While lithium is well known for its neurotoxicity, there are very few publications about lithium-induced acute dystonic reaction. We are presenting a clinical case of lithium-induced acute intermittent dystonic reaction in a patient with schizoaffective disorder (SAD). The patient is a 69-year-old African-American male with a long history of SAD, who was treated for many years with ziprasidone and divalproex and was admitted with SAD exacerbation. Due to increased QTC interval, we switched patient to lurasidone. After 2 weeks, due to increased ammonia level, divalproex was switched to lithium (600 mg loading dose and then 450 mg twice/day). Three days later, patient developed a series of intermittent episodes of acute dystonia, manifested as mutism, dysarthria, upper and lower extremity muscle rigidity, dysphagia, and tremor (Table 1). Dystonic reactions responded to benztropine. Eventually, lithium was discontinued and patient did well on a combination of carbamazepine and olanzapine. In this case, we would like to emphasize not only the intermittent but also the atypical presentation of acute dystonic reactions with involvement of large muscle groups, the resemblance to NMS, and a “spectrum” of dystonic reactions rather than one clear-cut presentation. We can only speculate the role lurasidone played in this presentation but reoccurrence of dysarthria on day 54 after lithium was restarted points to its major role.

Table not available.