SYMPTOM
Drooling
Owners may observe drooling in their pet.
Various conditions
This symptom can occur in multiple conditions and warrants further assessment.
Dental and Oral Disease
Dental and periodontal disease, including gingivitis and tooth resorption, is the leading cause of excess salivation in cats. Resorptive lesions expose sensitive dentine and pulp, and cats respond with pain-driven drooling, often alongside reluctance to eat hard food or head-shaking after a bite. Older cats are disproportionately affected, with tooth resorption reported in a large proportion of cats over ten years.
Viral and Inflammatory Oral Disease
Feline calicivirus and chronic gingivostomatitis produce painful ulceration across the tongue, gums and palate, driving persistent drooling that can appear frothy or blood-tinged. Outbreaks are common in multi-cat households, rescue catteries and kittens with incomplete vaccination. Stomatitis tends to run a chronic, relapsing course once established.
Toxic and Irritant Exposure
Contact with bitter-tasting plants, cleaning agents, or permethrin-based flea treatments intended for dogs can trigger sudden, profuse drooling in cats, who lack the liver enzymes to safely process permethrin. Onset is typically rapid, within minutes to a few hours of exposure, and may be accompanied by tremors or agitation. Cats grooming a treated housemate dog are a recognised route of exposure.
Neurological and Neuromuscular Dysfunction
Facial nerve paralysis and trigeminal neuritis interfere with the ability to close the mouth, retain saliva, or coordinate swallowing, leading to constant drooling and a dropped-jaw appearance. Trigeminal neuritis often has an acute onset and tends to resolve gradually over several weeks. Facial nerve paralysis may follow middle ear disease or occur without an identifiable trigger.
Nausea and Relaxed-State Drooling
Nausea from motion sickness, hairballs or dietary indigestion produces reflex salivation as part of the vomiting pathway, usually settling once the underlying trigger passes. Separately, some cats drool briefly while deeply relaxed, kneading or purring; this is thought to be a benign reflex carried over from nursing behaviour in kittenhood, though the link isn't firmly established. This pattern is intermittent, tied to context, and not associated with pain or oral changes.
Why timing matters
Early observation
Early recognition allows prompt assessment and intervention if needed.
Later presentation
Persistent or worsening signs may indicate progression requiring attention.
The significance of this symptom depends on its context, duration, and associated findings.
Conditions commonly associated
Tooth Resorption
Increased salivation may occur due to oral pain or difficulty swallowing.
Feline Calicivirus
Oral pain from ulcers causes excessive salivation and difficulty swallowing.
Facial Nerve Paralysis
Paralysis of the muscles around the mouth means saliva can no longer be held in properly, leading to drooling from the affected side.
Permethrin Toxicity in Cats
The bitter taste of the product and the nausea it causes commonly lead to marked drooling.
Trigeminal Neuritis
Weakness of the jaw muscles makes it hard to keep the mouth closed, so saliva pools and drips rather than being swallowed normally.
When to explore further
When the symptom is persistent or worsening
When other signs are present alongside
When daily activities or quality of life are affected
When there is uncertainty about the cause
Noting when this symptom occurs, any triggers, and how it changes over time can provide useful information for veterinary discussions.
Last reviewed: 24 April 2026 · Dr Alastair Greenway MRCVS