This article will review the tolerability, side effects, and effectiveness of selective serotonin reuptake inhibitors (SSRIs) in children and adolescents. We aimed to familiarise the readers with the available data on the pharmacological treatment of childhood psychiatric disorders, especially of depressive disorder and obsessive compulsive disorder. Tricyclic antidepressants (TCAs) have questionable efficacy, definite problems with safety (e.g., cardiotoxicity, lethality in overdose, anticholinergic side effects), and compliance issues. Therefore it is suggested suggest that SSRIs should be the first-line treatment for these disorders in children and adolescents. Studies have shown a significant clinical response to SSRIs and their efficiency has been demonstrated in open and controlled trials. It is often recommended that clinicians should start low and go slow when using SSRIs, and maintain the patient in a symptom-free state for at least six months. The side effects of SSRIs are generally mild, manageable, and seldom require discontinuation of treatment. Children should be monitored closely for infrequent side effects such as gastrointestinal upset, headache, and behavioural activation which may be as severe as mania. There is a great need for controlled trials in childhood psychiatric disorders, especially in anxiety disorders.