Valproic acid in dementia: does an optimal dose exist?

Valproic acid is widely used in the treatment of behavioral disturbances in patients with dementia; however, there is uncertainty about its dosing and studies have reported mixed findings. The current article examines published trials of valproic acid in the treatment of patients with dementia to identify whether an optimal dosing strategy exists. Secondarily, valproic acid dosing from published studies is compared with a real-world 5-year sample of valproic acid prescribing. Twenty studies met selection criteria and were included in the review. Based primarily on uncontrolled trials and the current retrospective study, valproic acid serum levels between 40 and 60 mcg/mL and relatively low doses (ie, 7-12 mg/kg per d) are associated with improvements in agitation in some patients with dementia. At the same time, similar valproic acid levels produced no significant behavioral improvements in most placebo-controlled studies and led to substantial side effects in some patients. Considerable trial design differences exist between controlled and uncontrolled trials. Overall, valproic acid appears to have limited efficacy as monotherapy in many patients with dementia. Its optimal role may be in combination with other psychotropics as a treatment of agitation associated with dementia.