[Acute intoxication with sustained-release lithium carbonate tablets. A propos of a case]

To describe the case of a patient who ingested 50 sustained release lithium carbonate 400 mg tablets, and reached a late peak concentration above 3 mEq/L.

A 32-year-old male with bipolar mood disorder ingested 50 sustained-release lithium carbonate tablets. Upon admission to the emergency room, a gastric wash was performed,from which several tablet remnants were obtained, as well as an intestinal lavage using activated carbon.

good general status, no fever, blood pressure 160/90 mm Hg, no edemas. Neurologic, pulmonary, and cardiac examinations were normal. CBC and the chemistry panel were normal. The patient's psychopathological examination suggested a stable status with no apparent manifestations arising from a decompensated mood disorder. Five hours after his massive lithium ingestion the drug's plasma levels were 0.75 mEq/L. At 22 hours post-ingestion a chemistry panel was obtained, which showed serum creatinin at 1.38 mg/dL and a lithium plasma concentration of 3.15 mEq/L. A hemodyalisis trial was attempted for 4 hours. At 73 hours post-ingestion, lithium plasma levels were 0.6 mEq/L, that is, within therapeutic range. The patient was hemodynamically stable and serial blood tests were normal; he was discharged.

Acute lithium intoxication with plasma levels above 3 mEq/l can be fatal or result in irreversible neurologicsequelae in almost one third of cases, with persistent cerebellar dysfunction in association with dementia of variable degree, andrenal, blood, and liver disturbances. Sustained-release tablets may prolong absorption and delay peak plasma concentrations. In such cases, therefore, it is recommended that drug plasma concentrations be monitored during 48-72 hours post-ingestion.