Key messages
Risperidone and aripiprazole may reduce irritability symptoms, while lurasidone probably results in little to no difference in children with autism.
There is significant uncertainty about the effects of these drugs on aggression, weight gain and abnormal body movements (e.g. tremors) in children with autism.
These medicines may decrease obsessive-compulsive symptoms (unwanted thoughts (obsessions) and repetitive behaviours (compulsions)) and inappropriate speech in children with autism.
We could not thoroughly explore the benefits and harms of these medications in adults with autism as there were few data.
What is autism?
Autism, also known as autism spectrum disorder or autism spectrum condition, is a developmental disorder that affects communication, social interaction and behaviour.
What are atypical antipsychotic medicines?
Antipsychotic medications are primarily used to treat mental health problems, maintaining the balance of certain neurotransmitters (naturally occurring chemicals that allow nerves to communicate throughout the body; for example, dopamine) in the brain to improve a variety of symptoms. Atypical antipsychotics are medications with different benefits and harms compared to typical antipsychotics.
What did we want to find out?
We wanted to compare how well atypical antipsychotics work for reducing irritability in children and adults with autism spectrum disorder. Additionally, we wanted to understand their effectiveness and harms for other symptoms.
What did we do?
We looked for studies that compared different atypical antipsychotic medicines with a placebo (dummy treatment) or with another atypical antipsychotic medicine in people diagnosed with autism spectrum disorder.
What did we find?
We found 17 studies including 1027 people. Most studies focused on children, with only one study involving adults.
Some atypical antipsychotics, such as risperidone and aripiprazole, may reduce irritability in children with autism spectrum disorder over a short period, unlike lurasidone, which probably has little to no effect. Atypical antipsychotic medicines may improve obsessive-compulsive symptoms and may reduce inappropriate speech. We are very uncertain about the effects on aggression, weight gain and unwanted effects related to movement.
What are the limitations of the evidence?
Our confidence in the evidence ranged from moderate to very low. Although we have more confidence in some symptoms and measures, such as irritability, stronger evidence is still needed. We have even less confidence in measures such as weight gain and movement-related unwanted effects, mainly because the studies were small and results varied. In addition, most of the available data were from short-term studies.
How up to date is this information?
The information is current to January 2024.