Purpura Associated With Lithium Intoxication

A 51-year-old male with bipolar disorder experienced purpura, a skin condition characterized by red or purple discolorations, after being treated with lithium carbonate. Despite his blood lithium levels being within the therapeutic range (1.01 mmol/L), he developed purpura, suggesting lithium intoxication. The case highlighted that lithium can cause platelet dysfunction, potentially through immune complex mechanisms, even at normal therapeutic levels. The patient's condition improved after discontinuing lithium and administering mannitol, with a subsequent decrease in lithium concentration and resolution of purpura. This case underscored the importance of monitoring patients for early signs of lithium intoxication, even when blood levels are within the normal range.