Biomedical Engineering Reference
In-Depth Information
mescaline is excreted as a glutamic conjugated acid after being subjected to hydrolysis
in the liver. In smaller quantities the metabolic processes lead to the formation of
N
-acetyl-mescaline and
N
-acetyl-3,4-dimethoxy-5-hydroxyphenetylammine [
21
] .
5.2
Dissociative Drugs of Abuse
Drugs such as phencyclidine and ketamine, the most important aryl-cyclohexane-
amine on the illicit market, were initially used as a general anesthetic in surgery: these
create distortions of sound and visual perception and feelings of dissociation from the
environment and from themselves. These mental changes are not hallucinations, so
phencyclidine and ketamine are more properly known as dissociative anesthetics. The
dissociative drugs act by altering the distribution of glutamate in the brain.
5.2.1
Phencyclidine
Phencyclidine (PCP) was developed in the 1950s as an intravenous anesthetic used
for surgical procedures. It has been used in veterinary but it then spread to the illicit
drug market. PCP is currently known by more than thirty names such as
angel dust
,
zoom
,
crystal cyclone
, and
peace
. In its pure form PCP is a white crystalline powder
that readily dissolves in water. It can be inhaled, smoked, injected, or chewed [
22
] .
Pharmacodynamics
PCP, like ketamine, targets a particular receptor site, located in the channel for cal-
cium, associated with excitatory amino receptors
N
-methyl- D -aspartate (NMDA)
located in the brain [
23
] .
Effects
PCP is able to alter the perceptual system up to the point of blocking its functioning,
leading to a sort of trance. Alterations of perception and mental status, associated with
the consumption of PCP, could also lead to difficulties in the articulation of language
and motor coordination, drowsiness, nausea, vomiting, temporary amnesia, hallucina-
tions, muscle spasms, convulsions, paralysis, and coma in severe forms.
Pharmacokinetics
PCP is metabolized in the liver and excreted through the urine. The main metabolic
pathway is hydroxylation. In urine, two metabolites were identified in the form of
