Symptoms of lithium toxicity at therapeutic levels
Roerdink, S.J.; Veth, C.P.M.; van Pamelen, J.; Manuputty, J.; Swolfs, S.N.
Nederlands Tijdschrift Voor Geneeskunde 163
2019
ISSN/ISBN: 1876-8784 PMID: 31769628 Document Number: 699623
A 60-year-old woman was admitted to the medical psychiatric unit with neurological and psychiatric symptoms. She was being treated with a maintenance dose of lithium for bipolar I disorder. Lithium toxicity and manic state were both considered. However, serum lithium levels appeared to be non-toxic. During hospital admission, her symptoms worsened and many diagnostic tests were performed. Lithium toxicity was considered again and lithium was discontinued, despite therapeutic blood levels. The neuro-psychiatric symptoms subsequently disappeared and the patient improved without residual symptoms. When neuro-psychiatric symptoms occur without elevated lithium levels, the possibility of chronic lithium toxicity should still be considered. More caution is required when risk factors are present, such as: old age, interacting medication, reduced renal function, dehydration and fever. Finally, electroencephalography can contribute to the diagnosis of chronic lithium toxicity.