[Lithium, a potentially dangerous drug].

Two patients with a bipolar disorder, a woman aged 56 and a woman aged 68, who had used lithium for more than 30 years, were seen with side effects from this medication. Both patients were treated by their general practitioner and had not visited a psychiatrist for many years. The first patient had a chronic lithium intoxication with cerebellar signs and eventually coma, diabetes insipidus, hyperthyroidism, hyperparathyroidism and psoriasis. After 6 weeks of treatment in the intensive-care unit she made a good recovery. The second patient had several lithium side effects. She was diagnosed with diabetes insipidus, hyperparathyroidism due to a parathyroid adenoma, hypothyroidism and a sick-sinus syndrome. A pacemaker was implanted 4 years earlier. The adenoma was surgically removed. After other medication was tried, the patient was once again given lithium, on which she was able to function well. The first patient had lithium concentrations above the therapeutic value for several years and both patients experienced a delay before their signs and symptoms were attributed to lithium. Lithium treatment should be monitored by an experienced psychiatrist.