SOFT 2004 Meeting Abstracts - Society of Forensic Toxicologists

P13
MIRTAZAPINE-RELATED DEATHS
R A Braithwaite* and S P Elliott
Regional Laboratory for Toxicology, City Hospital, Birmingham. UK
Mirtazapine is a novel antidepressant drug which has a pharmacological action on both noradrenergic and
serotonergic systems. The drug has been on the US and European markets for about 10 years, but
relatively few deaths associated with mirtazapine have been reported in the literature. Post-mortem blood
mirtazapine concentrations of up to 0.3 mglL have been reported in cases where the drug is not implicated
in the cause of death. There is also evidence to show that the drug undergoes post-mortem redistribution,
which can make interpretation offindings more difficult.
Relatively few deaths reported in UK have noted the presence of mirtazapine. However, in the last few
years (2001-2003) the Laboratory has investigated a total of 8 cases (5 male, 3 female) aged between 17
and 77 years where mirtazapine has been found to be present in significant concentrations, but generally in
association with other drugs. Post-mortem blood mirtazapine and its desmethyl metabolite
(normirtazapine) have been measured using liquid chromatography with U.V-diode array detection. In
addition, extensive screening of blood and other fluids was undertaken to determine the presence of other
drugs and alcohol.
Details of the 8 cases investigated are shown in the Table below. In 7 of the 8 cases blood was taken from
a peripheral site at post-mortem. Post-mortem blood mirtazapine concentrations ranged between 1.0 - 404
mglL (mean 2.1 mglL) The ratio of mirtazapine to normirtazapine concentrations ranged between 1.9 and
20.
Age Sex Site oj Mirta:: Normirta= MirtiN ormirta:: Other drugs present and
Collect (mgIL) (mgIL) Ratio (concentrations mglL)
/~...
75 M Femoral 2.2 OJ 7J Temazepam, (2.2), venlafaxine
(3.6). Found dead at home
46 M Femoral 2.0 20 Temazepam (Ll) ethanol
(214 mg/dL). Found dead at home
60 M Unknown 1.6 0.8 2.0 No other drugs detected. Found
dead in river
56 M Femoral 1.0 OJ 3.3 Diazepam (1.5), Sildenafil (trace),
alcohol (72 mg/dL). Found dead at
home
77 M Femoral 2.1 1.1 1.9 Zopic1one (1.6). Found dead in bed
51 F Femoral 2.5 004 6.7 Zopiclone (1.7), Lorazepam (004),
chlorpromazine (trace), alcohol
(54 mgldL). Found dead in bath
21 F Common 1.3 0.3 5.0 Dextropropoxyphene (2.4),
Iliac
Paracetamol (124), Venlafaxine
(1.4) Zopidem (trace). Found dead
at home
17 F Femoral 4.4 0.7 6.1 Diltiazem (4.2), paracetamol (70),
Zopic1one (trace). Found dead at
home with suicide note
In conclusion, mirtazapine appears to be more commonly seen in recent post-mortem cases, probably due
to prescribing trends. In all but one of the cases, other drugs or alcohol were present. However,
mirtazapine overdosage appeared to be a significant factor in at least half of the deaths reported and were
associated with a parent blood mirtazapine concentration >2.0 mgIL and a ratio of mirtazapine to
normirtazapine >2.
Keywords: blood, mirtazapine, postmortem
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