SSRIs for autism: what studies found in children and adults

In one sentence

This Cochrane review found no evidence that selective serotonin reuptake inhibitors (SSRIs) improve core autism symptoms in children, and only limited, unclear evidence in adults from small studies.

What the researchers did

SSRIs are antidepressants often prescribed for anxiety, depression, or obsessive-compulsive symptoms — conditions that commonly occur alongside autism. Some clinicians have also wondered whether SSRIs might help core autism features such as social interaction, communication, or repetitive behaviour.

The reviewers searched databases through March 2013 for randomised controlled trials comparing any oral SSRI with placebo in people with autism spectrum disorder (ASD). They included nine trials with 320 participants in total.

The drugs studied were fluoxetine (three trials), fluvoxamine (two), fenfluramine (two), and citalopram (two). Five trials included only children; four included only adults. Studies used different diagnostic criteria and IQ ranges, and they measured outcomes with many different tools — which made combining results difficult.

What they found

• One large, higher-quality study in children found no evidence that citalopram helped core autism symptoms.
• For children overall, the reviewers concluded there is no evidence of benefit from SSRIs for core features of ASD, and they noted emerging evidence of possible harm — details varied by study and medication.
• In adults, three small studies reported some positive results on global clinical ratings and obsessive-compulsive behaviour; one study reported improvements in aggression and another in anxiety.
• Because studies were small, used different measures, and had unclear risk of bias, the adult evidence was rated as limited.
• The review could not firmly answer questions about quality of life, long-term outcomes, or effects on carers.

What this means for families and therapists

SSRIs are sometimes prescribed for autistic people when anxiety, depression, or obsessive-compulsive symptoms are the main concern — not to “treat autism” itself. This review supports careful, individualised prescribing rather than expecting SSRIs to change core social or communication difficulties.

If a doctor suggests an SSRI, it may help to clarify the specific target symptom, how improvement will be measured, what side effects to watch for, and how long to try the medication before deciding whether it helps.

Families should not start, stop, or change psychiatric medication without medical supervision. Sudden discontinuation can cause withdrawal effects.

Limitations and what we don't know yet

The review is more than a decade old. Newer SSRIs, dosing strategies, and co-occurring conditions may not be fully reflected.

Fenfluramine is no longer commonly used because of safety concerns in other contexts; including older drugs can make the overall picture harder to apply to current practice.

Most adult evidence came from very small samples. Larger trials with consistent outcome measures are still needed, especially for autistic children with intellectual disability and for long-term safety.

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This is a plain-language summary of Selective serotonin reuptake inhibitors (SSRIs) for autism spectrum disorders (ASD) by Williams K, Brignell A, Randall M et al., Cochrane Database of Systematic Reviews (2013). Source license: CC-BY-NC-4.0.

It is not medical advice — talk to a qualified clinician before changing therapy.