aww so sorry to hear about the loss of your first rabbit and the tough situation youre going through but it sounds like youre doing a great job and really keeping on top of things… at least worms are usually an pretty easy fix.. I wish I had any advice to offer but Goodluck with everything and I hope your bunny feels better soon!

 worms/parasites can explain gi tract issues too.    Antibiotics can also cause some tummy upset in some bunnies as well.  So it’ can be tricky.   Was the antibiotic given FOR stomach upset, or was the vet thinking something else was going on — some sort of illness or bacterial infection somewhere?  ( gi stasis can be a symptom of that just because when  a bunny is stressed or ill, it can cause an imbalance of bacteria in the gi tract but it’s not as common to give an antibiotic for gi stasis itself. .

This is a really good article, and please scroll down to the section too about using antibiotics FOR a gi issue, as I encourage you to discuss this with your vet. 

http://www.bio.miami.edu/hare/ileus.html  (Don’t let the title freak you out.  Pretty much everyone has had a bunny that has experienced gi troubles at LEAST once and it worked out just fine with good care. 

EDITED TO ADD:  I was so focused on giving you advice, that when I saw Tara’s post, i realized I did not offer my condolences for your other bunny.  I am sorry for your loss and I know this must be really scary for you now especially because of what you went through.  

I don’t think that your rabbit keeps crashing on you. Rabbits depend on us humans for their health and assurance. I”m sorry that he is going through this

So sorry about your first rabbit, my condolences.

From what I understand, diabetes is rare in rabbits and the only way you can control it is through diet.

I would say if you have all the tests done and still don’t have an answer, consider seeking a second opinion. Hopefully the stool sample will have some answers as well.

You can take the worm in- but you should also take a fresh stool sample in also. Some parasites are not visible to the eye and by checking the stool sample- they are checking for eggs of the parasites which are found in the stool. So it would be best to take both. It IS possible for a bunny to have a visible worm- like a pinworm which needs an antiparasitic (not an antibiotic) and also coccidia which needs a certain type of antibiotic.
Unfortunately it is not uncommon at all for bunnies to have intestinal parasites as they can be difficult for breeders (good and bad) to eliminate from the environment in a rabbitry. BUT completely possible to eliminate in a house pet following the steps recommended by your vet to prevent recontamination depending on what parasite or parasites.
My English Lop, Griffin, had coccidia when I got him. Had a stool sample checked, was positive, treated with Albon (prescription med) rechecked s amount of weeks after treatment, negative- all cleared up.

I’m so sorry for your loss but that’s wonderful he’s doing so well now and one whole week with no issues!! I agree-the parasites could really have been what was causing him to go into distress in the first place. In addition to giving that medication I would change the litter box every day or more often if you can and bleach it out each time. Many parasites are inhaled so if you can get the poopies out right away that would likely help.
Can they not give you an eyedrop without the dye test? My Noot had an eye ulcer-two dye tests-one to say ‘oh yes it’s an ulcer, here are drops’ and another to say ‘oh yes it’s cleared up’-but imho likely not necessary if they think it’s scratched they may just be able to give you the drops at any rate. They are also a can’t hurt might help type thing, and often around $10, so that might be doable depending on how your bills are going after so much emergency care.

You can use photobucket.com (That’s what I use-free and easy!) to post pictures-you just copy and paste strait from photobucket

They can give meds without staining the eye- but they will be an antibiotic type med with NO steroid/cortisone or dex. If you use an eye drop with steroids in an eye with an ulcer or scratch it actually inhibits the healing of the scratch or ulcer which is of course bad. So going with a more general eye drop could treat the eye- but not as effectively possibly.
For example- my kitten Melody is about 6 months old now. When I got her from the rescue she had an eye issue- her eye was even sewn closed at the time of spay to allow for better healing. I used antibiotic type eye drops on her thru the small gap in the lid and for a couple of weeks after the suture was removed. It never really got 100% and actually started to get worse- she was holding it more closed and with more frequency. So I took her into my vet- they stained the eye to make sure there was NO ulcer/scratch- and when that was clear they were able to prescribe a Neo/Poly/Dex eye drop- AB with steroid. An IMMEDIATE difference when switching drops- the steroid in the eye drop is able to address the issue of swelling and discomfort topically where the other eye drops could not. Best of all (sorry for you non US members)- Neo Poly Dex drops are on the $4 Target or WalMart med list and that list is VALID for pets. But so was her previous prescription of Tobramycin.