The aim of this study was to review current epidemiological data on the use of antidepressants in co-prescription with other psychotropic drugs in children and adolescents, as well as available efficacy and safety information. A Medline search from inception until February 2012 was performed to identify epidemiological and clinical studies, reviews and reports containing potentially relevant information on polypharmacy with antidepressants in young people. There has been an increase in polypharmacy in children and adolescents involving antidepressants in recent years. Antidepressants have become one of the drug classes most frequently prescribed in combination and are commonly co-prescribed with stimulants and antipsychotics. Most information regarding efficacy and safety of polypharmacy patterns was provided by case series and open-label studies. Efficacy studies gave some support for the use of a combination of antidepressants and antipsychotics in the management of refractory obsessive–compulsive disorder and some residual symptoms in major depressive disorder. Even less empirical support was found for a combination of stimulants and antidepressants in co-morbid attention deficit hyperactivity disorder and mood or anxiety disorders. Adverse events were similar to those found with individual medication groups, with severe adverse events mostly reported by individual case reports. The use of polypharmacy with antidepressants has become a regular practice in clinical settings. Although there is still little efficacy and safety information, preliminary evidence points to the potential clinical usefulness of some polypharmacy patterns. Further research on patients with co-morbidities or more severe conditions is needed, in order to improve knowledge of this issue.