Shirmila Syamala, Asma Mirghani Sayed Abbas and Hanadi Khamis Mubarak Alhamad
Hamad Medical Corporation, Qatar
Rumailah Hospital, Qatar
Posters & Accepted Abstracts: Prim Health Care
Mirtazapine is an antidepressant commonly used and considered safe in the elderly, especially those suffering from insomnia and weight loss secondary to depression. An 86-year-old frail female was admitted with complaints of poor oral intake. She weighed 23 kilos and was suffering from hypoalbuminemia and electrolyte abnormalities. Her evaluation did not reveal any organic cause for weight loss. Her cognition was intact. She was started on mirtazapine 7.5 mg for depression and after 2 doses; she was unable to sleep and started having visual hallucinations. The hallucinations were described as people in the wall, boxes and cars coming from the window to hit her. Mirtazapine was discontinued and hallucinations stopped 48 hours after the last dose. In patients treated with mirtazapine, somnolence happens in 50% of people and weight gain in 15% of patients. Therefore mirtazapine is commonly used to treat depression in patients with concomitant insomnia and anorexia. The relative tolerability of mirtazapine makes it a first-line medication for many elderlies with major depression. Despite its known sedative effect, there have been reports of visual and auditory hallucinations and insomnia occurring with the use of mirtazapine, which could be related to increase in dopamine levels in the frontal cortex. Our patient was elderly, frail and malnourished. Her hypoalbuminemia and low protein binding could also be a factor as free drug will be available to enter the CNS. Although she was started at half the adult dose, it may still have been high for her due to low weight. As per the Naranjo criteria, mirtazapine was determined as the probable cause of hallucination in this case. Mirtazapine is a relatively safe drug to use in elderly, but one needs to be cautious when starting the drug or increasing the dose, especially in malnourished patients.
Shirmila Syamala is a Diplomate of the American Board of Internal Medicine. She has a special interest in Geriatrics and Polypharmacy in elderly. She is currently working in the Department of Geriatrics at Hamad Medical Corporation, Doha, Qatar.
