Serum Eye Drops for Ocular Surface Disease in Veterinary Ophthalmology: A Translational Review of Human and Veterinary Evidence

BACKGROUND: Serum closely resembles natural tears in composition and contains higher growth factor levels than plasma in humans. Beyond its well-established anticollagenase properties, evidence from human ophthalmology suggests a broader therapeutic potential that may extend to the management of ocular surface diseases in animals. OBJECTIVES: This review examines the composition, mechanisms, and clinical applications of serum eye drops (SEDs) in human and veterinary ophthalmology, compares serum with plasma, and proposes a protocol for their formulation. RESULTS: -macroglobulin). Key human indications include dry eye disease and persistent epithelial defects. In veterinary patients, SEDs are primarily used for keratomalacia, with additional potential applications-such as non-healing ulcers, neurotrophic and herpetic keratitis, chemical injuries, toxic keratopathy, and keratoconjunctivitis sicca-though evidence remains limited and largely extrapolated from human studies. Optimal preparation involves 120-min clotting, centrifugation at 3000×g, and optional dilution with saline, BSS, or sodium hyaluronate. Refrigerated storage (4°C) for up to 7 days is supported for canine serum, and at -20°C for 6 months, though stability of some components may vary. Aseptic handling, single-patient use, and refrigeration minimize contamination. SEDs are well tolerated, with few adverse effects reported in humans and none yet in veterinary patients. CONCLUSIONS: SEDs offer physiologically rational adjunctive therapy for OSD in animals. Although serum and plasma have similar antiprotease activity, serum may promote better epithelial healing. Further veterinary studies are warranted.