Ask the expert: Can medical marijuana help kids with autism or ADHD?

Dr. Scott Hadland published a review on marijuana and developmental and pediatric conditions.
Dr. Scott Hadland is a general pediatrician and adolescent specialist at Boston Children’s Hospital and recently published a review on marijuana and developmental and pediatric conditions.

Marijuana policy in the United States is changing rapidly, with some states (including every state in New England) legally allowing marijuana to be used for medical reasons. Washington State and Colorado recently voted to allow the recreational use of marijuana, and Massachusetts may hold a similar ballot measure in 2016. It’s no surprise, then, that many parents wonder whether marijuana might have any benefits for certain pediatric conditions, and whether it’s safe for children.

A quick Facebook search shows that a number of groups have cropped up calling for medical marijuana for conditions like autism and attention deficit hyperactivity disorder (ADHD). Some of these online groups point to studies showing that medical marijuana is helpful in these conditions. Other groups tell compelling stories about a child who was struggling with autism whose behavior was dramatically better after being treated with marijuana.

Before doctors recommend a new treatment, we always make sure that carefully conducted studies have answered two critical questions. First, does the treatment actually work? And second, is it harmful? In essence, we need to be sure that the benefits outweigh the risks.

As a pediatrician, I feel tremendous sympathy for families who are seeking new and beneficial therapies for conditions like autism and ADHD. Right now, however, we can’t conclude that the benefits of marijuana outweigh the risks for children.

First, though some families report that their child showed improvement after treatment with marijuana, until careful studies have been conducted involving larger numbers of patients, we can’t be sure that these improvements will extend to other children. Also, we know that marijuana is a sedating substance, so it’s perhaps not a surprise that some patients with difficult-to-control behavior show improvement — but many pediatricians are worried that marijuana is simply improving behavior because it’s sedating to children.

On the other hand, years of research have shown that marijuana does have associated long-term harms. Whereas cigarettes affect the lungs and heart, and alcohol affects the liver, marijuana’s strongest long-term harms are on the developing brain. This means children and adolescents are likely to be the most vulnerable to marijuana’s harms.

The National Institute on Drug Abuse has summarized some of the harms, and they include an 8-point decrease in IQ, and a number of irreversible changes to the brain’s structure and function. There are health effects outside the brain, too, including an intractable vomiting syndrome that can develop among patients who use marijuana regularly.

So, in summary, although you may have heard promising information in the news about using marijuana for conditions like autism and ADHD, right now we simply don’t have good evidence that it is effective — and perhaps more importantly, we know that there are significant long-term harms associated with its use. Keep in mind that generally when pediatricians recommend a medication for a patient, that medication is usually given in a specific dosage and prepared by a pharmacy. The current state of medical marijuana, where available, is that it is sold at a dispensary in a plant form in which neither its contents or concentrations are known.

Before you consider medical marijuana for your child, it is critical to have a conversation with your pediatrician and other specialists to carefully weigh the risks and benefits.

Learn about the Autism Spectrum Center at Boston Children’s.