Forensic Pathology for Police - Brainshare Public Online Library

Cocaine 275
Barbiturates
Barbiturates are a group of depressant drugs, commonly referred to as “downers.”
Other street names include “redbirds,” “blue heavens,” “goofballs,” and “yellow
jackets.” There are three basic groups, depending on their timing of onset and
duration of action (short-acting, intermediate-acting, and long-acting). The drugs
are typically ingested or injected and have a sedative-hypnotic effect. Overdose
results in coma and death. Medicinally, they are frequently used in anesthesia or
as anticonvulsants. Examples include phenobarbital, secobarbital, amobarbital, and
pentobarbital.
Although barbiturate abuse has fallen out of favor, occasional overdoses are still
encountered. Classic descriptions of some of the lesions associated with barbiturate
abuse include the presence of “barbiturate blisters” on the skin, necrosis (death)
of a particular structure in the brain referred to as the “globus pallidus,” and the
identification of polarizable crystals seen under the microscope when looking at the
stomach lining (if the drug was ingested). The latter finding is not specific to barbiturates,
as it can be seen with numerous ingested drugs. The term “drug automatism”
refers specifically to the prolonged uncontrollable intake of barbiturates.
Cocaine
Cocaine is produced from a plant called Erythroxylon coca. It has legitimate medicinal
use as a local anesthetic agent, usually in facial-type surgery, but is far more
commonly a drug of abuse. It is considered a stimulant, primarily affecting the CNS
and cardiovascular systems. It acts in the nervous system by inhibiting the reuptake
of the neurotransmitters dopamine and norepinephrine. It may be injected, insufflated
(snorted), smoked, ingested, or applied topically. Cocaine hydrochloride is
the powder form of the drug, and is sometimes referred to as “soft” cocaine. “Rock”
cocaine is a very pure form of cocaine hydrochloride. “Crack”, or free-base cocaine,
is smoked (Fig. 11.19), and is sometimes referred to as “hard” cocaine. Cocaine
Fig. 11.19 Crack cocaine discovered in the pocket of a homicide victim