Eosinophil-associated gastrointestinal disorders (EGIDs), including eosinophilic 
esophagitis (EE) and eosinophilic gastroenteritis (EG), are a spectrum of 
increasingly recognized inflammatory diseases characterized by gastrointestinal 
symptoms and eosinophilic infiltration of the gastrointestinal tract. 
Significant morbidity is associated with the development of esophageal 
strictures in some patients. Immune-mediated reactions to food allergens appear 
to drive the inflammation in a subset of patients, especially those with 
solitary EE, but dietary interventions remain difficult in EE and are less 
effective in EG. Despite the increasing incidence of these disorders and their 
increased recognition by physicians, there are currently no medications that 
either United States or European Union regulatory agencies have specifically 
approved for use in EGIDs. This lack of safe and effective therapies for EGIDs 
is a major obstacle in the care of these patients and underscores the need for 
new therapeutic approaches. This review briefly discusses the currently 
available 'off label' drug treatments for EGIDs, most notably topical and 
systemic corticosteroids. Pathogenesis studies of EGIDs suggest possible 
therapeutic targets, and conversely, clinical trials of mechanistically-targeted 
therapeutics give insight into disease pathogenesis. Thus, EGID pathogenesis is 
discussed as an introduction to mechanistically-targeted immunotherapeutics. The 
two biologic categories that have been used in EGIDs, anti-IgE (omalizumab) and 
anti-IL-5 (SCH55700/reslizumab and mepolizumab), are discussed. Because there 
are similarities in the pathogenesis of EGIDs with asthma and atopic dermatitis, 
biologic therapeutics currently in early trials for asthma management are also 
briefly discussed as potential therapeutic agents for EGIDs. Given the 
deficiencies of current therapeutics and the rapidly advancing knowledge of the 
pathogenesis of these disorders, EGIDs are an ideal model for translating recent 
advances in understanding immunopathogenesis into mechanistically-based 
therapeutics. Further understanding of the early events in pathogenesis is also 
needed to develop preventive and disease-modifying treatments.