Adverse reaction to dental local anaesthetic injection - 'allergy' is not the cause

Objective To investigate patients considered to have experienced allergic r eactions to local anaesthetics administered for dental treatment. Setting Dental facility within a general hospital. Procedure Skin and intra-oral challenge tests. Results No patients were found to be allergic to lignocaine or prilocaine. The most likely causes of the adverse reactions were found to be psychogeni c. Conclusion Although allergy to lignocaine (and the other amide anaesthetic agents used in dentistry) is known to be extremely rare, it continues to be suggested as a cause when adverse reactions to dental injections occur. Ps ychogenic reactions are the main causes of untoward events, and some can be alarming. A smaller proportion of adverse responses can be attributed to ( avoidable) intravascular injections. Adverse reactions can be reduced if in jections are administered carefully.