At first glance, pain is not always visible in rabbits, and even experienced owners often fail to notice when their rabbit is suffering from chronic pain! For laboratory rabbit care, scientific research has been conducted on how pain can be recognized in rabbits. This scale can be used to detect illnesses and pain conditions and to correctly dose pain relief medication.

Important: Depending on the condition, usually only a few signs are visible, and rarely are many signs present at once. It is sufficient for one or two signs to be pronounced in order to recognize pain conditions.

One or two of the mentioned signs are enough to detect pain in the rabbit.

Facial Expression


Facial expression is mainly used to classify and recognize more intense pain conditions.

Experienced owners usually develop an intuitive sense over time of whether their rabbit is in pain. Nevertheless, it helps to know the signs: Train your eye by familiarizing yourself with the signs so you can recognize pain early.

Regarding the photos: These are part of a scale. The rabbit on the left is pain-free, the middle one is suffering from pain, and the rabbit on the right is in extreme pain.

The Rabbit Grimace Scale (RbtGS):
Squinting and narrowing of the eyes

The eyelid is partially or fully closed. If the lid covers more than half of the eyeball, it is considered a sign of extreme pain. The eyeballs may also shift back into the eye socket during pain, making them less prominent.

Cheek flattening

In pain, the tension in the muscles causes the rounded cheeks on either side of the nose to flatten, making the cheeks appear less prominent.

V-shaped nose

A pain-free animal has a U-shaped nostril, while in pain, it becomes V-shaped.

Whisker Position
Whiskers usually hang in a slight curve downward. In pain, they are stretched horizontally or pulled closer to the body. They often appear stiffer and less curved.

Ear Position

Animals in pain hold their ears very tightly against their neck and curl them, making the ear opening smaller

Back Arching
The back is a very informative indicator of pain. When in pain, rabbits sit with a more pronounced arch in their back, meaning the back slopes steeply downward, and the hind legs are pushed forward toward the front paws.

The Bristol Rabbit Pain Scale (BRPS)
How to use the BRPS:

  1. Observe the rabbit for 3 minutes.
  2. Quietly approach the cage and then assess the behaviors described in each category.
  3. Rate each category on a scale from 0 to 3 based on the behavior the rabbit displays during most of the observation.
  4. Calculate the total score, ranging from 0 to 21.
Categories0123
BehaviorThe rabbit is alert, looking around,
and responding to its surroundings,
OR the rabbit is sleeping.		The rabbit is awake but
shows little interest in its
surroundings.		The rabbit is apathetic
and does not respond to
the observer or its
surroundings.		The rabbit does not
respond to the observer or
its surroundings, even
when approached.
MovementThe rabbit is active and
hopping around, OR is relaxed
or sleeping.		The rabbit seems to
move hesitantly and
shows little activity.		The rabbit is inactive
and does not move during
the observation period,
except when approached.		The rabbit is inactive
and does not move at all,
even when approached.
PostureThe rabbit is resting in a
relaxed and comfortable position,
such as lying on its side or front
with its hind legs stretched out to
the side, or moving freely.
OR the rabbit is sleeping.		The rabbit is sitting
or lying on its belly
with its front legs visible.		The rabbit is sitting or
lying on its belly, with
its legs tucked under its
body and appears hunched.		The rabbit is sitting or lying
on its belly with its legs tucked
under its body, and its body appears
tense, stiff, and hunched. OR the
rabbit is pressing its belly against
the ground.
Ears
Keep in mind that rabbits
with floppy ears may
exhibit less
pronounced changes.		The rabbit moves its ears
freely and adjusts them towards
the direction of the sound. OR
the rabbit is sleeping.		The rabbit moves and
slightly turns its ears
toward the sounds.		The rabbit does not
move its ears noticeably
but responds slightly to
sounds (e.g., by turning its head).		The rabbit does not move
its ears at all and does not
respond to sounds, OR the
ears are flattened against the back.
EyesThe rabbit has its eyes open.
OR the rabbit is sleeping.		The rabbit has its eyes
half-closed.		The rabbit has its eyes closed.The rabbit keeps its eyes closed tightly.
GroomingThe rabbit grooms itself carefully.
OR the rabbit is sleeping.		The rabbit grooms
itself but is easily distracted.		The rabbit tries to groom
itself but has little energy.		The rabbit does not groom
itself at all.

Behavior

Certain behaviors can also be signs of pain:

Withdrawal:

  • Reduced activity or movement
  • Withdrawal from normal daily activities and hiding
  • Isolating from the group
  • Staring into space
  • Sensitivity to light (in case of eye conditions), squinting
Steep forehead (tucked head), tense body posture (crouching), and remaining motionless: Pain conditions can be recognized from a distance with a trained eye.

