A combination of hyoscyamine and theophylline for treatment of sick sinus syndrome in a dog

Authors

• Uraiwan Saengkieo, Thonglor International Pet Hospital Rama9; Charoensuk Animal HospitalFollow
• Arisara Kiatsilapanan, Faculty of Veterinary Science, Chulalongkorn UniversityFollow
• Suwanakiet Sawangkoon, Faculty of Veterinary Science, Chulalongkorn University

Abstract

A-12-year-old female West Highland White Terrier presented with a history of cardiac syncope. Physical examination revealed bradycardia. Sick sinus syndrome (SSS) was diagnosed with electrocardiography and 24-hour Holter monitoring. However, the owner made the decision to receive the pharmacological therapy. Therefore, a combination of hyoscyamine sulfate and theophylline was prescribed. Following two adjustments of drug dosage and frequency within a year, the total number of heartbeats increased from 58,091 to 73,686 beats, and the mean heart rate increased from 44 to 59 bpm. After the treatment, the dog became stable and no syncopal episodes were detected, despite the presence of supraventricular and ventricular tachycardias. In conclusion, a combination of hyoscyamine sulfate and theophylline can be considered an alternative treatment in dogs with SSS.

DOI

10.56808/2985-1130.3835

First Page

1

Last Page

8

Recommended Citation

Saengkieo, Uraiwan; Kiatsilapanan, Arisara; and Sawangkoon, Suwanakiet (2026) "A combination of hyoscyamine and theophylline for treatment of sick sinus syndrome in a dog," The Thai Journal of Veterinary Medicine: Vol. 56: Iss. 4, Article 8.
DOI: https://doi.org/10.56808/2985-1130.3835
Available at: https://digital.car.chula.ac.th/tjvm/vol56/iss4/8