singapore rabbits

nystagmus in rabbits, what it tells the vet

updated 19 May 2026

if your rabbit suddenly starts rolling, falling to one side, or has eyes that flick rapidly back and forth, you are looking at vestibular signs. nystagmus, the involuntary rapid movement of the eyes, is one of the most diagnostic of those signs. in Singapore, E. cuniculi infection rates in pet rabbits are high, and the city’s heat and humidity add extra physiological stress to an already distressed animal. exotic vets here are also relatively scarce; most neighbourhood clinics focus on cats and dogs. knowing what nystagmus means, and what it tells the vet, helps you act fast and arrive at the clinic with useful information already in hand.

what nystagmus actually looks like

nystagmus is an involuntary, rhythmic movement of the eyes. your rabbit is not doing this on purpose. the eyes snap rapidly in one direction, then drift or reset, over and over again. this is different from a rabbit tracking a moving object. the movement happens even when your rabbit is completely still and nothing in the room is moving.

the movement can be horizontal (eyes moving left and right), vertical (up and down), or rotatory (a circular or diagonal flick). rotatory nystagmus is especially significant. a vet will note the direction carefully as a first diagnostic step.

nystagmus can also be constant or positional. positional nystagmus only appears when the rabbit’s head is moved into a specific angle. that distinction is a specific clinical clue. if you can safely observe which type your rabbit has before the vet visit, mention it.

what causes nystagmus in rabbits

nystagmus arises from a disruption to the vestibular system, which controls balance and spatial orientation. the vestibular system has two main parts: the peripheral component, meaning the inner ear and the eighth cranial nerve, and the central component, meaning the brainstem and cerebellum.

a problem anywhere along that chain can produce nystagmus. the most common causes in Singapore rabbits include:

  • inner ear infection (otitis interna): bacteria travel from the outer or middle ear inward. Pasteurella multocida is a common culprit in rabbits.
  • E. cuniculi (Encephalitozoon cuniculi): a microsporidian parasite that infects brain tissue and kidneys. it is the leading cause of sudden vestibular disease in Singapore pet rabbits.
  • stroke or ischaemic vestibular episode: a sudden vascular event in the brainstem. more common in older rabbits.
  • head trauma: a fall or impact can trigger acute vestibular signs immediately or hours later.
  • middle ear mass or polyp: less common, but possible in rabbits with a history of recurrent ear problems.

knowing which cause is responsible changes the treatment completely. that is why a vet visit is not optional when nystagmus appears.

what the direction of eye movement tells the vet

the direction and character of nystagmus is one of the first things a vet assesses, because it helps localise the lesion.

with peripheral vestibular disease (inner ear), nystagmus is usually horizontal or rotatory. the fast phase, the quick snap of the eye, typically points away from the side of the lesion. if the right inner ear is infected, the fast phase tends to point left. this pattern is a useful starting clue, though not absolute on its own.

with central vestibular disease (brainstem or cerebellum), nystagmus can be vertical. vertical nystagmus is a red flag. it almost never comes from a peripheral problem. a rabbit showing vertical nystagmus needs urgent assessment.

important: vertical nystagmus points toward a central lesion. do not wait overnight. contact a SG exotic vet immediately.

rotatory nystagmus sits in a grey zone and can appear in both peripheral and central disease. the vet weighs the direction alongside other signs: is there a head tilt, and which way does it lean? can the rabbit right itself when placed on its side? is there facial nerve involvement or abnormal eye positioning? all of these findings together form the clinical picture.

nystagmus and E. cuniculi in Singapore

E. cuniculi deserves its own section because it is so prevalent here. studies in companion rabbit populations across Southeast Asia have found seropositivity rates, meaning the rabbit has been exposed to the parasite, often exceeding 50%. many rabbits carry it silently until a stressor triggers active disease.

the classic E. cuniculi presentation is sudden onset: head tilt, rolling, nystagmus, and sometimes seizures. it can look catastrophic in the first 24 hours but often responds well to treatment if started promptly.

in Singapore’s climate of 28 to 32 degrees Celsius and 70 to 90 percent humidity year-round, rabbits already run physiologically warmer than in temperate countries. a vestibular episode combined with a warm HDB flat adds heat stress on top of neurological stress. keep the AC on if your rabbit is showing any vestibular signs. a room temperature of 22 to 24 degrees Celsius is appropriate during recovery.

the cost of an E. cuniculi workup at a SG exotic vet, as of 2026, typically ranges from SGD 150 to SGD 400 depending on the tests ordered, including blood serology, urinalysis, and consultation fees. a full MRI to rule out a central lesion can run SGD 800 to SGD 1,500 or more, and not all SG clinics have MRI access for rabbits.

what the vet does during the examination

when you bring in a rabbit with nystagmus, the vet will take a full history first. they will ask when you noticed the signs, whether onset was sudden or gradual, whether there has been any prior head tilt, and whether the rabbit has been tested for E. cuniculi before.

the physical examination includes:

  • observing the direction and character of nystagmus at rest and with head repositioning
  • noting any head tilt and which direction it favours
  • assessing whether the rabbit can right itself when placed on its side
  • examining the ears with an otoscope for infection, discharge, or mass
  • testing cranial nerve reflexes to check for signs of central involvement

after the clinical exam, the vet may recommend blood tests including an E. cuniculi serology titre, a complete blood count, and biochemistry. imaging may follow; ear X-rays can assess the tympanic bullae for infection or fluid, and MRI can evaluate the brainstem directly.

treatment depends on the diagnosis. peripheral vestibular disease from an ear infection typically responds to antibiotics and sometimes anti-nausea medication to help the rabbit manage motion sickness and maintain appetite. E. cuniculi requires fenbendazole, a prescription antiparasitic. your vet will determine the dose and the duration of the course. central lesions need more aggressive management and carry a less certain prognosis.

what owners often get wrong

mistaking nystagmus for a seizure. a rabbit with rapidly flickering eyes is not necessarily seizing. true seizures usually involve muscle rigidity, paddling limbs, loss of consciousness, or tonic-clonic jerking. nystagmus alone is a vestibular sign, not necessarily a grand mal event. that said, E. cuniculi can cause both at once, so a vet still needs to assess quickly.

assuming it will settle on its own. nystagmus is not a wait-and-see sign. it indicates active vestibular system disruption. the sooner a diagnosis is made and treatment started, the better the chance of good recovery. early treatment is almost always less expensive than managing a prolonged or worsening condition.

diagnosing E. cuniculi at home because the symptoms match. E. cuniculi is common in Singapore, yes. but nystagmus and head tilt can also come from a serious inner ear infection, a stroke, or a growing mass. treating for E. cuniculi without ruling out other causes risks missing a condition that needs a different treatment entirely.

not mentioning prior episodes to the vet. if your rabbit had a mild head tilt months ago that resolved, say so. prior vestibular events can point toward E. cuniculi recurrence or a chronic ear problem. that history changes the diagnostic picture significantly and helps the vet choose the right tests first.

community-sourced information here is not veterinary advice. for any health concern see a licensed SG exotic vet.

community-sourced information, not veterinary advice. for medical issues, see a licensed SG exotic vet — start with our vet directory.

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