why does my cat drool when i pet him

Your cat drools when you pet him most commonly because he is happy, relaxed, and content. When a cat reaches a state of pure contentment, such as when being petted, their jaw and lips relax, which can cause saliva to escape the mouth. This drooling during petting is a normal reaction linked to feelings of pleasure and relaxation, possibly related to memories from kittenhood and a deep trust in you. It is often accompanied by other contentment behaviors like purring and kneading. The drooling can also be explained by stimulation of the parasympathetic nervous system—the system responsible for the "rest and digest" state—where increased saliva production occurs as the cat feels safe and relaxed. However, drooling can sometimes indicate other things, such as anxiety or fear, dental disease, nausea, or exposure to toxins. If the drooling is excessive, constant, or accompanied by other signs like bad breath, difficulty eating, lethargy, or behavioral changes, a veterinary visit is recommended to rule out health problems. In summary, if your cat drools only when you pet him and otherwise seems healthy and happy, it is generally a sign of deep relaxation and affection.