What is "head tilt?" The condition medically known as torticollis (Latin for "twisted neck") and sometimes as "wryneck" makes a rabbit's neck twist, causing the head to tilt sideways. Sometimes, torticollis is accompanied by nystagmus, a constant, involuntary movement of the eyeballs. The direction and nature of nystagmus can help your vet determine the cause of the torticollis in order to prescribe appropriate treatment.
Signs of torticollis may develop gradually or appear quite suddenly, but the result is the same: a bunny is walking around with her head on sideways.
In truth, head tilt is usually not only survivable, but treatable, though recovery may be gradual. Even a rabbit with a head tilt can live a happy, comfortable life as long as there is no pain, and the bunny enjoys eating, drinking, and being loved. I would consider euthanasia only as a last resort, if all attempts to treat the condition have failed, leaving the bunny in misery, unwilling to eat, drink or act normally at all. Remember that a permanently tilted head is not a symptom necessitating euthanasia! Many rabbits with their heads tilted at a jaunty angle are living completely happy lives, running and playing with all the vigor of their straight-headed bunny pals. The most important thing is to address the source of the head-tilt symptom. Once this is accomplished, improvement of the rabbit's posture will usually follow gradually, with physical therapy and exercise.
It is not uncommon for torticollis to appear suddenly. As with almost any illness, the more rapidly the cause of the problem is diagnosed and treated, the greater the chance for full recovery. If you do not already have a good veterinarian who is experienced with rabbit medicine, please use the House Rabbit Society Veterinarian Listings to find one in your area.
Successful treatment of the condition requires correct diagnosis of the problem's ultimate cause.
Sometimes, pus is visible inside the ear, and the vet can take a sample for identification. This will reveal
Although common pathogens associated with head tilt commonly include Pseudomonas aeruginosa and Pasteurella multocida, there are many others that also can cause ear infections or abscesses. Each species/strain of bacteria has characteristic sensitivity to certain antibiotics and and resistance to others. If possible, it is wise to identify bacteria so that the most effective antibiotic (or combination of antibiotics) can be administered.
Once the pathogen is identified, don't be surprised if your vet proposes to try a combination of antibiotics to kill the bacteria. A combination of antibiotics is often more effective at resolving an infection than a single one. It is especially important that your veterinarian be familiar with the specific needs of rabbits in terms of antibiotics, since some them (e.g., any oral penicillins such as amoxycillin, and any lincosamine antibiotics such as clindamycin) can be deadly to rabbits, even if they can be used safely in other species.
Whatever the prescription, it is important to continue to administer the full dose for the full course your vet has prescribed, even if signs of disease improve. Stopping antibiotic therapy before an infection is fully controlled can select the most resistant bacteria, since they will be the last ones to die when exposed to antibiotics. If antibiotics are removed too soon, only the most resistant ones will be left to reproduce and repopulate your poor bunny's head!
Unfortunately, ear infections and head abscesses, in general, can be difficult to treat. They tend to become "walled off" and are poorly supplied with blood vessels. This makes actually getting the antibiotic where it's needed a challenge. The vet may choose an antibiotic that has better penetration of such difficult antibiotics.
One antibiotic therapy that has proven very effective in many difficult torticollis cases caused by middle- or inner-ear infection is dual-acting penicillin injections. This combination of Penicillin-G (benzylpenicillin) (often combined with procaine, a local anesthetic) and Benzathine penicillin has resolved abscesses in some of our rabbits who had previously been deemed terminal and untreatable. Pasteurella tends to be susceptible to penicillins, but if the abscess is caused by Pseudomonas (or other penicillin-resistant bacterium), then penicillins will not be effective. A different antibiotic must be chosen.
While the antibiotics are doing their work, your vet might also prescribe other drugs to help restore balance and control the discomfort associated with vertigo. Meclizine can be helpful for controlling dizziness, though it will not work for every rabbit. If meclizine does not control the vertigo and nystagmus, your vet might prescribe a course of short-acting corticosteroids to reduce the inflammation interfering with the vestibular apparatus. We have found that these drugs can sometimes help restore normal posture even before the infection is fully cured. However, corticosteroids should be used with great caution in rabbits, as they tend to be more prone to the adverse side effects of these hormones than many other species.
It can sometimes take weeks or even months to completely cure an inner/middle ear infection. This may sound like a long time, but if supportive care is offered, and the rabbit continues to eat and drink normally and is still interested in life, then he's not ready to give up. The condition is disorienting, but does not seem to be painful. The illness is temporary, if hard to watch, but it's worth a course of supportive care to see your bunny happy and running around again.
The results of patient nursing a bunny through torticollis can be very rewarding. I have nursed several rabbits through torticollis apparently due to ear infection/abscess.
Mature E. cuniculi inhabit the central nervous system and renal (kidney) tissues of their definitive hosts, and infected rabbits showing signs of head tilt can also be suffering from renal compromise due to this parasite.
A number of articles on this putative pathogen can be accessed HERE.
At the moment, positive diagnosis of E. cuniculi infection can be made only upon necropsy, though histological results do not conclusively prove that the parasite was the cause of signs of illness.
A blood sample can be collected and sent to a laboratory to obtain a titer of E. cuniculi antibodies, produced by the rabbit in response to the presence of the parasite. However, a high titer does not necessarily indicate active disease; it says only that the rabbit has been exposed to the parasite at some time.
Benzimidazole drugs (e.g., oxibendazole, fenbendazole; [albendazole is NOT recommended, as it has been associated with acute death due to bone marrow damage in rabbits and other species]), readily cross the blood-brain barrier to inhibit the function of E. cuniculi's tubulin, a protein essential for the parasite's feeding and infection of new host cells. Suter, et al. (2001) reported that administration of 20mg/kg QD (once per day) of fenbendazole (which is metabolized to its active form, oxfendazole) was effective not only at preventing infection of rabbits by E. cuniculi, but also at eliminating signs of E. cuniculi infection in seropositive rabbits after four weeks of treatment.
Ponazuril is a drug developed for treatment of equine protozoal myeloencephalitis a horse disease caused by a parasite, Sarcocystis neurona, similar to E. cuniculi. Many veterinarians have been using this drug "off label" to treat E. cuniculi in rabbits, with anecdotal reports of success. I have been witness to one such case in our rescue bunny, Tilda. Tilda came to us with severe torticollis, but had no visible evidence of ear infection. We suspected that her tilt might be due to E. cuniculi. She was treated with fenbendazole and ponazuril concurrently for 30 days, and all traces of head tilt resolved completely, never to return.
At present, there is no treatment and no cure.
If the problem is believed to be caused by an intracranial abscess, with no pus to culture, your vet might wish to try dual-acting penicillin (as described above). Intracranial abscesses are often associated with dental infections. Because these often are populated by normal inhabitants of the intestine, antibiotic treatment can be particularly troublesome. We have found that dual-acting penicillin can combat these pathogens without entering the intestine and causing potentially life-threatening dysbiosis associated with oral penicillins and lincosamine antibiotics.
Physical Therapist Larry Gavlak shares his hints for physical therapy that helped his bunny (Boper) regain his balance. Larry has used the same technique on humans who had lost their sense of balance, and he simply translated and scaled it for bunny!
Treatment of head tilt is not only possible, but often successful and rewarding. It might help to realize that rabbits do not mourn over what might have been, nor what the future might hold. If your rabbit is willing to survive the moment, is eating and drinking and showing affection and interest in life (however dizzily), s/he deserves a chance to heal. It is so rewarding to see a head tilt bunny race and frolic as before, even if it takes several months of treatment and love.