Heart disease in reptiles remains infrequently reported in the veterinary literature, as do successful treatments.1–6 Congestive heart failure has been diagnosed in snakes, chelonians, and lizards.7–10,a Related clinical findings are generally nonspecific, including anorexia, lethargy, peripheral edema, ascites, cyanosis, dyspnea, exophthalmos, blepharedema, and sudden death, and can be attributable to congestive heart failure.2,8,a Many reptiles identified with heart disease are subsequently euthanized or do not survive to treatment.2,a
Diuretics such as furosemide are a mainstay of cardiac disease treatment for humans and other animals, with the aim of reducing fluid overload, edema, and effusion.11 In mammals, furosemide administration reduces reabsorption of sodium and chloride in the renal loops of Henle, thereby leading to increased excretion of water from the kidneys.12 In reptiles, use of furosemide is controversial, given that reptiles have metanephric kidneys that lack the loop-of-Henle structure and, therefore, are unable to produce hypertonic urine.13 However, in chelonians and snakes, furosemide produces diuresis by altering renal tubular electrolyte absorption and renal excretion.14–17 In addition, postrenal diuretic effects of furosemide have been reported for lizards and turtles.18,19 Clinical reports describe the use of furosemide in reptiles (lizards, snakes, and a tortoise) with congestive heart failure at dosages ranging from 1 to 15 mg/kg every 6 to 48 hours, with inconsistent results.2,9,a In loggerhead sea turtles (Caretta caretta) with brevetoxicosis, furosemide (5 mg/kg, IM, q 24 h) has been successfully used to maintain dehydration and, thereby, aid in recovery.20
The purpose of the study reported here was to evaluate the diuretic effects of and associated changes in hematologic and plasma biochemical values following furosemide administration to inland bearded dragons (Pogona vitticeps) by measuring body weight, PCV, plasma biochemical variables, and water consumption before and after furosemide treatment. It was hypothesized that SC furosemide administration would produce a diuretic effect, therefore leading to clinically measurable changes, reflected in body weight, plasma biochemical concentrations, and osmolarity in water-deprived bearded dragons.
Supported by the University of Wisconsin School of Veterinary Medicine Companion Animal Fund, the Association of Reptile and Amphibian Veterinarians, and Abaxis Global Diagnostics Inc.
Simone-Freilicher E, Sullivan P, Quinn R, et al. Two cases of congestive heart failure in lizards, in Proceedings. 1st ExoticsCon 2015;505–509.
Orange Cube cricket diet, Hi-Calcium cricket diet, and Cricket Quencher with calcium, Fluker Farms, Port Allen, La.
Salix, Merck Animal Health, Kenilworth, NJ.
Pro-Vent, Smiths Medical Inc, Keene, NH.
VetScan Avian/Reptile Profile Plus, Abaxis Inc, Union City, Calif.
Advanced micro-osmometer model No. 3300, Advanced Instruments Inc, Norwood, Mass.
SigmaPlot, version 13, Systat Software, San Jose, Calif.
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