- Sulphur analogue of pentobarbital - it is a thiobarbituate.
- Yellowish powder with a bitter taste and a faint smell of garlic (cheese & onion!)
Although it is highly protein-bound (80%), its high lipid solubility and high non-ionized fraction (60%) accounts for rapid brain uptake within 30 s
2.5 - 4.5mg/kg IV induction
Undergoes hepatic oxidation at 10-15%/hr with 30% left at 24hHangover effect due to this long metabolism and cumulates if second dose given
- Increased HR
- Reduced Contractility
- due to drop in MAP & CO (baroreceptor)
In patients with intravascular volume depletion, low serum albumin,
or if the non-ionized fraction is increased (like in metabolic acidosis), higher concentrations within the brain and heart will be achieved for a given dose,
increasing the risk of cardiovascular compromise.
Cannot be used in acute intermittent porphyria
Anaphylactic and anaphylactoid reactions
Cardiovascular: Hypotension, myocardial depression, arrhythmias
Respiratory: Respiratory depression, coughing, bronchospasm and laryngospasm
Binds to the β sub- unit of the GABAa-chloride receptor complex.
Potent Anti-convulsant, Potent Hypnotic, Poor Analgesic
Can act as an antanalgesic/hyperalgesic
Dr. David Lyness@Gas_Craic