Isoflurane is a general inhalation anaesthetic which provides rapid induction of anaesthesia and rapid recovery. In common with all inhalational anaesthetics, isoflurane induces a dose-dependent depression of central neural activity and cerebral metabolism, while cerebrospinal fluid pressure may increase due to cerebral vasodilatation. Isoflurane causes a dose-dependent depression of breathing and a decreased ventilatory response to carbon dioxide. The decrease of blood pressure which occurs during isoflurane anaesthesia is predominantly due to peripheral arterial and venous dilatation, whereas heart rate and cardiac output are well maintained up to maintained inspiratory concentrations of 2.5%. Isoflurane, which has minimal effects on atrioventricular conduction, causes significantly less sensitisation of the heart to the arrhythmic effects of catecholamines than does halothane. Isoflurane shows very low solubility in blood and body tissues, much lower than for enflurane and halothane. This low solubility results in a rapid development of an alveolar pressure sufficient to cause anaesthesia.