Start with the patient, then localize the problem
First, assess breathing effort and overall stability. Marked respiratory distress, cyanosis, collapse, or open-mouth breathing in a cat call for urgent assessment and stabilization. Routine diagnostic steps may need to wait until the patient can tolerate them.
For a stable patient, check:
- Appetite and attitude: Is the patient eating, alert, and behaving normally?
- Respiratory pattern: Is there increased effort, resting tachypnea, or an abnormal breathing pattern?
- Airway findings: Do signs appear to originate from the upper airways, or is there concern for pulmonary involvement?
- Clinical course: Are signs improving, persistent, or getting worse?
- Risk factors: Review recent boarding or shelter exposure, vaccination status, immunosuppression, and possible aspiration.
A coughing patient with normal respiratory effort and appetite may need a different plan from one with tachypnea, lethargy, and abnormal lung findings.
The three respiratory triage pathways
| Clinical picture | What to consider |
|---|---|
| Acute, uncomplicated presentationNormal appetite and attitude, no systemic illness, and no concerning evidence of pneumonia. | Supportive care, infection control, and monitoring are often appropriate. Routine antibiotics are generally unnecessary. |
| Persistent, worsening, or systemically unwell patientFever, lethargy, poor appetite, or a concerning disease course. | Reassess the diagnosis and look for bacterial complications or another underlying cause. Consider antimicrobials when the clinical evidence supports bacterial involvement. |
| Suspected pneumoniaTachypnea, increased respiratory effort, concerning thoracic findings, or systemic illness raising suspicion of lower respiratory disease. | Assess severity and investigate pulmonary involvement. Diagnostic findings and patient stability guide treatment and the need for hospitalization. |
These pathways help organize triage. Individual findings cannot confirm a bacterial infection or exclude pneumonia.
Seven days of coughing. Does this dog need antibiotics?
Consider a dog that is bright, eating normally, and has been coughing for a week. Duration alone gives you little basis for choosing an antimicrobial.
If examination finds normal respiratory effort, no systemic illness, and no concerning evidence of pneumonia, supportive care and monitoring are reasonable for an uncomplicated canine infectious respiratory disease complex (CIRDC) presentation. Reduce exposure to other animals and give clear reassessment instructions.
If the dog develops tachypnea, increased effort, lethargy, or reduced appetite, reassess promptly and investigate possible pulmonary involvement. Those findings change the plan even before day 10.
Working through a respiratory case?
Open Vetool's Respiratory Infection Triage to work through the patient details alongside your clinical assessment.
When should antibiotics enter the plan?
Most uncomplicated canine infectious respiratory disease complex (CIRDC) cases and many feline upper respiratory infections do not require systemic antibiotics. ISCAID supports observation and supportive care in clinically well patients without findings suggesting bacterial complications.
When the patient is otherwise well
A bright dog with an acute cough, normal appetite, and no concerning findings on examination may not benefit from antibiotics. The same principle applies to many cats with uncomplicated upper respiratory signs.
Supportive care, reducing exposure to other animals, and clear reassessment instructions are part of the plan.
When the clinical picture changes
Fever, lethargy, reduced appetite, progressive illness, or findings concerning for lower respiratory disease warrant further assessment. These findings may increase concern for bacterial involvement, but they can also occur with viral infection or other respiratory conditions.
When bacterial infection is clinically suspected, antimicrobial selection should reflect the likely pathogens, species, previous treatment, and local susceptibility patterns.
Persistent signs at 10 days warrant reassessment. Duration alone does not establish a bacterial indication. Investigate further when the course is atypical, and reassess sooner if the patient deteriorates.
Suspected pneumonia changes the workflow
Once pulmonary involvement is suspected, the assessment goes beyond deciding whether to prescribe an oral antibiotic.
Thoracic radiographs and a complete clinical assessment help investigate pneumonia. CBC findings may provide additional information about systemic inflammation.
Where clinically appropriate and safe, collect lower-airway samples for cytology, culture, and susceptibility testing before starting antimicrobials. These results can guide treatment.
An unstable or oxygen-dependent patient may not tolerate airway sampling. Do not delay stabilization or necessary antimicrobial treatment to obtain a sample or wait for culture results.
