A case of long-term sildenafil therapy in a young dog with pulmonary hypertension

J Vet Med Sci. 2007 Oct;69(10):1073-5. doi: 10.1292/jvms.69.1073.


A 7-month-old male Papillon was presented to us with mild dyspnea, cyanosis and a diastolic murmur detected by cardiac auscultation. Echocardiography revealed severe pulmonary arterial hypertension (PH), and administration of 1 mg/kg of oral sildenafil, a phosphodiesterase type 5 (PDE5) inhibitor, twice daily was initiated. Exercise capacity, cyanosis, dyspnea and cardiac murmur were improved after therapy for 4 weeks. PCV was remarkably high (74%) after therapy for 3 years, however, increasing the dose of sildenafil decreased this value (60%). Follow-up after therapy for 4 years revealed that treatment with oral sildenafil only continued to provide the dog with an excellent quality of life, without any side effects.

Publication types

  • Case Reports

MeSH terms

  • Animals
  • Dog Diseases / drug therapy*
  • Dogs
  • Hypertension, Pulmonary / drug therapy
  • Hypertension, Pulmonary / veterinary*
  • Male
  • Piperazines / therapeutic use*
  • Purines / therapeutic use
  • Sildenafil Citrate
  • Sulfones / therapeutic use*
  • Vasodilator Agents / therapeutic use*


  • Piperazines
  • Purines
  • Sulfones
  • Vasodilator Agents
  • Sildenafil Citrate