Hamdard Medicus Vol. 58, No. 1, 2015 5 A Contemporary Review on Eosinophilia Mursaleen Naseer Department of Moalejat, Ajmal Khan Tibbiya College, Faculty of Unani Medicine, Aligarh Muslim University, Aligarh-202002, India. It was believed that in classical Unani text that there was no concept of eosinophilia in the ancient time. On the contrary, while going through the Unani literature, it was revealed that renowned Unani scholars have described certain diseases like Zeequn Nafas (Asthma), Deedan-e-Ama (Intestinal Worms), Daulfeel (Elephantiasis), Nar-e-farsi (Eczema) and Jarb (Scabies) in their treatises, which are well known causes of eosinophilia. Moreover, there are some conditions namely Sual (cough), Attas (Sneezing), Hikka (Pruritus), Hikkaul unf (Nasal itching) and Shara (Urticaria), which reflect the concept of allergen in their etiology and management. The invention of microscope played the vital role in the discovery of eosinophils. Thus, diseases which have been described since antiquity mimic with the eosinophilia, and a stepwise progression in knowledge has led to the present era as a well known clinical entity viz. Eosinophilia. Keywords: Unani, Eosinophils, Eosinophilia, Review. Eosinophilia refers to an increase in the number of eosinophilic leucocytes above normal (>0.7x10 9 /L) levels if calculated from the total leucocyte and differential count and more than about 0.2x10 9 /L if determined by absolute counting methods 1 . The life span of eosinophils is much longer than neutrophils, and unlike neutrophils tissue eosinophils can re-circulate too. During most infections, eosinophils are not important. However, in invasive helminthic infestations, such as hookworm, schistosomiasis, strongyloidiasis, toxocariasis, trichinosis, filariasis, echinococcosis, and cysticercosis, they play a central role in host defence. And also associated with bronchial asthma, cutaneous allergic reactions, and other hypersensitivity states 2 . Since last three decades there has been renewed interest in the eosinophil related diseases mainly due to the advancement to conduct