Why Is My Cat Itchy? Scratching, Overgrooming and Patchy Fur Explained
Cats are private about being uncomfortable. Most of the scratching, chewing and licking happens while you are asleep or out of the room, which is why the first thing many owners notice is not the itching at all. It is the fur.
A thin patch on the belly. A bald strip along the back legs. A coat that has gone from sleek to scruffy without anything obvious changing. If your cat is itchy or losing fur in patches, here is what is usually behind it, what the location of the patches tells you, and why this is one to take to your vet rather than try to solve with a change of food.
First, the important bit
An itchy cat with patchy fur needs a vet appointment. Not because it is necessarily serious, but because the common causes look almost identical from the outside and several of them need a specific treatment that nothing else will fix.
One of them, ringworm, is a fungal infection rather than a worm at all, and it passes to people and to other pets in the house. That alone makes it worth ruling out early rather than waiting to see how things go.
Take a photo of the affected areas before you go. Cats have a way of looking perfectly fine the moment they arrive at the surgery.
The most common causes of an itchy cat
Fleas, including on cats who have never had fleas
Fleas are the single most common cause, and the most commonly dismissed. Many cats are actually allergic to flea saliva, which means a reaction wildly out of proportion to the number of fleas involved. A cat can be intensely itchy from a handful of bites, and a fastidious groomer will have removed the evidence long before you go looking for it.
If your cat is scratching but you cannot find fleas, that does not rule them out. It is one of the reasons vets often treat for fleas first regardless.
Mites
Ear mites cause head shaking, scratching around the ears and a dark, crumbly discharge. Other mites affect the skin and cause scabbing and hair loss. Both are common, both are treatable, and both need diagnosing properly.
Ringworm
A fungal infection producing round patches of hair loss, often with flaky or crusty skin, most commonly on the head, ears and paws. It is contagious to humans and other animals, so it needs confirming and treating rather than watching.
Food sensitivity
Genuine food allergy in cats is less common than the internet suggests, but it does happen, and it tends to show up as itching around the head, neck and ears alongside digestive upset. When a cat does react to something in their diet it is usually a protein they have been eating regularly rather than grains or additives.
Diagnosing it properly means a strict elimination diet run under veterinary supervision, usually over eight to twelve weeks with nothing else passing their lips. Swapping brands at home and watching for a month will not give you a reliable answer, and it can muddy the picture for your vet.
Environmental allergies
Pollen, house dust mites, mould spores and grasses affect cats much as they affect people, except that in cats it presents through the skin rather than the nose. These allergies are often seasonal, so if your cat is itchy every spring and settles every autumn, that is a strong clue worth mentioning.
Overgrooming, and what is underneath it
Cats groom to soothe themselves. A cat who is anxious, bored or unsettled may groom one area so persistently that the fur simply wears away, leaving skin that is bare but not damaged or scabbed.
Common triggers include a new cat in the house or in the garden, a house move, building work, a new baby, a change in routine or competition over litter trays and feeding spots.
One important caveat: cats also overgroom over a spot that hurts. Bladder discomfort, joint pain and old injuries can all show up as a bald patch. Behavioural overgrooming is a diagnosis your vet reaches after ruling out pain, not a conclusion to jump to at home.
Something systemic
Less often, coat changes point to something internal. An overactive thyroid, diabetes and other conditions can all show up first as a coat that has lost condition or a cat who has stopped grooming properly. This is more likely in older cats, and it is another good reason for a proper check.
Where the patches are tells you something
Location is one of the most useful things you can bring to the appointment: