Sodium Pentothal
Definition
Sodium thiopental, an ultra-short-acting barbiturate; intravenous infusion at a slow drip lowers cortical inhibition and is the standard agent for narco-analysis.
- Chemical name
- Sodium thiopental
- Drug class
- Ultra-short-acting barbiturate
- Route of administration
- Slow intravenous drip
- Forensic application
- Narco-analysis
Common questions
How does sodium pentothal produce the effect used in narco-analysis?+
As a barbiturate, it depresses central nervous system activity, and at a carefully titrated sub-anaesthetic dose it lowers cortical inhibition, the theory being that a subject becomes less able to consciously fabricate or withhold information while under its influence.
Is evidence obtained through narco-analysis with sodium pentothal admissible in court?+
Its admissibility is heavily contested and varies by jurisdiction; many courts treat statements made under its influence as unreliable or as raising self-incrimination and consent concerns, so it is generally used, where permitted, as an investigative lead rather than as direct courtroom evidence.
Why is 'slow drip' administration emphasised rather than a single injection?+
A slow, controlled infusion lets the administering physician titrate the dose to keep the subject in the narrow window between full consciousness and unconsciousness. A rapid or excessive dose risks over-sedation, respiratory depression, or simply putting the subject to sleep, defeating the purpose.
Related terms
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- Brain Electrical Oscillation Signature profiling, developed by Champadi Raman Mukundan and validated 2003 at NIMHANS Bangalore; uses 32-channel EEG to classify probes...
- CQT
- Control Question Test (Reid/Keeler technique): compares physiological response to relevant questions with response to control (probable-lie) questions; the dominant US polygraph format.
- Criminal Profiling
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- FBI BAU
- Behavioral Analysis Unit at the FBI Academy, Quantico, evolved from the Behavioral Science Unit set up by Howard Teten and Pat Mullany...
- GKT / CIT
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- Modus Operandi
- How the offender commits the crime: the functional behaviour needed to complete it; evolves with experience and feedback.
- Narco-Analysis
- A technique in which a subject is administered a barbiturate or benzodiazepine drug (commonly sodium pentothal or midazolam) to induce a hypnotic...
- Organised vs Disorganised
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- P300
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- Polygraph
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- Signature
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