Head Tilt: Causes and Treatment
Editor’s Note: This article is not meant to help the lay person diagnose and treat head tilt, and any rabbit showing signs of head tilt should be taken to the vet without delay.
A bunny with a head tilt is a very sad sight. Are we doing the right thing to keep him alive? Is he still happy? Will he ever be cured? These are the questions for most in our minds when one of our rabbits suddenly develops this problem.
- Middle/inner ear infection (otitis media /interna)
- Stroke (cerebrovascular accidents)
- Cancer (neoplasia)
- Cervical muscle contraction
- Cerebral larva migrans
A diagnosis as to the cause of the problem is frequently made after elimination of other possibilities. Lets examine these one at a time, starting with the one thought to be most common:
Inner ear infection
An inner ear infection may have started with an outer ear infection, which remained unnoticed and untreated and gradually worked its way into the inner ear, or with a middle ear infection, which resulted from an upper respiratory infection. Or it may have arisen from bacteria in the nasal cavity or bloodstream. A radiograph of the head may help determine if the middle ears are affected. Some of the bacteria which have been cultured from ear infections are Staphylococcus sp, Pseudomonas aeruginosa, Pasteurella multocida, Bordetella bronchiseptica, Proteus mirabilis, Streptoccus epidermidis, Bacteroides spp. and Escherichia coli.
Treatment needs to be aggressive and prolonged. If exudate (pus) is found deep in the ear canal, a culture and sensitivity should be done in order to determine the bacterial agent and which antibiotics will be most effective in eliminating the infection. However, if it is impossible to access the bacteria in order to do the culture, many veterinarians will opt to treat with one of the antibiotics usually successful in curing an inner ear infection, such as enrofloxacin, chloramphenicol or penicillin G procaine with benzathaine. If no improvement is noticed after 4 weeks, a change in antibiotic is recommended.
If attempts to clear the infection with antibiotics appear to be failing, the veterinarian may suggest ear surgery to be able to obtain a sample for a culture and sensitivity, to remove exudate, and to provide drainage. Antibiotics need to be withheld for 3 days prior to obtaining a culture. One treatment includes leaving a drain. However, the exudate that rabbits produce is frequently very thick and does not drain.
If the head tilt is extreme, a steroid may be prescribed in an attempt to reduce the inflammation. If the rabbit is not eating or drinking, the doctor may recommend that fluids be administered subcutaneously and food given orally by syringe.
Although middle and inner ear infections reportedly have a poor cure rate, I know many cases of success in getting rabbits through this illness. The “secret” is long term antibiotics, frequently a minimum of 30 days. However it may be necessary for a rabbit to be on antibiotics for 6 months or even for the remaining years of his life. This treatment in conjunction with a loving and supportive environment can provide the rabbit with a good quality of life even if the disease cannot be completely eradicated.
Stroke is usually suspected on the basis of physical signs. Imaging to diagnose this problem is available to humans but difficult to arrange for companion rabbits. As in humans, acerbrovascular accident can kill, but if it does not, then the rabbit may initially be left with one side of his face, and perhaps one entire side of his body affected. One side of his face will droop, he may drool, and one eye may not function properly. He may not move normally or may move in circles. Function usually will slowly return over a period of months. Almost three years after a stroke, one of my rabbits has only a slight tilt to his head, unnoticeable, unless pointed out. Benny just looks a bit quizzical.
Care for a bunny who has suffered a stroke involves nursing him through his difficulties in eating, drinking and moving. Antibiotics do not help these cases, but sometimes are given to help rule out infection. Acupuncture should also be considered in treatment of these cases.
A blow to the face, neck or head can result in an injury to the brain which can cause the rabbit to have a head tilt. Trauma even could result from a panic reaction. Depending upon the severity of the trauma, an anti-inflammatory might be helpful to speed recovery.
Tumors occurring in the brain, neck or ear could produce a symptom of head tilt.
