Valproic acid has been proven to be efficient in the treatment of bipo
lar affective disorders as an adjunctive agent to lithium and carbamaz
epine. Recently, its efficacy in rapid cycling states has attracted in
terest. We present the case of a male patient with bipolar affective d
isorder who developed an extreme state of ultrarapid cycling (48-h cyc
les). Only the addition of valproic acid therapy to prior lithium trea
tment succeeded in curtailing the ultra-rapid cycling. Several issues
regarding ultra-rapid cycling and valproate's efficacy in bipolar diso
rder are discussed.