A cat that walks in circles is showing a neurologic sign, not a quirk. In most cases the lesion sits in 1 of 3 places: the inner ear, the brainstem, or the forebrain. The circle tells you which. Tight loops of 30 to 60 cm with a head tilt point to the vestibular system; wide loops of 1 to 2 m with a head pressed into a wall point to the forebrain, and that cat needs a vet within 24 hours.
Measure the circle before anything else
Put the cat on a 2 by 2 m floor and watch for 60 seconds without picking it up. Write 4 numbers: direction (clockwise or counterclockwise), diameter in cm, time to complete 1 turn in seconds, and how many times it falls in that minute. A cat doing 5 to 10 turns a minute at 40 cm is a different case from one doing 1 slow turn at 1.5 m. Film 30 seconds from 1 m away with the whole body in frame, because the vet will read the nystagmus and the head tilt from it.
Three localizations, one table
| Localization | Circle diameter (cm) | Head tilt (deg) | Falls per minute | Seen within (h) |
|---|---|---|---|---|
| Peripheral vestibular | 30 to 60 | 15 to 45 | 0 to 2 | 24 to 48 |
| Central vestibular | 60 to 100 | 10 to 40 | 2 to 5 | 24 |
| Forebrain | 100 to 200 | 0 to 10 | 0 to 1 | 8 |
| Toxic | 20 to 150 | 0 to 30 | 3 to 8 | 1 |
| Compulsive | 50 to 80 | 0 | 0 | 168 |
Peripheral vestibular: 60 to 70 percent
Most vestibular cats have a problem in the middle or inner ear: otitis media after an untreated upper respiratory infection, a polyp, or an older cat's ear infection. Signs stay on 1 side. Expect a 15 to 45 degree head tilt, a cat that rolls toward the affected ear, and 1 eye drifting down. Horner's syndrome appears in a share of cases, with a 1 to 2 mm pupil on the same side and a drooping third eyelid. Facial nerve weakness shows as a lip that does not close, so food falls out of 1 side of the mouth. Proprioception stays normal, which is the key split from central disease.
Central vestibular: the flags that change the plan
Central cases come from the brainstem: inflammation, tumor, thiamine deficiency, feline infectious peritonitis, or a vascular event. Four signs move a cat from the 48 hour list to the 24 hour list: vertical nystagmus, nystagmus that changes direction when you tilt the head, weakness or delay in the postural reactions of 1 to 4 limbs, and any change in mentation from dull to obtunded. Central disease also tends to get worse over 3 to 7 days instead of plateauing at 48 hours the way many peripheral cases do.
Head pressing means forebrain
Head pressing is not a head tilt. The cat stands in a corner and pushes its forehead into the wall for 5 minutes or more, often facing away from the room. That posture points to the forebrain: hepatic encephalopathy, a tumor, thiamine deficiency after 3 weeks of a fish-only diet, lead, or a viral infection. Hepatic encephalopathy is the one to screen for first, with bile acids and ammonia; a cat with a liver shunt can look normal for months, then press its head into a wall for 20 minutes. Head pressing, seizures, or a cat that walks into furniture goes to a vet today, not this week.
Toxins that make a cat circle
Ask what was applied or spilled in the last 12 hours. Permethrin, the flea product sold for dogs, causes tremors, hypersalivation and circling within 2 to 6 hours in cats, and a 1 ml spot-on is enough. Metronidazole at 50 mg per kg a day can cause vestibular signs after 5 to 7 days. Ethylene glycol, organophosphates, pyrethrin sprays and marijuana all produce ataxia with circling. Bring the package, and call a poison service before you wash the cat: the wash matters, but so does the timing.
The 5 item record
Write these down while you wait for the appointment, because memory loses them within an hour.
- Onset: exact time, and whether it was 1 event or 3 in the first hour.
- Direction and diameter: clockwise at 50 cm, for example, plus 1 video of 30 seconds.
- Feeding in the last 24 hours: how much eaten, whether the cat dropped food from 1 side.
- Litter box: clumps and urine volume, since a cat that cannot walk straight may also stop urinating.
- Exposure: any flea product, human medicine, plant or cleaner in the last 12 hours.
What the exam will test
Expect otoscopy of both ears, a 12 part neurologic exam, blood pressure, T4 and a blood panel. A cat with a head tilt and normal bloodwork often goes home on ear treatment for 7 to 10 days and improves in 3 to 5. If signs are central, imaging follows: MRI at 1,200 to 2,500 dollars, or CT at 600 to 1,200 if the budget is tight. Skull X-rays at 150 to 300 dollars miss most brainstem lesions, so ask what the scan will change before you pay for it.
When to see a vet
Today: head pressing, seizures, a cat that cannot stand, vertical nystagmus, or circling that started within 24 hours. Within 24 to 48 hours: a stable head tilt with a good appetite and no weakness. Same hour: any known exposure to a dog flea product, antifreeze, or a human medicine, plus 2 or more seizures in 24 hours. A cat that circles and also stops eating for 24 hours moves up the list regardless of how well it walks.
The first 24 hours
- Clear a 2 by 2 m floor, remove stairs and block the pool, and keep the cat indoors.
- Measure direction, diameter in cm, turns per minute and falls per minute.
- Film 30 seconds and note the onset time to the minute.
- Check the litter box and count urine clumps; 0 in 12 hours means an emergency visit.
- Collect every package applied in the last 12 hours and put it in a bag for the vet.
If the cat also breathes with an open mouth or makes a wheezing sound during an episode, read wheezing before the visit, since a cat in respiratory distress needs oxygen before imaging. Any product you find in the house goes on the toxin list check first, and a cat that has been circling for 3 weeks with a sore on 1 side of the face may have scratched an ear until it bled, which is covered under wounds that will not heal.
Terms mentioned in this article
Frequently asked
Is circling always a brain problem?
No, but it is always a neurologic sign worth measuring. Peripheral vestibular disease from an ear infection accounts for 60 to 70 percent of cases, central lesions and forebrain disease cover most of the rest, and toxins such as permethrin mimic both. A cat with a 30 to 60 cm circle and a head tilt is usually peripheral; wide 1 to 2 m circles with head pressing need a vet within 24 hours.
How urgent is head pressing?
It is a same-day sign. A cat that pushes its forehead into a wall for 5 minutes or more is showing forebrain disease, most often hepatic encephalopathy, a tumor or thiamine deficiency. Ask for bile acids and ammonia first, because a liver shunt can stay silent for months and then produce 20 minute pressing episodes with seizures.
What should I record before the vet visit?
Five items: exact onset time and number of episodes in the first hour, direction plus circle diameter in cm, food intake over 24 hours and whether food drops from 1 side, litter box output, and every product applied or spilled in the last 12 hours. Add a 30 second video shot from 1 m away with the whole body in frame.