Ophthalmic corticosteroid therapy: systemic effects in the dog
Glaze, M.B.; Crawford, M.A.; Nachreiner, R.F.; Casey, H.W.; Nafe, L.A.; Kearney, M.T.
Journal of the American Veterinary Medical Association 192(1): 73-75
1988
ISSN/ISBN: 0003-1488 PMID: 3343186 Document Number: 323312
Degenerative myopathy suggestive of glucocorticoid-induced myopathy was diagnosed in a 10-year-old female PoodleXPekingese dog with a history of progressive lameness. Electromyography revealed unusual high-frequency discharges. Evidence of adrenal suppression was obtained in response to exogenous ACTH. The predominant source of corticosteroid was an ophthalmic preparation used in the management of keratoconjunctivitis sicca. Considering the apparent adverse effects of the corticosteroid in this case, a study was undertaken to determine the systemic effects, if any, induced by long-term ophthalmic administration of 0.1% dexamethasone suspension in healthy adult dogs. Dogs in one group (n=5) were treated 4 times daily for 8 weeks, and dogs in another group (n=5) were treated 4 times daily for 16 weeks. All dogs remained healthy throughout the study, but dexamethasone-treated dogs developed adrenal suppression, beginning the second week of treatment and throughout the treatment period. Histopathological changes in the liver of dexamethasone-treated dogs included scattered foci of vacuolated hepatocytes, increased hepatocytic glycogen content, and ballooning degeneration of hepatocytes. Muscle specimens were histologically, histochemically and electromyographically normal.