Cervical muscle contraction
A “muscle spasm” could cause a temporary head tilt. This situation will resolve itself once the muscle is relaxed.
Encephalitozoon cuniculi, a protozoan parasite, can cause brain disease (meningooencephalitis and microscopic cysts), and can result in paralysis anywhere in the body, since every part of the body is controlled by a specific part of the brain. (See the HRJ Vol. III No. 2 for a detailed description of this parasite.) Frequently there are signs preceding a head tilt caused by E.cuniculi such as tripping, dragging of feet, tipping over. These symptoms may have appeared and then vanished weeks or months prior to the head tilt. A blood test for antibodies to E. cuniculi can tell whether your rabbit has been exposed.
Cerebral larva migrans
Baylisascaris spp are round worms which live in the intestine of raccoons and skunks. A rabbit may acquire eggs from these works by eating grasses, food, or bedding contaminated by feces. Larvae hatch from the eggs and migrate into the brain, where they live and grow and destroy brain tissue. There is no known cure for this invasion. Ivermectin probably does not penetrate the brain in sufficient quantities to kill the larvae, although it may kill them before they reach the brain.
This could be caused by ingestion of lead, found in paints or imported pottery, or ingestion of a toxic plant such as the woolly pod milkweed.
Caring for a rabbit with head tilt
Regardless of the cause, most cases of head tilt have similarities.
The “down” eye (the one facing the floor) will usually not close and will require eye ointment to keep the eye moist.
Lack of balance is what causes rabbits to “roll” and be unable to stand, so I try to pick them up as little as possible. When you must pick your rabbit up, hold him securely against your own body, to help him feel as stable as possible. Depending upon the size of your rabbit you can usually figure out how to confine him to a smaller space (perhaps a sweater box with the higher sides). Place one of the synthetic sheepskin rugs (that allows urine to pass through but will keep the bun dry) on the floor of the cage or box, and then place rolled towels or small blankets to help prop him up, so that he will be less likely to roll when he loses his balance. A stuffed toy bunny friend also helps.
Most rabbits will keep eating but may need to be hand fed with lots of sympathy with every bite of food. He may not want his pellets, but he will usually eat a variety of fresh green veggies, carrots and fruits if you hold them for him. It may help to switch from timothy to alfalfa hay to encourage him to eat lots of roughage.
If your rabbit decides to decline food, you will have to be ready to syringe feed him. There are many recipes for syringe feeding and you can be fairly creative. The primary point is to get food into his stomach so that his gut doesn’t stop moving, which would add further complications to the process of getting him well. A sample recipe might be pellets mixed with 2 parts water, mixed garden baby food, some banana, some powdered acidophilus, some apple sauce (some of whatever he usually likes that has a strong taste). Feed him as frequently as possible throughout the day, and as much as you can get down him at each feeding. When he clenches his teeth and won’t swallow, stop for awhile and try more later.
Winning or losing the fight
While many cases of head tilt can be successfully treated, others cannot. Blackberry, a wonderfully large 3-year-old French lop, was adopted by a rabbit-loving family and lived happily in her humans’ two story house. Three years later, Blackberry was diagnosed with an inner ear infection. She was on antibiotics for months and went through various periods of syringe feeding. She was getting better all the while and then suddenly had a stroke. She fought that for another month and then died after another stroke. The postmortem exam showed that the inner ear infection she was fighting was almost cleared up. We don’t know why she also suffered a stroke, but Blackberry was a brave and valiant fighter, unwilling to let go of life without a battle.
Regardless of the cause, sometimes a rabbit who survives will be left with a slight head tilt for the rest of his life. I’ve found that while the rabbit will adjust rapidly, his caregiver is the one who may have more difficulty accepting the “cosmetics” of the situation. Rabbits are mighty fighters and you can help him in his fight by offering lots of sympathy and carrots.
By Sandi Ackerman, in consultation with Barbara Deeb, DVM, MS
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