Page 31 - Advances in Forensic Applications of Mass Spectrometry - Jehuda Yinon

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available. Screening for and identification of these drugs can be performed
by GC/MS (acid hydrolysis, LLE, and AC). 58,223,224 Chloral hydrate, the hydrate
of trichloroacetaldehyde, is still used as a sedative–hypnotic, especially in
pediatrics. Trichloroethanol is the main pharmacologically active principle
of chloral hydrate therapy, and should therefore be included in the analysis.
The usual screening procedures do not cover chloral hydrate or trichloroeth-
anol. Therefore, the Fujiwara reaction for halogenated hydrocarbons is rec-
225
ommended as a qualitative test. However, only chloral hydrate itself leads
to the red reaction product, whereas the main metabolite, trichloroethanol,
produces only a yellow color which cannot be differentiated from typical
urine color. Chloral hydrate and/or trichloroethanol can be determined in
urine or plasma by simple GC/MS. 226–228 Further procedures for seda-
tive–hypnotics were reviewed by Kraemer and Maurer. 229

1.4.1.1.9 Antidepressants. Tricyclic antidepressants (TCA), monamine
oxidase inhibitors, and/or the newer selective serotonin reuptake inhibitors
(SSRIs) are in use for the pharmacotherapy of depression. Among these, the
SSRIs are less toxic since they do not show significant noradrenergic or anti-
cholinergic properties. However, even if they are considered to be safe and well
tolerated, they may multiply — by inhibition of cytochrome P450 metabolism
— the pharmacological and toxic effects of other drugs like TCAs or anticon-
vulsants. 230,231 Therefore, they may be encountered in clinical and forensic
cases. Methods for quantification have been reviewed. 232–234 In addition,
immunoassays are available, but due to different cross-reactivity and potency,
the TCA taken must be identified before calculation of the plasma level. There-
fore, a systematic toxicological screening must cover these drugs. 58,59,235

1.4.1.1.10 Neuroleptics of the Phenothiazine and Butyrophenone
Type. Neuroleptics (phenothiazines, butyrophenones, and atypics) have
suppressing effects on the consciousness and the respiration. Most exhibit
anticholinergic effects in the autonomic nervous system. As overdosage may
lead to severe poisonings, fast diagnosis is required. Immunoassays are not
available, so screening must be performed directly by GC/MS. 1,58,236 Only
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risperidone cannot be detected by GC/MS; LC/MS is required. Screening,
library-assisted identification, and validated quantification of fifteen neu-
roleptics and three of their metabolites in plasma have recently been
described using LC/MS with atmospheric pressure chemical ionization. 22

1.4.1.1.11 Antihistamines (Histamine H -Receptor Blockers). Block-
1
ers of the histamine H -receptor (antihistamines) are used as allergy reme-
1
dies, nonprescription hypnotics, and in combination with other drugs such
as cold medicines. Antihistamines, often combined with other drugs or

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