Content continues after advertisement

Nasal Capillariosis Treatment in Dogs

Clinician's Brief (Capsule)


February 2015

Sign in to Print/View PDF

Capillaria boehmi, a capillarid nematode, infects the nasal and sinus cavities of wild and domestic canids. Although rare in pet dogs, nasal capillariosis is a potentially emerging infection in temperate areas of the Americas and Europe. Clinical signs include sneezing, nasal discharge, and epistaxis. This pilot trial investigated the safety and efficacy of a spot-on formulation of 10% imidacloprid with 2.5% moxidectin in treating naturally occurring nasal capillariosis in dogs. Sixteen dogs with C boehmi eggs present on fecal examination were included for study. Diagnosis of nasal capillariosis was confirmed either via rhinoscopy or species-specific PCR on fecal specimens. Dogs were randomly divided into 2 treatment groups; group T (n = 8) were treated, group C (n = 8) received no treatment. Dogs were retested for the presence of C boehmi on day 28 via fecal flotation and either rhinoscopy or species-specific PCR. In group T, 7 of 8 dogs tested negative on day 28; all group C dogs had persistent infection. One group-T dog was persistently infected on day 28 ±2 and was retreated, subsequently testing negative on day 56. Seven animals in group C were given a rescue dose of the spot-on formulation on day 28, and all subsequently tested negative for C boehmi on fecal flotation and species-specific PCR. Clinical signs had resolved for all dogs by the end of treatment. The authors conclude that 10% imidacloprid/2.5% moxidectin spot-on is a promising treatment for naturally occurring nasal capillariosis in dogs. Study was funded by a grant provided by Bayer Animal Health.

10% imidacloprid/2.5% moxidectin spot-on is a promising treatment for naturally occurring nasal capillariosis in dogs.


Nasal capillariosis is a recognized, but incompletely understood condition affecting wild and domestic canids. The causative agent, Capillaria boehmi (syn. Eucoleus boehmi), is potentially spreading in the Americas and Europe, resulting in symptomatic infections. While subclinical infection is possible, dogs with clinical signs exhibit sneezing, reverse sneezing, nasal discharge, and decreased scenting ability. Aberrant migration is possible resulting in meningoencephalitis. Currently, there is no approved treatment for C boehmi infections. In this study, the majority of dogs cleared the infection in a single dose (14/15); the exception was 1 heavily infected dog that cleared the infection after 2 doses. Further study is needed to more accurately define the safety, efficacy, and possible preventive effects with long-term administration as infected dogs are at risk for reinfection.—Chris Adolph, DVM, MS (Parasitology)


For global readers, a calculator to convert laboratory values, dosages, and other measurements to SI units can be found here.

All Clinician's Brief content is reviewed for accuracy at the time of publication. Previously published content may not reflect recent developments in research and practice.

Material from Clinician's Brief may not be reproduced, distributed, or used in whole or in part without prior permission of Educational Concepts, LLC. For questions or inquiries please contact us.


Clinician's Brief:
The Podcast
Listen as host Alyssa Watson, DVM, talks with the authors of your favorite Clinician’s Brief articles. Dig deeper and explore the conversations behind the content here.
Clinician's Brief provides relevant diagnostic and treatment information for small animal practitioners. It has been ranked the #1 most essential publication by small animal veterinarians for 9 years.*

*2007-2017 PERQ and Essential Media Studies

© 2022 Educational Concepts, L.L.C. dba Brief Media ™ All Rights Reserved. Terms & Conditions | DMCA Copyright | Privacy Policy | Acceptable Use Policy