I'm very sorry to hear that Henley is feeling so poorly.
Your vet should be able to run an in-house SNAP fPL test to get a Yes/No result for pancreatitis. (The Spec fPL quantative test needs to be sent to IDEXX and it can take days to get the result.)
Here are the
IDEXX guidelines for pancreatitis treatment. I recommend you read them so that you'll have a guide to what your vet should be doing to help Henley - particularly for anti-nausea and appetite stimulation support.
The anti-nausea support is key because the appetite stimulation meds won't be very effective without it. Cerenia injectable may get to work a bit faster but from my experience it is not quite as beneficial as ondansetron. The ondansetron can take a little time to build up its effect (e.g. 2 to 4 doses) but the Cerenia might tide Henley over for that period. From my own experience and having read stories of other cats here with nausea problems (with pancreatitis or DKA) I think vets sometimes drag their heels about getting the proper anti-nausea support in place so I'd recommend you really keep on the vet's case if they're not moving fast enough with this because it can make a
world of difference to getting a cat to eat.
If the vets haven't yet given Henley a B12 injection ask them to initiate B12 support ASAP per the IDEXX guidelines. B12 can help with appetite and also give a poorly kitty a general and much-needed boost.
I am assuming that the vets will be giving hydration support. Restoring proper hydration levels can help a great deal, too.
I note Henley has lost a lot of weight. Maybe the vets could give some type of recovery food which is calorie-dense to Henley? If she's eating only small amounts then the more calories they can pack into that amount the better. If the carbs are higher they should be able to work Henley's insulin around the food.
The other thing to ask your vets about is a feeding tube. With the weight loss I don't know whether Henley would be a candidate for anaesthesia but if she is then according to Dr Lisa Pierson of catinfo.org it is better to place the feeding tube sooner rather than later.
Here is Dr Pierson's article on feeding tubes. Again, I recommend you read this straight away so that you'll know which treatment options may be available to help Henley and you can then discuss them with your vets.
Assuming that it is pancreatitis, note that a cat can look very poorly at the height of a pancreatitis flare but if you can get the right treatments in place quickly they can help a lot - and somewhat faster than one might at first think.
Sending prayers and healing thoughts for Henley and

s for you.
Mogs
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