Anti-inflammatory Drugs in Equine Neonatal Medicine. Part II: Corticosteroids

•Coricosteroids are used in a variety of clinical settings in foals.•There are few studies about the use of glucocorticoids in equine neonatology.•Dexamethasone pharmacokinetics and pharmacodynamics have not been studied in foals.•Hydrocortisone has been studied in neonatal healthy foals.

In equine neonatology, corticosteroids are used to treat conditions such as acute adrenal insufficiency, relative adrenal insufficiency, or critical illness–related corticosteroid insufficiency that occurs in critically ill and septic foals, septic shock and prematurity, neonatal isoerythrolysis, immune-mediated thrombocytopenia, acute lung injury or acute respiratory distress syndrome, and immune-mediated hemolytic anemia, which have been reported in both neonate and older foals. Dexamethasone is one of the commonly used glucocorticoids in equine neonatology practice. To the authors' knowledge, the pharmacokinetics and pharmacodynamics of dexamethasone administered PO or IV have never been investigated in neonatal foals notwithstanding its large use in a variety of clinical settings. Hydrocortisone is the pharmaceutical term for cortisol, the principal glucocorticoid secreted by the adrenal gland. The effect of a low-dose hydrocortisone (LDHC) therapy on immune function in neonatal healthy foals has been studied, and its administration has been shown to ameliorate a detrimental proinflammatory response in septic neonates without impairing innate immune and endocrine responses to infections. Further studies are needed to evaluate the effects of LDHC therapy in the equine neonates in a clinical setting. Given the number and severity of potential side effects and the absence of an evidence-based equine neonatal pharmacotherapy, the decision to institute therapy with corticosteroids requires a careful consideration of the risks and benefits especially in critically ill foals.