Method of enhancing the activity of parentally administrable drugs

摘要

Injectable compositions comprise a sterile mixture of a liquid carrier, a parenterally administrable drug, and from 0.1 to 10% (by weight of the drug) of a surface active agent selected from quaternary ammonium compounds, sulphosuccinates, polyoxyethylene condensates of long chain alkanols and their sulphuric acid monoesters, alkylated phenoxyethanols, and alkylated phenoxy (polyethanols), the drug being defined as one which acts at a site protected by a complex lipid barrier layer (e.g. at the surface of nerve tissue). Specified drugs of this type are adrenalin, nor-adrenalin, curare (i.e. tube or bamboo curare, pot curare, and gourd or calabash curare), lidocaine, serotonin and digitoxin. Preferred surface active agents are compounds of the formula: where R is C1 to C18 alkyl, particularly nonyl or octyl, and n has an average value of 1 to 30, particularly 6 when R is nonyl and 9 to 10 when R is actyl. Carriers may be buffered isotonic aqueous solutions, sesame or peanut oil, aqueous propylene glycol or N,N-dimethyl-formamide. The compositions may be sterilised by filtration. The surface active agent is said to enhance the activity of the drug, and the invention includes a method for such enhancement wherein the drug and surface active agent are parenterally administered to warm blooded animals excluding human beings, either simultaneously and preferably together as a composition, or separately (e.g. up to 15 minutes apart) so that the surface active agent is present in the animal body during the period of activity of the drug. Examples are given for this method, using Triton X-100 (Registered Trade Mark) and similar compounds as the surface active agent.