Hello and welcome. My name is ***** ***** I'm a biologist with over 40 years of experience raising and showing rabbits. I'm sorry to hear that Missy has had a problem.
This does sound like she had a seizure. Seizures in rabbits can be triggered by a number of different conditions. A toxin is one possibility. Some common toxins are found in painted surfaces of cages (if the rabbit chews them), food contaminants, certain plants, and even food bowls and water bottles (again if the rabbit chews them.) You can probably rule toxins out, but do check to see if Missy have been chewing on anything in her cage or around the house.
Severe pain can cause seizures. There are forms of burrowing mites that can get into the skin and cause excruciating pain. The mites are not visible to the naked eye, and many times don't even show up when a vet does a skin culture. Seizures are one sign of a heavy infestation. Before Missy got sick, did you notice her scratching or shaking her head? Is she shedding excessively? Either of these things might be a further indication of mites. Treatment is with ivermectin.
A common protozoan called Encephalitozoon cuniculi is another possible cause of seizures. It often causes what is called head tilt, where the rabbit holds its head to one side, loses its balance, and perhaps travels in circles. But, it can also cause seizures. There are several drugs that are used against this parasite, with ivermectin being one of them.
In older rabbits, a brain tumor can also cause seizures.
These are some of the more common possibilities, but there are others. My first recommendation to you is to find a vet who specializes in rabbits. This link will take you to a directory of them:
If none are close enough for you to visit, ask your vet if he/she would be willing to consult by phone with one of those vets to reach a diagnosis and decide on treatment. Yet another possibility is to contact a veterinary teaching hospital. They usually have a specialist on staff. Here is a directory:
The following is a page you'll want to look at. It lists the possible causes of seizures in rabbits. If you can't get to a rabbit-experienced vet, you could print out this page and take it to your present vet. That would give them a starting point.
If you have further questions, just let me know. I hope this will turn out to be an isolated incident and Missy will be fine.
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