Antidepressants

Depressive symptoms are common co-morbidities of Autism Spectrum Disorder (ASD). However, studies of antidepressants have primarily assessed their efficacy on ASD core symptoms, particularly repetitive behaviour rather than depression possibly because of selective serotonin reuptake inhibitors (SSRI) known for their positive effect on the treatment of repetitive behaviour and obsessive-compulsive behaviour. Other outcomes have included associated symptoms such as irritability, aggression and other problem behaviours. Most publications are case studies. There were only three randomized controlled trials (RCTs) involving tricyclic antidepressants (two on clomipramine and one on tianeptine) showing an equivocal result and were associated with a high rate of adverse events. Most placebo controlled RCTs were on SSRIs (13 studies), findings of which are equivocal, some showing some positive effect and others showing no effect, and some showing more medication related adverse events. Of the three larger studies with reasonable sample size (over 100 participants), two showed a negative outcome and one showed mixed results. Studies have involved children, adolescents, and adults with ASD. On the basis of the evidence available currently it is difficult to draw any definitive conclusion about the effectiveness of antidepressant medications in people with ASD either on the ASD core symptoms or any associated behaviours or symptoms. Therefore, the clinicians must assess possible harm against potential benefit in each case when considering using antidepressants in people with ASD.