-
Propofol
- indication:Used for induction and/or maintenance of anaesthesia and for management of refractory status epilepticus.
- pharmacologypharmacology:
- mechanism: The action of propofol involves a positive modulation of the inhibitory function of the neurotransmitter gama-aminobutyric acid (GABA) through GABA-A receptors.
- toxicity: Overdosage may increase pharmacologic and adverse effects or cause death. <p>IV LD<sub>50</sub>=53 mg/kg (mice), 42 mg/kg (rats). Oral LD<sub>50</sub> (as a solution in soybean oil)=1230 mg/kg (mice), 600 mg/kg (rats)</p>
- absorprion: Rapid - time to onset of unconsciousness is 15-30 seconds, due to rapid distribution from plasma to the CNS. Distribution is so rapid that peak plasma concentrations cannot be readily measured. Duration of action is 5-10 minutes.
- halflife: Initial distribution phase t<sub>1/2&alpha;</sub>=1.8-9.5 minutes. Second redistirubtion phase t<sub>1/2&beta;</sub>=21-70 minutes. Terminal elimination phase t<sub>1/2&gamma;</sub>=1.5-31 hours.
- roouteelimination: It is chiefly eliminated by hepatic conjugation to inactive metabolites which are excreted by the kidney.
- volumedistribution: * 60 L/kg [healthy adults]
- clearance: * 23 - 50 mL/kg/min * 1.6 - 3.4 L/min [70 Kg adults]