Anaphylactoid reaction to vecuronium followed by systemic reaction to skin testing

An unusual case is presented of a systemic anaphylactoid reaction to tubocurarine and subsequently to vecuronium. Intradermal testing with vecuronium following the latter response was negative at recommended test dose levels but at a higher concentration it initiated a hazardous systemic response. The laboratory investigations and possible mechanisms involved in this unusual case are discussed in detail since they may relate to other patients who experience anaphylactoid responses to anaesthetic drugs and who then undergo intradermal testing.