Not all coughs are created equal. The sound, timing, and character of your dog's cough can provide valuable clues about what is causing it. Learning to describe the cough accurately will help your veterinarian narrow down the diagnosis more quickly.

• Dry, hacking cough: Often associated with kennel cough (infectious tracheobronchitis), a highly contagious respiratory infection. It sounds like your dog is trying to clear something from their throat. This type of cough can also be caused by irritants like dust or smoke.
• Honking cough: A distinctive goose-honk sound is the hallmark of tracheal collapse, a condition most common in small and toy breeds like Yorkies, Pomeranians, and Chihuahuas. The honking often worsens with excitement, pulling on a leash, or hot and humid weather.
• Wet, productive cough: A cough that sounds moist and may produce mucus or fluid suggests pneumonia, bronchitis, or fluid accumulation in the lungs. This type of cough often indicates a more serious condition requiring prompt treatment.
• Coughing at night or when lying down: A cough that worsens when your dog rests or sleeps may indicate congestive heart failure. As the heart weakens, fluid builds up in the lungs, and the cough becomes most noticeable when the dog lies down because gravity redistributes the fluid.
• Gagging or retching after coughing: This can accompany kennel cough or may suggest a foreign body in the throat or esophagus. If your dog seems to be choking or pawing at their mouth, seek immediate care.

Pay attention to when the cough occurs (during exercise, at rest, after eating or drinking), how long each coughing episode lasts, and whether it is getting better or worse over time. This information is extremely valuable to your veterinarian.

The list of conditions that can cause coughing in dogs is extensive. Here are the most frequently encountered causes:

Kennel cough (infectious tracheobronchitis): This is the canine equivalent of the common cold and is caused by a combination of bacteria (Bordetella bronchiseptica) and viruses. It spreads quickly in places where dogs congregate, such as boarding facilities, dog parks, and grooming salons. Most cases resolve on their own within one to three weeks, though some dogs need antibiotics or cough suppressants.

Heart disease: Chronic coughing is one of the earliest signs of congestive heart failure, particularly in older small-breed dogs. As the heart loses its ability to pump effectively, fluid accumulates in the lungs. Treatment focuses on medications to strengthen the heart and remove excess fluid.

Collapsing trachea: The trachea (windpipe) is held open by C-shaped cartilage rings. In some small dogs, these rings weaken over time, causing the trachea to flatten during breathing. This produces the characteristic honking cough and can be managed with medications, weight management, and in severe cases, surgery.

Pneumonia: Bacterial, viral, or fungal infections of the lungs cause pneumonia, which is a serious condition requiring aggressive treatment with antibiotics or antifungals, supportive care, and sometimes hospitalization.

Canine influenza: Dog flu is caused by specific influenza viruses and causes coughing, nasal discharge, fever, and lethargy. Most dogs recover with supportive care, but some develop severe pneumonia.

Heartworm disease: Heartworms are parasites transmitted by mosquitoes that live in the heart and blood vessels of the lungs. As the disease progresses, coughing becomes a prominent symptom. Heartworm disease is preventable with monthly medication and treatable if caught early.

A mild, occasional cough in an otherwise healthy, energetic dog may not require an immediate vet visit. However, you should schedule an appointment if:

• The cough persists for more than a few days
• The cough is getting worse, not better
• Your dog is having difficulty breathing between coughing episodes
• You notice nasal discharge, especially if it is thick, colored, or bloody
• Your dog has a fever, is lethargic, or has lost their appetite
• The cough produces blood or blood-tinged mucus
• Your dog is a senior or has a known heart condition

At the veterinary appointment, expect a thorough physical examination including listening to your dog's heart and lungs with a stethoscope. Depending on the findings, your vet may recommend chest X-rays (to evaluate the heart, lungs, and trachea), blood work (to check for infection or heartworm), or a transtracheal wash or bronchoscopy for more detailed evaluation of the airways.

Treatment varies widely based on the cause. Kennel cough may need only rest and a cough suppressant, while heart disease requires lifelong medication management. Pneumonia may need hospitalization with intravenous antibiotics. Your veterinarian will create a treatment plan specific to your dog's diagnosis and overall health.