Effect of furosemide and high-dosage pimobendan administration on the renin-angiotensin-aldosterone system in dogs

Am J Vet Res. 2013 Aug;74(8):1084-90. doi: 10.2460/ajvr.74.8.1084.


Objective: To determine whether a high dosage of pimobendan, when administered concurrently with moderate-dosage furosemide to healthy dogs, would activate the renin-angiotensin-aldosterone system (RAAS) more than furosemide alone.

Animals: 12 healthy dogs.

Procedures: 6 dogs received furosemide (2.0 mg/kg, PO, q 12 h) only, as an RAAS activator, for 10 days. The other 6 dogs received furosemide (2.0 mg/kg, PO, q 12 h) and pimobendan (0.6 mg/kg, PO, q 12 h) for 10 days. The effect of these drugs on the RAAS was determined by measurement of the aldosterone-to-creatinine ratio (A:C) in urine collected in the morning and evening of study days -2, -1, 1, 5, and 10.

Results: Although there was an increase in the urine A:C during the study period in both groups, it was significant only for dogs that received both drugs. The urine A:C only differed significantly between groups on day 1, at which time A:C was greater in the group that received both drugs.

Conclusions and clinical relevance: High-dosage pimobendan administration neither substantially suppressed nor potentiated the RAAS when administered with furosemide in healthy dogs.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cardiotonic Agents / pharmacology*
  • Diuretics / pharmacology*
  • Dogs
  • Dose-Response Relationship, Drug
  • Drug Therapy, Combination
  • Female
  • Furosemide / pharmacology*
  • Male
  • Pyridazines / pharmacology*
  • Renin-Angiotensin System / drug effects*
  • Renin-Angiotensin System / physiology


  • Cardiotonic Agents
  • Diuretics
  • Pyridazines
  • pimobendan
  • Furosemide