The impact of caffeine consumption on clinical symptoms in patients with bipolar disorder: A systematic review.

The literature examining clinical effects of caffeine in patients with BD is not conclusive. Acute increases in caffeine consumption may precede the occurrence of manic symptoms in patients with BD, potentially through a direct stimulant effect, affecting sleep patterns and/or the metabolism of lithium or other medications, although increases in caffeine intake could also be a consequence of an ongoing manic relapse or a prodromal sign. Further research is needed to determine whether caffeine use impacts the long-term prognosis of BD.