Anaphylactic reaction to ranitidine.

Ranitidine is a well-tolerated H2-receptor antagonist with a furan ring as nucleus. Anaphylactic reactions are seldom reported despite the wide use of the drug. We report a patient who presented an anaphylactic reaction with ranitidine (Zantac). The positive skin prick test and oral challenge suggest type I hypersensitivity. Specific IgE determination by RAST technique and histamine release test with ranitidine were negative. The patient did not react to other H2-receptor antagonists or to another furan-derivative (nitrofurantoin).