ALTERATIONS IN RESPONSE TO SOMATIC PAIN ASSOCIATED WITH ANAESTHESIA XIII: THE "LYTIC COCKTAIL"

SUMMARY Analgesimetry readings were carried out following the intravenous injection of varying doses of a mixture of pethidine (2 parts), chlorpromazine (1 part) and promethazine (1 part), which is commonly known as the "lytic cocktail". This produced an immediate increased sensitivity to somatic pain, followed by a prolonged period of analgesia. This may be due to the earlier onset of action of promethazine (antanalgesia) as compared with pethidine (analgesia) and a biphasic effect of chlorpromazine. Hypotension was a common finding with this mixture and its severity and duration was such as to outweigh any advantages it might have for use in premedication.