A 77-year-old female residing at home with probable AD of moderate severity and history of depression for two to three years prior to the onset of AD, was evaluated for increasing agitation and psychosis. Caregivers reported that the patient was sleepless, had intense anger outbursts, persecutory auditory hallucinations, and paranoia. She continually paced, opening drawers, unpacking and repacking their contents.
At the time of evaluation, she was being treated with quetiapine 25 mg and paroxetine 10 mg daily. Based on the physician's discussion with the patient and family the patient did not receive cholinesterase inhibitors. Lithium 150 mg was added and increased from 150 mg to 300 mg daily after two weeks. By week two she had a normal sleep cycle with a marked decrease in paranoia, auditory hallucinations, agitation, and aggression. Her serum lithium level was 0.32 mmol/L after 10 weeks of treatment and she experienced no adverse events.