Definition of pentobarbital in US English:


(British pentobarbitone)


  • A narcotic and sedative barbiturate drug formerly used to relieve insomnia.

    Alternative name: 5-ethyl-5-(1-methylbutyl)-barbituric acid; often used as the sodium salt (sodium pentobarbitone, Nembutal)

    • ‘In this experiment, human volunteers consistently underestimated their performance impairment after acute administrations of triazolam, but not pentobarbital, a barbiturate.’
    • ‘Barbiturates, such as mephobarbital and pentobarbital sodium, which are used to treat anxiety, tension, and sleep disorders.’
    • ‘The sheep were given a general anaesthetic by intravenous pentobarbitone, intubation and ventilation.’
    • ‘To induce a coma, an anesthesiologist typically infuses a patient with increasing doses of the barbiturate pentobarbital while monitoring her brain waves with electrodes.’
    • ‘One drug in particular, sodium pentobarbital - a barbiturate used to euthanize animals - is of prime concern.’


1930s: from pentane + barbitone (or barbital).