A dog hacking while producing phlegm can be worrying, especially if the symptoms persist or worsen over time.
We outline the common reasons why a hacking cough with phlegm happens in dogs, what you can do at home, and when to seek veterinary help.
Dog Hacking Cough and Phlegm: Why It Happens
A dog hacking cough with phlegm typically occurs when the airways are inflamed or infected, causing excessive mucus production.
There are several potential causes for this type of cough, including kennel cough, pneumonia, heart disease, chronic bronchitis, or environmental irritants. Phlegm is produced as a protective response to remove bacteria, viruses, or other irritants from the respiratory tract.
While occasional coughing may be mild, persistent or worsening symptoms can indicate a more serious underlying problem, especially in puppies, older dogs, or those with pre-existing health conditions.
Dog Hacking Cough and Phlegm: Common Causes
Kennel Cough
Kennel cough is one of the most common causes of a hacking cough with phlegm in dogs.
This highly contagious infection affects the trachea and bronchi, leading to inflammation and increased mucus production.
Dogs with kennel cough often have a dry, honking cough initially, which can progress to wet coughs with phlegm.
You might notice sneezing, mild fever, lethargy, and a reduced appetite. While healthy adult dogs often recover with supportive care, puppies and immunocompromised dogs may develop severe respiratory complications requiring veterinary intervention.
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Pneumonia
Pneumonia, an infection of the lungs, can cause a hacking cough accompanied by thick phlegm.
Bacterial, viral, or fungal pathogens can lead to inflammation and fluid accumulation in the lungs, making it difficult for the dog to breathe comfortably.
Dogs may also exhibit rapid or labored breathing, nasal discharge, lethargy, and loss of appetite.
Pneumonia is serious and often requires prompt veterinary care, including antibiotics or other treatments to prevent further lung damage and systemic illness.
Chronic Bronchitis
Chronic bronchitis is a long-term inflammation of the airways that produces persistent coughing and mucus production.
Dogs with chronic bronchitis may develop a wet, hacking cough that worsens with exercise or excitement.
Phlegm may be clear, yellow, or greenish, depending on the presence of infection or irritation.
You may also notice wheezing or difficulty breathing over time. Management often involves medications to reduce inflammation and improve airway function, as well as lifestyle adjustments to minimize exposure to irritants.
Heart Disease
Heart disease, particularly congestive heart failure, can lead to coughing and phlegm as fluid backs up in the lungs and airways.
Fluid accumulation causes irritation, triggering persistent coughing and sometimes frothy or foamy phlegm.
Other signs may include difficulty breathing, fatigue, swollen abdomen or limbs, and pale or bluish gums.
Early diagnosis and treatment are crucial to manage fluid buildup, reduce coughing, and prevent more severe complications like pulmonary edema or heart failure progression.
Respiratory Infections
Viral or bacterial infections affecting the nose, throat, or lungs can cause both coughing and mucus production.
These infections often start with sneezing or a mild cough, progressing to a wet cough as phlegm accumulates.
Dogs may also have fever, nasal discharge, or reduced appetite. Prompt veterinary evaluation is important to determine if antibiotics, antivirals, or supportive care are needed to prevent the infection from worsening or spreading to other dogs.
Allergies
Smoke, dust, pollen, strong cleaning chemicals, or other airborne irritants can trigger coughing with phlegm in sensitive dogs.
Allergens inflame the airways, leading to increased mucus production and a persistent hack.
Some dogs may also sneeze, paw at their face, or have watery eyes. Long-term exposure can worsen respiratory inflammation and increase susceptibility to infections. Identifying and reducing exposure to these irritants is an important step in managing symptoms.
Read more: Dog Constantly Hacking and Gagging (What You Need to Know)
What to Do
Observe your dog closely to determine the frequency, severity, and triggers of coughing. This information helps your veterinarian identify the underlying cause and tailor treatment.
Keep your dog in a calm environment, minimizing activity that may exacerbate coughing, and ensure they have access to clean water to help thin mucus. Using a humidifier can ease airway irritation, especially in dry climates or heated indoor spaces.
Maintain a clean living area, free from dust, smoke, and strong chemical odors, to reduce exposure to environmental triggers. Offer gentle care and monitor for changes in appetite, energy levels, or breathing patterns, as these can indicate worsening illness.
When to Call or Visit Your Vet
Seek immediate veterinary attention if your dog has labored or rapid breathing, blue or pale gums, vomiting, collapse, or coughing up blood.
Consult a veterinarian if the cough and phlegm persist for more than a few days, worsen over time, or are accompanied by lethargy, fever, or loss of appetite.
Puppies, senior dogs, and dogs with existing health conditions should be assessed promptly, as respiratory infections and heart issues can progress quickly and lead to severe complications. Early intervention is key to preventing long-term damage and improving recovery outcomes.
Read more: Dog Constantly Hacking (Why it happens)
Key Takeaway
A hacking cough with phlegm in dogs can result from several causes, including kennel cough, pneumonia, chronic bronchitis, heart disease, respiratory infections, and exposure to environmental irritants.
While mild cases may be managed at home with observation and environmental adjustments, persistent, worsening, or severe symptoms require veterinary attention.
Monitoring your dog, keeping their environment clean, providing supportive care, and seeking timely medical evaluation are essential steps to help your dog breathe easier and recover comfortably.