I've mentioned a few times on here about a guy who is on another forum who has extensively researched EC. This is the general gist of what he says.
EC does not directly cause head tilt. EC batters the immune system, which means the bunny can not fight off things like infections. Head tilt is generally caused by infection (but obviously there are other reasons too), and whilst that might be secondary to EC, it is not EC that causes the head tilt-it is an infection.
He also says that the Fenbendazole does not penetrate the blood brain barrier (those are the words he uses) and so can not iradicate the parasite EC in the brain, thus making it useless in active cases of EC. He has progressed onto using a different drug which is showing more promise, he says.
He also says to treat head tilt aggressively to avoid it progressing further into the ear and then into the brain. For that you will need more effective drugs than Baytril. Your bun will also probably need Metacam. Maybe read Angie65's thread on this page as to more things that are available.
A head can have a residual tilt (depending on the cause and the solution), but it should improve a great deal if its an infection, and is beaten. All rabbits differ with this.
This is Tilly's head tilt story. Not sure if it was be useful, or not, for you, but it may be.
Tilly was seized by the RSPCA officers from someone who was refusing to get her treatment. At that time she lived with a guinea.
When she arrived at the RSPCA they didn't know what to do for head tilt so Panacured her (funnily enough, to no effect). She had a 3-4 o'clock tilt, and arrived in August 2008. After she had been at the centre for two months (and tilted for a great deal more, but the amount is unknown) I fought to bring her home as a foster knowing that I would be willing to try different things with her and fight for her because I knew there was so much more.
The centre thought she needed someone who would mother her, and I sort of thought she needed someone who could stimulate her. I compromised and gave her both. I bought her home and bonded her with Summer (who would definitely stimulate her) and Roger (who is a mother hen), my other two fosters.
I took her to my vet along with a big blurb that Randy (ra7751) had written about head tilt. I wanted Zithromax for her but my vet had never heard of it, nor used it, but picked up on Convenia that Randy had written about and said he had it. I had never considered using it so had to make a spur of the moment decision based on my trust for Randy's info and also my vets ability to treat Tilly[highlight= rgb(255, 255, 136);] if anything went wrong. Thankfully I made the right decision.
The dosage that my vet used for Convenia was as it was labelled (I believe that's what he said). He said it's given to cats by their weight, and that is what he did for Tilly. We started off giving it every two weeks (which is how it is dosed in cats), but it became clear on day 2 it started to work, on day 9 it stopped working (it was easy to see because we were using it for head tilt so we could see the improvement in her head and alspo in how she behaved). We gradually cut down the time in between injections and found that once a week (every seven days) worked perfectly for her and she was kept on that for 2 months of weekly injections. It changed her life.
The hardest thing with Convenia is that because there is a long time inbetween injections if there are any side effects you have to ride the week out as best you can. The risks seem to mainly be gut issues (cecal dysbosis, chronic diarrhoea, etc) and there is not way to stop it once the drug has been injected. With Tilly, we saw no side effects at all. We did use Fibreplex during that time until we were sure that she was going to show no side effects. That is basically giving her additional fibre and can potentially be useful in some gut situations but not others (I personally don't think it should be used in a blockage situation, but in this situation I had no issue with it at all and would use it again).
When Tilly arrived she could go up onto things, but not get back down, when she looked down she would just roll, she didn't move her ears, she couldn't stand up on her back legs and periscope, she couldn't clean one back leg, she couldn't put her head straight and certainly couldn't tilt it over the other way. She had nystagmus (eye scanning) when we picked her up, she would sometimes roll and mostly ran round in circles.
Tilly was on Convenia for two months. Each week me and my vet discussed her improvement and then when we plateaued and saw no further improvement we gave her I think it was three further weeks on the Convenia to consolidate all that we had battled against.
During the time she improved we started to see things like she could clean both back feet, she started to turn and listen with both her ears, she didn't have nystagmus when she was picked up, her head straightened from roughly a 3-4 o'clock tilt to a 1 o'clock tilt to upright, she could just down from things, albeit a bit cautiously sometimes, we never saw another roll after treatment started, she ran faster, jumped higher and we even saw a half binky effort, which was so funny, she could run in straight lines and all sorts. She went from being a disabled buny to a regular bunny but with a funny head because she can now do everything that all other bunnies do.
Alongside all the treatment I gave her physio using pellets and pear (and later a wider variety of food when I was sure what she could tolerate) and also gave her daily or every other day neck massages, and she also liked a heat source to lay her neck on so sometimes I used those too.
A characteristic of Tilly that kept her fighting through it all was the fact she is so VERY stubborn, and boy does she know her mind. That shows now because sometimes she refuses to do something, or believes she can't, so just doesn't try, but now I know it's not due to her head tilt, it is due to her very stubborn nature.
This is Tilly as she is now, 8 months after finished her treatment. The video shows her periscoping (for food), also turning her head the other way (also for food), shows how she sleep, shows how she cleans herself properly, etc. She was very obliging