Katsiampoulas E. Medicine Unit, Companion Animals Clinic, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki
Dimitraki V. Medicine Unit, Companion Animals Clinic, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki
Konstantinidis A.O. Medicine Unit, Companion Animals Clinic, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki
Soubasis N. Medicine Unit, Companion Animals Clinic, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki
Komnenou A. Surgery-Comparative Opthalmology Unit, Companion Animals Clinic, Companion Animals Clinic, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki
Thomas A. L. Surgery-Comparative Opthalmology Unit, Companion Animals Clinic, Companion Animals Clinic, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki
Makri K. Medicine Unit, Companion Animals Clinic, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki
Zikopoulou I. Surgery-Comparative Opthalmology Unit, Companion Animals Clinic, Companion Animals Clinic, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki
Kakosimos L. Surgery-Comparative Opthalmology Unit, Companion Animals Clinic, Companion Animals Clinic, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki
Adamama-Moraitou K.K. Medicine Unit, Companion Animals Clinic, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki
Introduction
Ophthalmic solutions of carbonic anhydrase inhibitors (CAIs), most commonly dorzolamide, have been associated with hypokalemia in cats. In this study, a very rare case of severe hypokalemia, due to topical administration of the CAI brinzolamide eye drops 1% solution, is described.
Case Summary
A 2-year-old, neutered male, DSH cat was admitted with a 24-hour history of anorexia, depression and cervical ventroflexion. The cat had bilateral secondary glaucoma due to anterior lens luxation, receiving anti-glaucoma treatment with brinzolamide 1% ophthalmic solution. for the last 2 months. Cervical ventroflexion, generalized weakness, ataxia, depression, and mild dehydration were found upon physical examination. Clinicopathologic investigation revealed severe hypokalemia (2.4 mEq/ L). All other causes of hypokalemia were reasonably ruled out. Potassium deficits were replenished and topical administration of brinzolamide eye drops was discontinued permanently. The cat showed gradual improvement within 4 days.
Results
Hypokalemia was attributed to the topical administration of brinzolamide eye drops. After 6 months of follow up the cat remained in good clinical condition.
Conclusion
This case further underlines the association between the ophthalmic administration of CAI (especially brinzolamide) and the occurrence of potentially severe hypokalemia in cats. Therefore, careful monitoring of blood serum electrolyte profile is recommended in feline patients treated with these medications.
References
- Czepiel TM and Wasserman NT (2020) Hypokalemia associated with topical administration of dorzolamide 2% ophthalmic solution in cats. Veterinary Ophthalmology, 12–19.
- Thiessen CE, Tofflemire KL, Makielski KM, Ben-Shlomo G, Whitley RD and Allbaugh RA (2015) Hypokalemia and suspected renal tubular acidosis associated with topical carbonic anhydrase inhibitor therapy in a cat. Journal of Veterinary Emergency and Critical Care, 870–874.
- Kogika MM and de Morais HA (2008) Hypokalemia: A Quick Reference. Veterinary Clinics of North America: Small Animal Practice, 481–484.
- Farkouh A, Frigo P and Czejka M (2016) Systemic side effects of eye drops: a pharmacokinetic perspective. Clinical Ophthalmology, Volume 10, pp. 2433–2441.
