident, call your local poison control center or emergency services. See our medical disclaimer.

Frequently asked questions

Is CBD oil approved for autism?

No. The only FDA-approved CBD medicine is Epidiolex, which is approved for seizures linked to Lennox-Gastaut syndrome, Dravet syndrome and tuberous sclerosis complex. No CBD product is FDA-approved for autism. The FDA also says CBD cannot legally be sold as a dietary supplement, and it has warned companies that market CBD with unproven medical claims.

Does CBD help autism symptoms?

The evidence is early and mixed. In the largest controlled trial, 150 young people with autism did not improve on the main home-behavior measure, though one cannabis extract improved some secondary ratings of disruptive behavior and social responsiveness. A 2024 review found only two randomized trials and said firm conclusions are not possible. Larger, longer studies are needed.

What are the side effects of CBD in children?

In autism studies, the most common side effects were sleepiness and decreased appetite. Others included restlessness, anxiety and, in a few cases, more aggression or seizures. The FDA-approved CBD medicine can raise liver enzymes, especially with valproate, and interacts with several medicines. Effects on the developing brain and long-term use are not well understood.

Can CBD products contain THC?

Yes. In one study of 84 CBD products sold online, about one in five contained THC, the part of cannabis that causes a high, and most products were mislabeled for CBD content. Another study found CBD in some melatonin gummies. Because store-bought products are not checked before sale, you cannot be sure what your child is getting.

References

1. Aran A, Harel M, Cassuto H, et al. Cannabinoid treatment for autism: a proof-of-concept randomized trial. Molecular Autism. 2021;12(1):6. Link
2. Jawed B, Esposito JE, Pulcini R, et al. The Evolving Role of Cannabidiol-Rich Cannabis in People with Autism Spectrum Disorder: A Systematic Review. International Journal of Molecular Sciences. 2024;25(22):12453. Link
3. US Food and Drug Administration. What You Need to Know (And What We’re Working to Find Out) About Products Containing Cannabis or Cannabis-derived Compounds, Including CBD. Content current as of March 5, 2020. Link
4. US Food and Drug Administration. FDA Concludes that Existing Regulatory Frameworks for Foods and Supplements are Not Appropriate for Cannabidiol, Will Work with Congress on a New Way Forward. January 26, 2023. Link
5. US Food and Drug Administration. FDA Regulation of Cannabis and Cannabis-Derived Products, Including Cannabidiol (CBD). Link
6. US Food and Drug Administration. EPIDIOLEX (cannabidiol) oral solution: Highlights of Prescribing Information. Revised June 2025. Link
7. Bonn-Miller MO, Loflin MJE, Thomas BF, Marcu JP, Hyke T, Vandrey R. Labeling Accuracy of Cannabidiol Extracts Sold Online. JAMA. 2017;318(17):1708-1709. Link
8. Cohen PA, Avula B, Wang YH, Katragunta K, Khan I. Quantity of Melatonin and CBD in Melatonin Gummies Sold in the US. JAMA. 2023;329(16):1401-1402. Link
9. US Food and Drug Administration. Medication Health Fraud for Specific Diseases and Conditions. Updated January 28, 2026. Link

Professional review: this guide is waiting for review by a qualified clinician. It was written and checked against the published sources listed above. How we check our guides.

This guide is general education, not medical advice. Always talk to your child’s doctor or care team. Last checked: October 2026.