Solar dermatitis is skin damage caused by the sun. Fur shields the skin from ultraviolet (UV) light, so the damage turns up mostly on skin that has little hair and little pigment [1][2]. In cats that usually means the ear tips, and white cats or cats with white ears are the ones most at risk [1][2].
It matters because the damage can turn into cancer. Long-term UV exposure is a proven cause of squamous cell carcinoma, a skin cancer, and of the sun-damaged patches that come before it [1][2].
If your cat has red, scaly, crusted or sore ear tips that do not heal, see your vet. Do not put any cream or sunscreen on your cat unless your vet tells you to.
Which cats get it
- White or light-colored cats: pale skin has less melanin, the pigment that soaks up and scatters UV rays, so it is less protected [1][2].
- Cats that spend time in the sun: the risk rises with the amount of sun a cat gets, and many cats choose to lie in sunny spots [2].
- Other light, thin-haired skin: besides the ear flaps, the nose, eyelids and temples are the areas most often linked to sun damage in cats [1].
Signs of solar dermatitis
- Early: red, inflamed skin on the ear tips [2].
- Thicker skin: the sun-damaged stage that comes before cancer, called actinic or solar keratosis, shows as thick, scaly patches [2].
- Later: scabs and sores that do not heal [3].
A sore that does not heal is the sign to watch for. A review of this cancer in cats says vets should consider it whenever a light-colored cat has a scabby sore on the eyelids, ears or nasal planum that will not heal [3]. The nasal planum is the hairless skin of the nose.
Why it can lead to skin cancer
Actinic keratosis is a precancerous stage: with ongoing sun exposure, it can turn into squamous cell carcinoma [1][2]. Actinic keratosis is sun-damaged skin.
These sun-linked cancers are slow to spread to other parts of the body, but they can cause a lot of damage where they grow. They often come back, and new ones can appear in other sun-damaged skin [2].
For other skin lumps in cats, see lumps and bumps on cats.
Sun damage is different from photosensitization, where the skin overreacts to light. See photosensitization in dogs and cats.
How vets find out what it is
Skin cancer can look like other sores, so a vet needs to examine any ear-tip sore that does not heal [3]. Your vet may take a biopsy, a small piece of skin checked under a microscope, to see what kind of change it is [1].
How vets treat it
Early sun damage. The usual first step is to keep an at-risk pet out of the sun when UV levels are highest [2]. Your vet will tell you what else your cat needs.
Skin cancer of the ear tips. A review says small, early cancers on the ear tips are fairly easy to treat, while more advanced ones are harder to manage and can change how the cat looks [3]. Because new spots can keep appearing, some animals need more than one operation over their lifetime [2]. Your vet chooses the treatment that suits your cat.
At home, as directed by a vet:
- keep your cat out of strong sun in the way your vet advises;
- use only the creams or sunscreen your vet recommends, and only as shown;
- stop your cat from scratching the ear tips in the way your vet advises;
- watch the ear tips, nose and eyelids for new red, scaly or crusted spots;
- go back for every recheck.
Preventing sun damage
Preventing further sun damage is the most important step for cats at risk. Vets commonly advise keeping high-risk pets out of the sun during the peak UV hours, which in practice often means keeping them indoors [2].
Windows let UV through. A review notes that UV light passes through window glass, so a cat lying in a sunny window can still be exposed unless the window has a UV filter or an opaque cover [2]. A study of cats with ear tumors also raised indoor exposure through glass as a possibility [1].
Shade alone may not be enough. A cat that likes to sunbathe will often leave the shade, and light bouncing off bright surfaces still reaches the skin [2].
Sunscreen is vet-led only. There is very little research on whether sunscreen is safe or useful for pets [2]. Cats and dogs are more likely than people to swallow a product put on their skin, and their skin is thinner, so it may absorb more [2]. Do not use a sunscreen made for people on your cat. Ask your vet before you use any sunscreen.
Outlook
Outcomes vary between cats:
- A review says early cancers on the ear tips are fairly easy to treat, but more advanced ones are harder to manage and can affect how the cat looks [3].
- New sun-related spots can appear later in skin that has already been damaged [2].
These are statements about groups of cats. They cannot predict how one cat will do. Your vet can explain what this means for your cat.
When to see your vet
See your vet if your cat has:
- red or scaly ear tips [2];
- crusts, scabs or sores on the ear tips [3];
- a sore on the ears, nose or eyelids that does not heal [3];
- thick, scaly patches on the ear tips [2].
See your vet again if a treated area changes, grows, bleeds or does not heal.
FAQ
Can cats get sunburned ears?
Yes. Sun damage shows up most on thinly haired, pale skin, and the ear tips of white cats are a classic spot [1][2].
Is solar dermatitis cancer?
Not at first, but it can become cancer. Sun-damaged skin can go on to develop squamous cell carcinoma [1][2].
Can I put sunscreen on my cat?
Only if your vet recommends one. Little is known about sunscreen safety in pets, and cats tend to lick off what is put on their skin [2].
Will my cat lose part of its ear?
It varies, and no one can promise it. Advanced cancers can change how a cat looks [3]. See the Outlook section above.
The bottom line
Solar dermatitis is sun damage to thin, light-colored skin, most often the ear tips of white cats. It starts as redness and scaling and can lead to scabs, sores and a skin cancer called squamous cell carcinoma. Keep at-risk cats out of strong sun, remember that UV passes through window glass, use sunscreen only on your vet’s advice, and see your vet about any ear-tip sore that does not heal.
This article is for general information only and does not replace advice from your veterinarian. If your cat has a sore on the ear tips that does not heal, see your vet.
Sources
- Millanta F, Parisi F, Poli A, Sorelli V, Abramo F. Auricular Non-Epithelial Tumors with Solar Elastosis in Cats: A Possible UV-Induced Pathogenesis. Vet Sci. 2022;9(2):34. CC BY 4.0. https://pmc.ncbi.nlm.nih.gov/articles/PMC8874616/
- Granados-Soler JL, Story MM, Allavena R, Prada J. Ultraviolet Light-Induced Skin Cancer and the Safety of Sunscreen Use in Pets: An Important but Under Researched Aspect of Companion Animal Health. Vet Sci. 2026;13(7):605. CC BY 4.0. https://pmc.ncbi.nlm.nih.gov/articles/PMC13416697/
- Murphy S. Cutaneous squamous cell carcinoma in the cat: current understanding and treatment approaches. J Feline Med Surg. 2013;15(5):401-7. https://pubmed.ncbi.nlm.nih.gov/23603503/