Mental HealthPending review

Bipolar disorder

A disorder of mood instability in which the same reward-and-arousal circuits that fail low in depression periodically fail high, producing episodes of mania or hypomania that redefine the whole illness and its treatment.

In a nutshell

Bipolar disorder arises from instability of the same mood circuitry that fails low in depression, capable of swinging into pathological elevation (mania/hypomania). A single episode of mania, or hypomania plus depression, secures the diagnosis, and mood stabilisers, not antidepressants, are the backbone of long-term treatment because they dampen swings in both directions.

Classic presentation

A period of elevated or irritable mood with increased energy, reduced need for sleep, grandiosity, pressured speech and impulsive behaviour, occurring alongside a history of depressive episodes.

Key points

Always ask about past hypomania or mania in any patient presenting with depression: its presence changes the diagnosis and the treatment.

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Educational content pending clinical review. Not medical advice.