Updated November 28, 2020
Hair loss is a good example of how the skin problems of cats are different from dogs. It’s got a lot to do with their special grooming behaviour.
The Overgrooming Myth
When cats have itchy skin they don’t scratch the same way dogs do. More commonly, they just lick the area more. This damages the hair shafts, which break, and bald spots appear.
From the outside, the skin often looks normal. Once upon a time, at this point, vets would say, “your cat is overgrooming”. Boom. In one word, it’s suddenly the cat’s fault.
But it gets worse. I once heard an eminent vet say that prednisolone has calming effects on cats and that’s why it works on ‘overgrooming’. Well, prednisolone is actually an anti-inflammatory steroid. Despite the fact that ‘pred’ could only be working by suppressing an itch, some vets were willing to invent new properties for the drug rather than accept the reality.
So what is the reality?
Why Cats Lose Hair
Hair loss has at least three causes:
- Diseases causing itch such as allergy or fleas
- Diseases causing the hair to break or fall out
- Diseases causing overgrooming
As you can see, I don’t deny the existence of psychological overgrooming. It just needs it to be considered last. The reason is simple: the first two will get better with specific treatment. Overgrooming is a diagnosis of exclusion and often ends up being hard to treat.
The mystery photo shows hair loss between the back legs of our elderly patient Purdy. It would have been so easy to call it psychological or hormonal.
If we call a cat an overgroomer, we’re in danger of giving up on them before we start. We need to consider all three causes. Lets start with the itch.
What Causes Itchy Skin In Cats
Itchy skin in cats is usually caused by either:
- Flea bite
- Environmental allergy
- Food allergy
- Mites (rarely)
Now have a look at the picture at the start. It shows the most common patterns seen for these three causes in 502 cats (reference below). The colours indicate the percentage of cats in each group that were affected in that area.
- light blue is 0-20%
- blue is 20-40%
- yellow is 40-60%
- orange is 60-80%.
Several observations spring out straight away:
- Hair loss on the lower back and tail is most often flea-related
- Hair loss on the belly happens with everything
- Hair loss on the front and back legs: probably not food
- Facial problems happen with everything but head & neck problems are more common for food
- Nothing is true 100% of the time
Point 5 means that although patterns are useful to tell us what to try first, we can’t use them for a diagnosis.
So although Purdy does have hair loss on the belly, here’s why she didn’t have these diseases:
- She gets treated every month with Revolution for fleas
- Environmental allergies such as to dust mites, pollens and grasses almost never start in old age
- Food allergies are usually a lot more severe and widespread
- The lesions aren’t typical for mites
So what about the second cause of hair loss?
What Causes The Hair To Fall Out?
Not many diseases cause spontaneous alopecia. A fungal infection called ringworm (pictured under ultraviolet light) is most common. However, Purdy just doesn’t fit the age or pattern for ringworm, and the skin changes aren’t consistent either.
Hair can also fall out with mites (very rare, wrong spot) and breed-related ‘disorders’. Pictured is my disorder of a Devon Rex, Grendel. All the rex breeds have hair that grows poorly and so most of them will have bald patches at times. That’s just the way they are.
So, by exclusion, it seems like Purdy will be overgrooming after all.
What Causes Overgrooming?
Causes of true overgrooming include anything that might affect your cat’s emotional well-being. That can be:
- a house move
- new baby
- another cat or dog
- health problems
You can read more examples at our page on Stress and anxiety in cats.
In this case, Purdy’s problem was caused by hyperthyroidism. She was brought to me for the hair loss, but I noticed she wasn’t right in other ways and ordered a blood test.
Thyroid disease makes cats edgy and highly strung. Once we controlled her thyroid problem, she relaxed and the hair grew back.
Do Hormones Cause Hair Loss in Cats?
Hormonal causes come up online as the top cause for feline alopecia. Well, Google if you’re listening, the right answer is: almost never. Purdy’s example is an unusual way to recognise thyroid problems. I also see hair thinning with untreated diabetes, but that’s the least of these cats’ problems. And as for the major cause in older dogs, Cushing’s disease in cats is too rare to mention.
Hair Loss Treatment in Cats
So to finish, let’s get practical and imagine you’ve got a cat with bald spots. You now know it can be caused by a lot of things. What do you do?
First, get a checkup with your vet. I’ve only discussed the common, typical causes of hair loss but your vet knows a lot more.
Then, if your vet doesn’t find something, they will probably advise a similar pathway to the one I used above:
- Rule out parasites with an appropriate treatment
- Rule out food allergy via a diet trial
- Investigate environmental allergy (may require a treatment trial)
- Perform blood and urine testing if not done before
- Consider psychological causes
After this, if you’re not getting improvement, talk to your vet. There are always other ideas such as ringworm culture or biopsy, or you may be recommended referral to a specialist.
Have something to add? Comments (if open) will appear within 24 hours.
By Andrew Spanner BVSc(Hons) MVetStud, a vet in Adelaide, Australia. Meet his team here. The information provided here is not intended to be used as a substitute for going to the vet. If your pet is unwell, please seek veterinary attention.