Tense Body Posture:

  • Frequent changes in body position, with none appearing comfortable
  • Crouching or unusual body posture
  • Possibly protecting a body part
  • Pressing the belly to the ground
  • Arched back

Movement:

  • Changes in movement patterns
  • Hind legs getting stuck at the edge of the litter box
  • Unusual movements

Reactions:

  • Decreased interest in the surroundings

Aggression & Intolerance:

  • Aggressive behavior (towards the owner, other rabbits, or other animals), usually directed towards either other rabbits OR the owner
  • Changes in group dynamics (intolerance, shifts in hierarchy…)
  • Altered behavior
  • Increased digging or destructiveness

Changes in Eating Habits:

  • Refusal to eat, loss of appetite, eating less, reduced appetite, changes in bathroom habits, inappropriate urination, fecal or urine stains on the hindquarters, reduced or no poop production

Attention to the Painful Area:

  • Licking, biting, or chewing at the wound or painful area
  • Focused attention on the wound or painful spot
  • Excessive grooming
  • Flinching or other reactions to touch or handling

Appetite: Some rabbits eat less or stop eating entirely (leading to weight loss) when in pain, especially with severe pain. However, many will still eat fairly well despite discomfort. If eating stops, smaller (hunger) stools may be produced or stool production may cease altogether.

Grooming:

  • Excessive licking/biting (self-mutilation) of a painful area, often at joints if the pain is joint-related; this can lead to hair loss or even wounds.
  • Neglect of grooming, unkempt fur
  • Cecotropes are not eaten by the rabbit

Physical Abnormalities:

  • Teeth grinding (which can also occur when the rabbit is feeling comfortable)
  • Increased breathing rate
  • Excessive salivation
  • Unkempt or saliva-soaked fur, bald spots caused by licking or biting
  • Dirty bottom


Ernie has injured rabbits (severely) multiple times and had to be reintroduced. Despite being treated by rabbit-savvy veterinarians, no one thought to X-ray his ears or perform a cytology test. It wasn’t until much later that the chronic ear infection was diagnosed. By this time, he had already lost his position in the hierarchy due to the chronic condition and had become more submissive. Aggressive behavior (along with uterine disorders) is often related to pain in the head area (ears, teeth).

Proper Pain Treatment


Rabbits are not simple pain patients. On one hand, pain can only be recognized by experienced and specially trained individuals. On the other hand, due to their fast metabolism and unique physiology, they respond to pain medications somewhat differently than most other pets. Therefore, it is even more important to correctly interpret pain expressions and behaviors, so that pain medications can be properly adjusted.

Tips for Pain Management:


Rabbits require higher doses of pain medication than dogs and cats. For example, the effective dose of Meloxicam for rabbits is 1 mg/kg/day (manufacturer’s recommendation, studies, see below), which is five times higher than the dosage for cats or dogs. The manufacturer may provide information to the veterinarian, or specialized literature can be consulted. The standard dosage for carnivores is usually not sufficient for rabbits.

It is most effective to use a combination of two painkillers, as rabbits respond much better to this approach.
The total daily dose should be divided into as many smaller doses as possible, since rabbits metabolize medication very quickly, causing the drug level to drop rapidly.

Careful observation and reference to this pain scale will help adjust the pain medication properly, ensuring the rabbit remains pain-free.

Hidden Causes of Pain


Sometimes, it can be difficult to identify the causes of pain, as some illnesses are not immediately visible in animals. While humans can tell a doctor where it hurts, a rabbit can only display pain signals, leaving the exact cause and location of the pain unknown.

In such cases, it is even more important to consult a knowledgeable, experienced veterinarian. The link provides a list of vets sorted by postal code. It’s better to travel a little farther to find a vet who is familiar with rabbits than to choose one who may not have the necessary expertise.

The vet will begin by performing a thorough general examination to gather initial clues about a possible illness. They will then use diagnostic methods to determine the underlying cause. X-rays and blood tests are often required to diagnose the condition.



This rabbit exhibited aggressive and withdrawn behavior and was returned to us due to compatibility issues within the group. Neither the owner’s veterinarians nor our own vets (including specialists) were able to identify the cause. It wasn’t until much later that his head was X-rayed due to a one-sided nasal discharge. He was diagnosed with a severe, bilateral ear infection and tooth root disease.

This rabbit exhibited aggressive behavior towards other rabbits for years, but was the sweetest bunny towards humans. Despite numerous vet visits, no cause for the pain-related behavior was found. Eventually, she was spayed, even though the ultrasound showed no abnormalities. Her uterus was normal, and unfortunately, her behavior did not improve. It wasn’t until a lump on her lower jaw was palpated that her suffering became apparent, and the X-rays revealed the cause: severe tooth root disease with an abscess! Dental issues are particularly painful for rabbits and often cause extreme discomfort.

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