Severe neurotoxicity associated with low-level serum lithium and risperidone after 25 years of uncomplicated lithium therapy

Lithium neurotoxicity presenting as dementia with therapeutic serum lithium levels

After 25 years of continuous lithium therapy, a woman with moderate intellectual disability and bipolar disorder developed symptoms suggestive of dementia. In fact, she had developed lithium neurotoxicity, but this was overlooked for 18 months as serial lithium levels were in the therapeutic range.