Severity changes the next step
A stable patient with mild pulmonary disease may have different treatment options from one with respiratory compromise or suspected sepsis. ISCAID's empirical oral doxycycline option is limited to mild pneumonia suspected to involve Bordetella bronchiseptica or Mycoplasma species, without systemic signs such as fever, dehydration, lethargy, or respiratory distress.
For hospitalized pneumonia patients, ISCAID generally recommends parenteral antimicrobial treatment. Severe bacterial pneumonia may require hospitalization and close monitoring. Review treatment as diagnostic results and the patient's condition change.
An aspiration event also needs careful interpretation. Aspiration can cause chemical lung injury, bacterial pneumonia, or both; not every aspiration event requires antibiotics.
For cats, keep the ocular findings in view
Feline upper respiratory infections commonly involve feline herpesvirus-1 (FHV-1) or feline calicivirus (FCV), sometimes alongside bacterial pathogens.
Purulent nasal or ocular discharge increases concern but does not, on its own, confirm bacterial infection. Viral inflammation can produce similar secretions.
Assess oral ulceration, conjunctivitis, corneal changes, and appetite alongside the respiratory signs. Supportive care includes attention to hydration, food intake, and reducing stress.
Severe ocular disease or suspected herpetic keratitis may need additional ophthalmic assessment and specific treatment, independently of the routine systemic antibiotic decision.
Reassess the course, not only the cough
Before completing the plan, document what would change the initial decision.
For patients managed supportively, review whether appetite, activity, breathing, and respiratory signs are improving. Worsening signs or new systemic illness warrant reassessment.
For patients receiving antimicrobials, review the clinical response and whether diagnostic findings support continued therapy. Reconsider the diagnosis if the expected improvement does not occur.
For suspected or confirmed pneumonia, reassessment may include clinical examination, laboratory findings, and repeat imaging when indicated. Culture results can guide treatment adjustment or de-escalation.
Before you finish the assessment
- Respiratory stability and effort assessed
- Upper-airway signs and possible pulmonary involvement considered
- Appetite, attitude, fever, and illness progression reviewed
- Exposure history and relevant risk factors recorded
- Antibiotic decision supported by the clinical findings
- Diagnostic and reassessment plan documented
Apply the triage pathway to your patient
Review the respiratory triage pathway in Vetool as you work through the diagnostic, supportive-care, and antimicrobial decisions for your patient.
Frequently asked questions
Does green or yellow nasal discharge mean antibiotics are needed?
No. Purulent discharge can occur with viral infections as well as bacterial disease. Interpret it alongside the patient's systemic signs and clinical course.
Does coughing for more than 10 days mean bacterial infection?
No. Persistent coughing warrants reassessment, including consideration of alternative causes. Duration alone does not establish a bacterial diagnosis or justify antibiotic treatment.
Does every respiratory infection need a PCR panel?
Usually not in a typical, uncomplicated individual case. Testing may be more useful during outbreaks, severe disease, persistent illness, or when identifying a pathogen would change management. A positive PCR result needs clinical interpretation: healthy carriers and recent vaccination can affect results.
References
- Lappin MR, Blondeau J, Boothe D, et al. Antimicrobial use Guidelines for Treatment of Respiratory Tract Disease in Dogs and Cats. Journal of Veterinary Internal Medicine. 2017;31:279-294. Read the ISCAID guideline.
- Frey E, Costin M, Granick J, et al. 2022 AAFP/AAHA Antimicrobial Stewardship Guidelines. Journal of the American Animal Hospital Association. 2022. Read the AAHA guidelines.
- Carey SA. Clinical Evaluation of the Respiratory Tract. Chapter 212. Veterinary internal medicine reference chapter supplied for clinical review.
- Contreras E. Feline Upper Respiratory Infections. Chapter 205. Veterinary internal medicine reference chapter supplied for clinical review.
Disclaimer
For veterinary professional education and clinical workflow support only. This guide does not replace patient-specific assessment, clinical judgment, current guidelines, product labeling, local prescribing regulations, or referral when indicated. The attending veterinary professional is responsible for diagnostic and treatment decisions.