Eleanor M. Kellon, VMD and Kathleen M. Gustafson, PhD
Interest in the therapeutic use of canagliflozin and ertugliflozin (brand names, Invokana and Steglatro, respectively) has been rapidly increasing. (1,2) This class of drugs, known as SGLT2 inhibitors, act to effectively lower glucose and insulin in horses with equine metabolic syndrome (EMS) or hyperinsulinemia associated with pituitary pars intermedia dysfunction (PPID; aka Cushing’s disease) that do not respond to diet management, e.g., lowering the intake of simple sugars and starch that induce a glycemic and insulinemic response, However, there are several important considerations that owners and their treating veterinarians should consider before use:
- These drugs are not a substitute for a safe, low-carbohydrate diet (simple sugar and starch content less than 10%).
- If the horse has PPID, ACTH must be controlled with medication.
- It is prudent to check complete blood chemistry and serum triglycerides before starting and periodically while on the drug.
- There are significant potential urinary tract complications from increased glucose in the urine and kidney injury if the animal is receiving NSAIDs, e.g., phenylbutazole or firocoxib.
- There is a very high probability that triglyceride levels will increase (1). Uncontrolled high triglycerides can lead to fatty liver.
- Dietary modifications can help control triglycerides.
- The animal can easily become dehydrated from the increased urine output, increasing the risk of colic. Assure that salt intake is adequate. Supplement at least 2 Tablespoons/day of plain salt in cool weather.
For over 3 years, the non-profit Equine Cushing’s and Insulin Resistance Group (ECIR Group Inc.) has been monitoring the case histories provided by owners whose veterinarians have prescribed these drugs. (https://ecir.groups.io/g/main) These cases histories provided data for one published report (2) and another documenting the incidence of elevated triglycerides (under review).
These warnings are important. The drugs are highly effective in reducing glucose and insulin, but their use requires understanding of the risks and how to prevent or reduce potentially dangerous side effects. Owners and veterinarians who would like to have more detailed information can contact Dr. Kellon at drkellon@gmail.com
- Sundra, T., Kelty, E. & Rendle, D. (2022) Preliminary observations on the use of ertugliflozin in the management of hyperinsulinaemia and laminitis in 51 horses: A case series. Equine Veterinary Education, 00, 1– 10. Available from: https://doi.org/10.1111/eve.13738
- Kellon, E. M. and Gustafson, K. M. (2022) Use of the SGLT2 inhibitor canagliflozin for control of refractory equine hyperinsulinemia and laminitis. Open Vet J., 12:511-518. PMID: 36118716. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9473365/
About ECIR Group Inc.
Started in 1999, the ECIR Group is the largest field-trial database for PPID and EMS in the world and provides the latest research, diagnosis, and treatment information, in addition to dietary recommendations for horses with these conditions. Even universities do not and cannot compile and follow long term as many in-depth case histories of PPID/EMS horses as the ECIR Group.
In 2013 the Equine Cushing’s and Insulin Resistance Group Inc., an Arizona nonprofit corporation, was approved as a 501(c)3 public charity. Tax deductible contributions and grants support ongoing research, education, and awareness of Equine Cushing’s Disease/PPID and EMS.
THE MISSION of the ECIR Group Inc. is to improve the welfare of equines with metabolic disorders via a unique interface between basic research and real-life clinical experience. Prevention of laminitis is the ultimate goal. The ECIR Group serves the scientific community, practicing clinicians, and owners by focusing on investigations most likely to quickly, immediately, and significantly benefit the welfare of the horse.
Contact: Nancy Collins
603-323-7469
ecirgroup1@gmail.com
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