Thiopental Health Dictionary

A group of sedative drugs that work by depressing activity within the brain. They include thiopental and phenobarbital. In the past, barbiturates were widely used as antianxiety drugs and sleeping drugs but have been largely replaced by benzodiazepine drugs and other nonbarbiturates. Barbiturates are now strictly controlled because they are habit-forming and widely abused. An overdose can be fatal, particularly in combination with alcohol, which dangerously increases the depressant effect on the brain (including suppression of the respiratory centre). However, phenobarbital is still commonly used as an anticonvulsant drug in the treatment of epilepsy. Thiopental is very short acting and is used to induce anaesthesia (see anaesthesia, general).... barbiturate drugs

1. n. an agent that reduces or abolishes sensation, affecting either the whole body (general anaesthetic) or a particular area or region (local anaesthetic). General anaesthetics, used for surgical procedures, depress activity of the central nervous system, producing loss of consciousness. *Anaesthesia is induced by intravenous anaesthetics, such as *thiopental, etomidate, or propofol, and maintained by inhalation anaesthetics (such as *sevoflurane). Local anaesthetics inhibit conduction of impulses in sensory nerves in the region where they are injected or applied; they include *tetracaine, *bupivacaine, and *lidocaine. 2. adj. reducing or abolishing sensation.... anaesthetic

n. any of a group of drugs, derived from barbituric acid, that depress activity of the central nervous system and were formerly widely used as sedatives and hypnotics. They are classified into three groups according to their duration of action – short, intermediate, and long. Because they produce *tolerance and psychological and physical *dependence, have serious toxic side-effects (see barbiturism), and can be fatal following large overdosage, barbiturates have been largely replaced in clinical use by safer drugs. The main exception is the very short-acting drug *thiopental, which is used to induce anaesthesia. See also amobarbital; butobarbital; phenobarbital.... barbiturate

n. 1. (in obstetrics) the starting of labour by artificial means. It is carried out using such drugs as *prostaglandins to prime the cervix and/or *amniotomy prior to synthetic *oxytocin (Syntocinon), which stimulate uterine contractions. Induction of labour is carried out if the wellbeing or life of mother or child is threatened by continuance of the pregnancy. 2. (in anaesthesia) initiation of *anaesthesia. General anaesthesia is usually induced by the intravenous injection of short-acting *anaesthetics, e.g. thiopental.... induction