With conjunctivitis, plasma constituents tend to “leak” into the tear compartment as the permeability of conjunctival vessels is typically increased.10,11 This breakdown of the blood–tear barrier explains the large quantities of albumin in tears of diseased eyes, regardless of the underlying etiology of conjunctivitis (eg, dry eye, corneal ulcer, allergies).24,25 Thus, to make the present PK findings more clinically relevant, conjunctivitis was experimentally induced in selected canine eyes using a recently described model.11 The gene discussed is ALB; the disease is Keratoconjunctivitis sicca.