Concomitant lithium and methadone treatment in a bipolar patient: A case report

Dual diagnosis requires complex therapeutic approaches to adapt treatment to the dual nature of the problem. It is important to understand the drug effects and the drug interactions that may be observed during the integral treatment of these pathologies. Given the scarcity of data on the effects of lithium and methadone treatment, the aim of this clinical case report is to explain the interactions produced between methadone and lithium carbonate, in a female patient with medical multi-pathology, opioid-dependent and with comorbid bipolar disorder, who was treated with both drugs. The most common adverse effects for each drug are described. Drug interactions and temporal correspondence of the two drugs, as well as their dosages, are described through review of the retrospective chart and prospective follow-up of the patient. After one-year of follow-up the patient had experienced no interactions in the concomitant lithium and methadone treatment. It should be noted that treatment of bipolar patients with dual diagnosis is complex, and should only be carried out by experts.