Healthy cats do not drool. However, it
is common for cats to drool when they know they are going to be given an
unpleasant-tasting medicine or receive an injection. This is psychological. A
few cats will also drool when they are purring and very relaxed. It is
important to know what is normal for your individual cat.
Keep in mind that an animal who drools excessively and acts irrationally
could have rabies. Exercise great caution in handling such an animal.
Shedding is a cat’s natural process of losing dead hair. Outdoor cats may lose more hair in the spring and fall and retain more fur in the winter, while indoor cats can shed all year round. Regularly grooming your cat and vacuuming hair from your house should minimize the inconvenience of shedding. However, if you see bald patches in your cat’s fur or notice a significant loss of hair, the underlying cause may be a health-related problem and should be investigated by a veterinarian.
Drooling accompanied by signs of ill health, such as watering of the eyes,
is quite likely due to a feline viral respiratory infection. Young cats with liver shunts
will drool excessively. Mouth infections and foreign bodies in the mouth are
accompanied by drooling. Heat stroke can cause excess salivation, as can
certain poisons (such as insecticides and arsenic).
Treatment: This is contingent on identifying the cause of the drooling.
WebMD Veterinary Reference from "Cat Owner's Home Veterinary Handbook"