I second the recommendation to test for pancreatitis (Spec fPL for lab assay on severity or SNAP fPL in-house test for Yes/No result). Vomiting, diarrhoea, gas and lethargy are all clinical signs that could be due to pancreatitis. I've seen several cats here - my own included - who had pancreatitis issues a short while after finishing insulin treatment. I wanted to keep giving Saoirse a daily microdose of insulin to provide a bit of support for her pancreas (she has chronic pancreatitis and she was running in the mid-higher part of the normal range not long after insulin treatment was withdrawn) but a specialist she was referred to put the kibosh on that and our own vets could not then prescribe for her. I'm still angry about that 18 months later; I had to watch Saoirse gradually deteriorate for the best part of a year before I could get another Lantus Rx for her.
If it does prove to be a touch of pancreatitis then it can be successfully managed with the right supportive meds. The sooner you get them in place the better; it can lessen the severity of a flare. Cerenia is good for nausea and vomiting in the first instance. For ongoing anti-nausea treatment and maintenance I can't recommend ondansetron highly enough. If it is a flare then pain relief may be needed (buprenorphine). A course of B12 injections helps a great deal. If appetite is an issue cyproheptadine is mild in effect. It is relatively short in duration of effect but you can give it up to 3x per day so it can give you much better control over the amount of appetite stimulation required (plus no risk of serotonin syndrome). It's important to ensure that Monkey is properly hydrated, too. If BG is up then it is better to reinstate insulin therapy as soon as possible. It's vital that you keep Monkey eating regularly; very small, frequent meals are better.
IDEXX pancreatitis treatment guidelines
Nausea, vomiting and appetite problems - symptoms and treatments
Cats going through a pancreatitis flare can look really,
really ill and it can be absolutely terrifying if the flare is severe BUT ... once they get the right supportive treatments in place it can be astounding how well they recover (been through two really bad ones with Saoirse but she improved enormously with appropriate treatment).
Just to cover all bases, make sure Monkey isn't constipated as this can also cause lethargy and vomiting (get vet to do a physical exam). Note: sometimes cats may get a little diarrhoea when they're constipated due to more liquid faeces getting squeezed round a 'stuck' stool. More information at
www.felineconstipation.org.
Make sure you also test urine TODAY for ketones (using Keto-diastix or similar). If you get a trace result call your vet for advice straight away. If you get anything higher than trace get Monkey to the vets
IMMEDIATELY for emergency treatment (to head off possibility of DKA).
Mogs
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