Abstract  Background: Chronic urticaria can be caused by a number of known and unknown allergens. Some of these allergens can be identified by prick tests. Objectives: To assess the positivity of skin prick test (SPT) in patients with chronic urticaria Patients and Methods: Forty patients diagnosed with chronic urticaria attending Skin department of our institute were included in the study and evaluated by prick testing. Results: Among the 40 patients, 33 patients showed positive reactions to various allergens tested i.e 82.5%. The mean age of the patients was 30 years. Female to male ratio was 1.6:1. On SPT, number of patients with 1-5 positive reactions were13, 6-10 were 15 and more than 10 were 5 patients. Ten most common allergens in order of their frequency include mite D-farinae (52), mite D-pteronyssinus (48), cockroach (32), prawn(28), housefly (25), chicken (22), cyanodon (22), parthenium (20),mosquito (20), crab (16). The five most common food allergen positivity include prawn (29%), chicken (24%), wheat (18%), crab (16%), black pepper(13%). Conclusions: A greater proportion of patients with chronic urticaria demonstrate sensitivity to house dust mites, cockroach, pollens along with food. Thus, SPT is an important diagnostic procedure in cases of chronic urticaria, It is also important to perform SPTs among patients suffering from chronic urticaria not only for food allergens but also for pollens, house dust mites.

Keywords: Urticaria, skin prick test, allergens, mites, insects, food.