Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 21 5 2022 10 26 494 511 Soheila Asoudeh Moghanloo Department of Genetics, Marvdasht Branch, Islamic Azad University, Marvdasht, Iran AND Immunology, Asthma and Allergy Research Institute (IAARI), Tehran University of Medical Sciences, Tehran, Iran Mohsen Forouzanfar Department of Genetics, Marvdasht Branch, Islamic Azad University, Marvdasht, Iran Mojtaba Jafarinia Department of Genetics, Marvdasht Branch, Islamic Azad University, Marvdasht, Iran Mohammad Reza Fazlollahi Immunology, Asthma and Allergy Research Institute (IAARI), Tehran University of Medical Sciences, Tehran, Iran Gholam Ali Kardar Immunology, Asthma and Allergy Research Institute (IAARI), Tehran University of Medical Sciences, Tehran, Iran AND Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran 2022 03 13 2022 07 05 Allergen-specific immunotherapy (AIT) involves administering allergen extracts. It is used to desensitize allergic patients. Herbal allergen extracts that are optimum in efficacy and fewest in side effects are still challenging to produce. To overcome these limitations, oral immunotherapy, epicutaneous immunotherapy, intralymphatic immunotherapy, and artificial recombinant allergen preparations have been evaluated. Recombinant allergens have become more popular with the development of molecular diagnostics and therapeutics. Besides food and drug allergens, pollen, fungal spores, and other allergens have been studied. Based on related clinical studies, this comprehensive overview will present the latest perspectives on AIT methods and available allergenic products, as well as discuss the challenges and opportunities for treating allergic disorders. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/3481 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/3481/1886