Hyperthyroidism without weight loss?

My 11-year-old cat was diagnosed as "borderline" hyper-T on March 7th. At the time, they said it was just something we needed to watch. She also has FLUTD/IC and renal insufficiency. Well, this last week I have seen a completely different cat. For the past week, she has been completely ravenous and hyperactive, especially at night. I know that these are primary signs of hyper-t, but the only other sign she does not have is weight loss. She was 15 lbs on 3/7 and still 15 lbs this morning. I don't know if this is enough time for weight loss with hyper-t.

I have a call into my vet but wanted to know if anyone here had a hyper-t diagnosis without the initial weight loss. Some other things to consider are that she is currently being treated for a UTI. Here is what she's been taking since 3/7:

Zeniquin (antibiotic)
Reglan (motility/nausea)
Cosequin
Buprenex as needed for pain
Started eating Hill's k/d

I thought maybe one of these was causing the problem, but none of them have these side effects listed. Also, last night I tried giving her the buprenex thinking that maybe she was yowling from pain, but this didn't stop the behavior. Any ideas?

Thanks!

Do you know what her T4 was?

Vaguely remembering something scary about Reglan I looked in my pet drug book first. Found "behavior changes" mentioned under possible side effects.
So then I looked online. Found this:

http://www.petplace.com/drug-library...lan/page1.aspx

There have been occasional reports of changes in behavior and mental states. Cats may become very anxious, bordering on frenzied.

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http://www.justanswer.com/questions/...ts-reglan-cats

In cats the prime side effect is behavior changes. It can make cats very restless and excitable.

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Thanks Violet! She starts tapering down on her Reglan in a couple of days so hopefully I'll see some improvement. I never heard from the vet's office today so I'll try again tomorrow. They called me with the T4 results last week but I forgot to write it down so I'll ask them tomorrow.

The only thing I don't understand is the ravenous appetite. Perhaps that's just her way of dealing with all of the extra energy/nervousness? Now that I think about it, I give her the Reglan at night so maybe that is what's going on. I'll wait and give her the dose in the morning and see how she does tonight. Thanks for pointing that out!

Also, you won't see weight loss until her metabolism is ramped up to a point where she can't/doesn't take in enough calories to compensate for the weight loss. The ravenous appetite could definitely be a symptom of the elevated T4 level and as long as she can take enough food in, she won't necessarily be losing weight. That doesn't mean that the high T4 isn't doing other damage though. Since she is exhibiting new symptoms, definitely talk to the vet.

Okay here's a quick update. It turns out that her T4 levels were actually in the normal range. The tech just said that it's on the higher end for an older cat, so it's something that we should keep an eye on down the road. She definitely is not leaning towards hyper-T yet.

Also, I discontinued the Reglan last night and things were a bit better. She made it until 5:00 a.m. before her hunger rampage began. Two nights ago it was 1:00 and night before 2:00 so there is some improvement. I'm going to keep her off of it another day and see how it goes. The tech told me that if she doesn't continue to improve over the next couple of days to call them back and we'll figure out the next step.

Thanks for both of your responses. They're both extremely helpful!