Some groups of parents and pro-marijuana advocates are calling for cannabis to be considered as a treatment for children and young people with a range of developmental conditions and behavioural issues.
A review paper in the Journal of Developmental & Behavioural Paediatrics, authored by experts from Boston Children's Hospital, highlighted concerns about a number of groups advocating the use of medical marijuana for children with autism, ADHD and other conditions, citing animal research and a small number of clinical reports that claim benefits.
The researchers note that any benefits that have been seen are likely from cannabidiols – currently being looked at for the treatment of rare forms of epilepsy – rather than tetrahydrocannabinol (THC), the psychoactive constituent of cannabis.
This taken together with a growing willingness to prescribe cannabis could lead to the issuing of medical marijuana for developmental or behavioural problems, for which there is insufficient evidence as of yet.
Scott Hadland, John R. Knight and Sion Kim Harris, said this is concerning: "Given the current scarcity of data, cannabis cannot be safely recommended for the treatment of developmental or behavioural disorders at this time."
The authors also say that the lack of research means using medical marijuana for these purposes could result in long-term damage, with the drug harming the developing brain.
"Children with severe ASD cannot communicate verbally and may relate to the world through loud, repetitive shrieking and hand-flapping that is very disruptive to their families and all those around them," Knight said.
"So my heart goes out to families who are searching for something, anything to help their child. But in using medicinal marijuana they may be trading away their child's future for short-term symptom control."
While medical marijuana has been shown to be beneficial for some conditions, such as pain relief, there is also growing evidence to show long-term and possibly irreversible damage to mental and physical health.
Leonard Rappaport, from the Division of Developmental Medicine at Boston Children's Hospital, commented on the paper: "The scant research that we have on adolescent use is alarming enough. But we are really moving into entirely new territory when we consider giving cannabis to children as that has not even been done in neuro-typical children, let alone those with developmental or behavioural problems."
The authors concluded: "At this time, good evidence is almost entirely lacking for its application in paediatric developmental and behavioural conditions."