Hobi, S., Linek, M., Marignac, G., Olivry, T., Beco, L., Nett, C., … & Koebrich, S. (2011). Clinical characteristics and causes of pruritus in cats: a multicentre study on feline hypersensitivity‐associated dermatoses. Veterinary dermatology, 22(5), 406-413.
Hi thanks for replying, it’s not the first time, his grooming of stomach has been ongoing 6 months +, the vet examined thyroid and said it was OK, although no blood test taken. I forgot to mention he is on Meloxicam for past 3yrs for arthritis.
My 20 year old male cat is licking his stomach and side of hind legs raw. Vet said it could be stress or allergy. I’ve tried feliway diffuser, flea treatment, changed his litter and food type. Used hibiscrub from vet on legs which has helped, but his stomach is still pink and no fur.
Hi Lisa. They may be right, but I would also think about an underlying health condition if this is the first time it has happened. For example, in this article there is a cat who had thyroid disease and did the same thing. Alternatively, you may need a systemic treatment like prednisolone.
Hi thanks for replying, it’s not the first time, his grooming of stomach has been ongoing 6 months +, the vet examined thyroid and said it was OK, although no blood test taken. I forgot to mention he is on Meloxicam for past 3yrs for arthritis.
Hi Andrew,
My one cat has about a 1 inch bald patch on his tail and has been there for about one month which occurred following a fight with one of our other cats. I thought the fur would fill back in however it hasn’t, and has since been replaced with dry scaly skin. I have been trying to schedule an appointment with our vet however they’ve been very busy currently. Are there any treatments out there that I can use to try to help promote increased hair growth in his tail? This is the only bald patch that he has. It’s also very obvious as he is an all black cat.
Hi Allie. Sorry, without a diagnosis the best you could do would be to apply a good flea control.
Hey Andrew,
I’m at a loss and could use your help. My 8 y.o. male cat (not sure of his breed) is getting bald patches on his middle and lower belly, on his “ankles?” and on the Carpal pads.
I took him to the vet about a month ago and they gave him a steroid shot and said he is overall healthy and that it could be anxiety or psychological.
We haven’t changed his food, litter, or environment. His demeanor is normal and hasn’t changed in the slightest. He isn’t lethargic and still plays! It’s just very bazaar and we aren’t sure what’s wrong with him. We first noticed the balding about 4 months ago and have tried OTC anti-fungal spray as well as a vest to help prevent the licking. His urination and bowel movements are regular and don’t seem out of the ordinary and still eats and drinks. We have no other cats, animals or children.
Any advice would be so helpful!
Hi Jenna. As you can tell from the article, I only consider hair loss in cats to be psychological when the other more common causes have been ruled out. Firstly, always use a veterinary grade flea control, not one from the supermarket. Then, sometimes what your vet has done with a steroid trial (I use tablets or drops) is not a bad idea, and then a food trial.
Hi Andrew,
My 1 yr old Rex Cornish female completely lost hair on the back of her neck and the top of her head.
I had changed her food for a chicken and rice one because she was gaining weight… But the breeder told me that she may be allergic to chicken food. I have returned to the salmon food. As I read your article, Rexes race do have problems with hair loss. So should I worry about the fact my Rex become to have bald spot? Can I do something to make it regrowth? Or like Grendel, it can genetic and permanent hair loss?
Thank you
Hi Nathalie. Rex breeds have highly variable hair coverage from individual to individual, and it also changes with the seasons (I assume that you are entering summer which is typically the worst time). If the skin looks normal and there is no excessive scratching or licking, I would not be too concerned about allergy. As much as I cannot be sure without taking a look, it sounds normal to me.
Hi Andrew,
I think our cat has a patch of ringworm, it was a tiny spot that seemed like it was normal for him, a bit of uneven hair growth or something, but it suddenly got bigger. It’s on his shoulder blade area. The patch appears sore, though the other owner doesn’t seem to think its an issue requiring a vet visit. If we were to treat him for ringworm without a formal diagnosis is this dangerous? He is currently taking 2.5mg Felimazole twice daily for a thyroid condition. Thanks for your consideration and advice.
Hi Alison. It’s very unlikely to be ringworm at his age unless you’ve recently been handling kittens. Given that he is on anti-thyroid medication, it’s possible that this is a side effect, although we usually see the skin sores on the head. Regardless of cause, it’s more likely to be a bacterial infection than fungal (which are also rarely sore). By the way, I have a problem with using anti fungal creams on anything but very small areas in cats due to the inevitable ingestion that will occur.
Good Evening, what do you suggest to treat dandruff?
My 3 1/2 year old Burmese is an inside cat and has terrible dandruff. Her diet consists of Royal Canin, Neutered Young Female biscuits, raw chicken wings and beef cubes.
Thanks for any advice you can give.
Hi Alice. Dandruff usually has the same causes as hair loss, with particular emphasis on parasites. Therefore I would start with using Revolution and then see your vet for the other options.
However, severe dandruff in cats (click the link to read more) is special in that it can also be caused by a LACK of grooming. Since you have a breed prone to dental problems, it’s worth considering even at such a young age.