A careful drug history should be obtained from all patients with acute or chronic urticaria/angioedema, especially in the elderly. Although strictly comparable data are lacking, drug-induced urticaria appears to be more common in developed countries than in Malaysia, at least in a Hospital setting. Culprit drugs include antibiotics, analgesics and contrast media. Pseudoallergic drug-induced urticaria mimicks true allergic urticaria, but without an evident immunological basis, and is at least as common as the allergic type. In Malaysia, and in many other countries compulsory, ingredient labelling of 'traditional' medicines would do much to reduce the frequency of drug-induced urticaria.
We report a case in a young man who developed acute, persistent and painful tongue protrusion followed by swelling for more than 24 hours. He had relapse symptoms of schizophrenia and had recently received a single dose of parenteral haloperidol to manage his agitation. His record showed history of similar event and he has been taking atypical antipsychotic for maintenance. Mental state examination on admission revealed an agitated man with disorganised speech, restricted affect, auditory hallucination and persecutory delusion. His dystonia and oedema improved after 3 days. His mental status also recovered with the maintenance of low-potency antipsychotic and anticholinergic antiparkinsonian medications.