Letter to the Editor: A Suspicious Bathtub Death in a Suicidal Patienton Mirtazapine

To the Editor:

Mirtazapine is an antidepressant known to function by enhancing noradrenergic and serotoninergic activity. It also has anxiolytic and hypnotic properties. Side effects, such as increased appetite, weight gain, dry mouth, and somnolence, are relatively minor complaints (1[#x02013]4). Unlike other antidepressants, mirtazapine alone has not been involved as a cause of death by overdose. Numerous studies have shown that Mirtazapine overdose in patients resolves well (1[#x02013]7). Therefore, mirtazapine is considered a drug with good tolerability and safety profile.

We here report the case of a female psychiatric patient being treated with mirtazapine for depression and attempted suicide, who was found deceased in her bathtub.

A 67-year-old white woman being hospitalized for major depression and attempted suicide was found lifeless in her bath on the morning of January 20. On January 2, the woman attempted suicide by ingesting a large amount of acetaminophen. She was found by her family and sent to the hospital emergency. Her blood concentration of acetaminophen upon arrival was 2568 umol/L. She was hospitalized for major depression and was started on mirtazapine 30 mg on January 3. By January 16, she was still complaining of insomnia, night awakenings, and depressive symptoms, and the dose was increased to 45 mg. On January 18, she told a nurse that she had been sleeping a lot better over the past 2 days. She was found dead in her bathtub 2 days later.

Her hepatic function was abnormal when admitted to the hospital, but had almost normalized by the time of death (see Table 1).

TABLE 1 Serial liver function tests

	January 3	January 5	January 20
Total bilirubin (normal0–17 µmol/L)	25	23	7
AST (normal 0–31 U/L)	67	296	26
ALT (normal 0–31 U/L)	83	472	58
LDH (normal 230–460 U/L)	404	461	347

The autopsy showed a woman of 1.51 m and 50.45 kg with conjunctival and buccal petechiae. There was cyanosis of the fingertips. At internal exam, there was spume in the airways and the lungs were heavy and oedematous (right lung of 400 g and left lung of 420 g). The cartilage of the neck was intact and there was no hemorrhagic infiltration of the soft tissue. The liver showed mild centrilobular necrosis, compatible with APAP toxicity. Toxicological analysis showed therapeutic concentrations of mirtazapine. The cause of death was concluded to be asphyxia from drowning in the bathtub. Mirtazapine effect on alertness, with excessive sedation, was thought to have played a role in the drowning.