Pediatric bipolar disorder is a difficult-to-treat recurrent mental illness characterized by a predominant mood state of irritability, and often mixed, rapid-cycling, and psychotic symptoms. Results of randomized controlled trials of lithium, valproic acid, and antipsychotics for early onset bipolar disorder offer hope of improvement for many, yet also demonstrate need for additional treatment options for those children who do not respond adequately to, or cannot tolerate, a first-line mood stabilizer alone or in combination with an atypical antipsychotic. As popular over-the-counter dietary supplements, omega-3 fatty acids represent an appealing option for treatment in the younger bipolar population as they are likely to be better tolerated and cost less compared with conventional mood stabilizing agents. In addition, they have appeal to parents and adolescents due to their perception as a 'natural' substance and relative lack of systemic side effects. To our knowledge, there are no prospective, randomized, controlled trials of flax oil for the treatment of bipolar disorder or selectively evaluating omega-3 fatty acids in the child and adolescent bipolar population.