TL;DR: A faint whistling sound during purring is usually caused by slightly narrowed nasal passages and is typically not an emergency if your cat is breathing comfortably and acting normally.
Why is my cat making a whistling sound while purring?
- Air passing through a slightly narrowed section of the nasal passages or upper airway.
- Small amounts of dried mucus, similar to a human with a mild stuffy nose.
- The natural anatomy of your cat's nose creating a high-pitched "whistle" during deep breathing.
Is it an emergency if my cat whistles while breathing?
The urgency level for a faint whistle is Low. It is rarely a medical emergency if your cat is:
- Acting normally, eating well, and playing.
- Breathing with their mouth closed.
- Showing signs of a benign quirk or mild seasonal allergies.
How do videos and photos help a veterinarian triage my cat?
- Photos allow a veterinarian to check for physical abnormalities like nasal discharge or swelling.
- Videos with clear audio help the vet determine the rhythm and origin of the noise.
- Digital media helps differentiate between a simple nasal whistle and a deeper respiratory issue before an in-person exam.
Clinical Context (Merck Veterinary Manual)
While not explicitly termed "whistling," abnormal respiratory sounds in cats, particularly in conjunction with purring, warrant investigation. Increased respiratory sounds may suggest pulmonary edema, while decreased sounds may indicate pleural effusion. Physical examination frequently demonstrates abnormal heart sounds, including a soft to prominent systolic cardiac murmur and/or a gallop sound. The murmur is often dynamic, increasing in intensity with excitement and decreasing as the cat relaxes. Importantly, a murmur is not present in at least one-third of cats with hypertrophic cardiomyopathy (HCM). If the heart is not enlarged, the sound is more likely a systolic click.
Chapter: Cardiology
Source: The Merck Veterinary Manual, 11th Edition (Page 89)