LONG-TERM TREATMENT OF BIPOLAR DISORDER

Bipolar disorder is characterised by recurrent episodes of mania and d epression. The major objective of long term treatment is to reduce the frequency of these episodes. Lithium is the most widely recommended d rug for this purpose, having been shown in controlled clinical trials to be more effective than placebo in reducing the likelihood of relaps e. Unfortunately, its effectiveness in clinical practice is less than that predicted from these trials. A major cause of relapse is noncompl iance, largely due to intolerance to adverse effects such as perceived mental sluggishness, thirst, polyuria and weight gain. Regular monito ring of lithium plasma concentrations is required to ensure that the r ange of 0.5 to 0.9 mmol/L is not exceeded. Concentrations above this c an lead to toxic symptoms, which if unchecked can cause brain damage a nd even death. The anticonvulsant drugs carbamazepine and valproic aci d (sodium valproate) are potential alternatives to lithium. Patients w ho relapse frequently despite lithium may benefit from the addition of one of these agents, although formal clinical trial evidence of the e fficacy of such combination treatment is lacking. Antipsychotics, admi nistered as a depot formulation, can reduce the likelihood of relapse in patients with frequent manic episodes, especially if associated wit h poor compliance. Psychological treatment and patient education have been shown to improve outcome, and should be made more widely availabl e to all patients with bipolar disorder.