Does rapid breathing in dogs or cats always mean pulmonary thromboembolism?

Not necessarily. Rapid breathing can be caused by many conditions, including infection, heart disease, or airway disorders. Your vet will determine the cause through clinical examination and imaging — prompt veterinary assessment is strongly recommended.

What tests will the vet typically arrange during the visit?

Common tests include a complete blood count and biochemistry panel, urinalysis, chest X-ray, and advanced imaging such as a CT scan when needed, to identify the possible cause of respiratory abnormalities.

How often is follow-up needed after treatment?

Follow-up frequency varies by case. In the early phase, check-ups are often needed every few days to two weeks to assess stability; thereafter, blood work and imaging are monitored at intervals of weeks to months, as advised by your vet.

How can I help monitor my pet's condition at home?

Track breathing rate, appetite, activity level, and coughing frequency, and record any abnormal episodes on video to share with your vet. If there is acute deterioration, seek veterinary care immediately.

How much do the tests and treatment usually cost?

Costs vary by clinic and region — ask your vet for an estimate before proceeding.

Disease Guide

Pulmonary Thromboembolism in Dogs & Cats: Symptoms, Diagnosis & Care [2025]

A blood clot in the lungs is a serious emergency that disrupts breathing

Take 1 minute to check the symptoms first

Last updated: 2026/01/06

Pethealthmap Editorial Team

Sources: ACVIM, AVMA, National Taiwan University Veterinary Teaching Hospital

When to See a Vet

Seek Emergency Care Immediately

•Continuous open-mouth labored breathing with no sign of relief
•Gums or tongue turning purple or pale white
•Sudden collapse or prolonged unresponsiveness

Schedule a Clinic Visit Soon (within 24–72 hours)

•Noticeably reduced activity tolerance and easy fatigue
•Persistent cough or significantly increased coughing frequency
•Markedly decreased appetite or abnormal change in water intake

01What symptoms indicate something is wrong?

Pulmonary thromboembolism often causes changes in breathing, heart rate, and mental alertness — symptoms may appear suddenly or worsen gradually.

Weakness, noticeably reduced activity, or tiring easily
Decreased appetite or a significant drop in food intake
Persistent coughing or an increase in coughing frequency
Rapid breathing, panting, or visibly laboured breathing
Rapid heart rate, restlessness, or difficulty settling

Seek emergency care immediately if you notice the following symptoms:

⚠️ Rapid breathing with open-mouth breathing or marked respiratory effort
⚠️ Gums or tongue appearing purple or pale
⚠️ Collapse, prolonged unresponsiveness, or inability to be roused

02How to assess the situation at home? Key observations and when to seek emergency care

Recording specific details of key changes at home can help your vet quickly assess the severity and determine the right time to seek care.

Note when symptoms first appeared and how they have changed over time
Write down any changes in appetite or water intake, with timestamps
Use your phone to record a short video of any coughing or abnormal breathing for reference
Observe and record the frequency and any abnormalities in urination and defecation
Note any changes in alertness, sleep patterns, and activity levels

03How will the vet make a diagnosis? Common diagnostic tests

Your vet will typically start with blood work and chest imaging, with advanced imaging or specialist referral as needed.

Complete blood count and biochemistry panel to assess overall condition

Urinalysis as a baseline reference for body status

Chest X-ray to evaluate lung and heart appearance

Serology or thrombosis-related tests to rule out other causes

CT scan or advanced imaging to confirm the diagnosis and provide detailed assessment

04What treatment and care are needed after diagnosis? Medication, dietary adjustments & home care guide

Treatment focuses on stabilising breathing and addressing the underlying cause; ongoing monitoring and regular check-ups are essential after discharge.

Short-term oxygen support may be needed to stabilise breathing
Treatment tailored to the underlying cause, with scheduled follow-up appointments
Adequate rest and appropriate nutrition to support recovery
Blood work and imaging tracked at follow-up visits to evaluate treatment response
Monitor breathing rate, activity level, and appetite changes at home

05What to prepare before your vet visit? Key information to help your vet identify the cause quickly

Organise a symptom diary with the onset time and subsequent changes

List all current medications and supplements by name

Bring a video of any coughing or abnormal breathing for the vet to review

Record changes in appetite, water intake, and elimination frequency

Bring any previous chest X-rays or diagnostic reports if available

Use a secure carrier and call ahead to book a specialist appointment

This content is for reference only and cannot replace a professional veterinary diagnosis. If your pet shows signs of illness, please seek veterinary care promptly.