Encyclopedia of Health and Medicine

B
THE TRUTH ABOUT TRUTH SERUM
Thiopental, better known by its trade name Pentothal,
is a fast-acting barbiturate that produces a
trancelike state of semiconsciousness. One effect
of this state is the blockade of inhibition, allowing
a person to do and say what the conscious
mind might block. Psychiatrists first used sodium
pentothal expressly for this purpose when treating
what was then called battle fatigue in soldiers
returning from World War II. Psychiatrists
were able to learn the details of the traumatic
experiences the soldiers endured and provide
therapy to help them cope with their memories.
However, a person under Pentothal’s influence
does not necessarily answer questions truthfully
and indeed may sometimes tell lies once the
effect of medication removes the inhibition that
would otherwise prevent him or her from doing
so.
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barbiturates DRUGS that depress the functions of
the CENTRAL NERVOUS SYSTEM. Barbiturates are
SCHEDULED DRUGS in the United States, requiring a
physician’s prescription for legal use and possession.
Some barbiturates are schedule 2 drugs,
which strictly limits the reasons for which physicians
may prescribe them.
Barbiturates readily cross the BLOOD–BRAIN BAR-
RIER once in the BLOOD circulation and act similarly
to ALCOHOL in the ways they affect BRAIN neurons.
Though researchers do not know the precise
mechanisms through which barbiturates alter
brain function, they believe these drugs cause
changes in the cell membranes of neurons in a
way that alters their action potential (ability to
transmit electrical impulses). Researchers do know
barbiturates also potentiate (enhance) the presence
and activity of gamma aminobutyric acid
(GABA), a NEUROTRANSMITTER that regulates many
of the brain’s inhibitory functions.
Excessive amounts of barbiturates in the blood
circulation suppress the respiratory centers in the
brain. Barbiturates also slow HEART RATE and lower
BLOOD PRESSURE. Combining barbiturates with alcohol
is particularly hazardous, as these drugs act in
the same ways to depress neurologic function.
Barbiturate OVERDOSE is life threatening
and requires emergency medical care.
Signs of barbiturate overdose include
UNCONSCIOUSNESS, dilated pupils, shallow
BREATHING, and slow PULSE.
Barbiturates have numerous therapeutic uses,
including sedation during diagnostic and minor
surgical procedures, suppression of seizures, and
relief of severe anxiety. However, because barbiturates
have high potential for ADDICTION and abuse,
they are seldom the first line of therapy for most
conditions except certain seizure disorders. As
drugs of abuse barbiturates are popular for the
sense of calm and well-being they can provide and
their effectiveness to induce sleep.
amobarbital
butabarbital
mephobarbital
pentobarbital
secobarbital
COMMON BARBITURATES
aprobarbital
butalbital
methohexital
phenobarbital
thiopental
Suddenly stopping barbiturates after long-term
use can result in serious or lethal complications,
resulting from neurotransmitter imbalance in the