Failure to prevent an anaphylactic reaction to a second neuromuscular blocking drug during anaesthesia.

Skin testing is used widely to determine the drug responsible for an anaphylactic reaction during anaesthesia. When a neuromuscular blocking drug in incriminated as the cause of a reaction, it is usual for neuromuscular blocking drugs which do not produce positive skin tests to be considered safe for subsequent use during anaesthesia. We describe three patients in whom false negative skin tests led to a second severe anaphylactic reaction to another neuromuscular blocking drug.