IL4 and allergic asthma: Additionally, in an in vivo study of ovalbumin-instigated allergic asthma, eugenol reduced ovalbumin-specific IgE levels, as well as interleukin-4 and -5 (IL-4 and-5), the primary cytokines in various types ofallergic reactions, preventing the emergence of a Th2-type immune response [133,134].