? - Very bizarre: serotonin syndrome versus unusual reaction to lower numbers??? | Feline Diabetes Management Board

? Very bizarre: serotonin syndrome versus unusual reaction to lower numbers???

Elizabeth

Elizabeth

Member
This is long. I apologize. But it's complicated.

As Jonah has IBD, he has gotten Mirataz + ondansetron pretty regularly for 3 years. Usually I only have to give Mirataz every 3-5 days, but usually ondansetron daily. No issues.

Since Jonah has been on Lantus, I've had a lot of problems with him when his glucose was low normal or when things were bouncing. He wasn't eating well during those periods.

Last week, on 6/25, I gave Mirataz, and then gave it the next 2 days as well. Also ondansetron. Now ondansetron is in a similar class, but they are routinely given together and I have done so for 3 years. I did not exceed the dose on the packages or what my vet had told me to do. It is unusual for me to gove it 3 days in a row, but doing so should not have caused a problem.

By the 3rd day (27th) he was acting very sedated. I stopped both drugs. Something similar happened a few years ago with simbadol--we figure he is just sensitive to some drugs???

Trouble is that even though he was off the drugs, things got worse. By Sat (28th) he was no longer just acting sedated--he was disoriented, confused, ataxic (stumbling). He wanted to do nothing but stumble around the house aimlessly, running into things and getting stuck behind furniture. Reminded me of a sundowners dog.

I got scared Sat night about serotonin syndrome and took him to the ER. There is no test for serotonin syndrome, but they ran labs (unremarkable), checked his heart and BP (normal), etc. His glucose was 72 when we went in and 273 5 min later once they started messing with him. So there was no discussion of hypoglycemia.

They said it probably was serotonin syndrome, and that he should get better now that he wasn't on the meds. They said it was really bizarre, since he wasn't overdosed, but we had no other ideas.

The behavior continued. He won't settle, barely seems to know who I am, is disoriented, and just stumbles around. I keep losing him and finding him with his head stuck behind the fridge, frozen in place, or stymied by the rungs on the chair legs, unable to figure out how to get over them. It is TERRIFYING. He is literally a zombie.

Sun I got really scared and returned to the ER. Vet called the pet poison control folks, as I had read that cyproheptidine is used to treat serotonin syndrome. But it has risks and since his heart was still OK (SS can affect the heart) they felt it was safer to keep waiting rather than add another med.

But it's not better. Might even be worse. Sleep is something I can no longer do. Neither of us can. Note that I was not told to do ANYTHING after either trip to the ER other than keep on running SQ fluids just to be safe (which I was already doing, due to his not eating well).

Here's the thing though: Right when I was giving the Mirataz, something else was happening. Jonah's dose was increased to 2.5u, and his glucose started going down and surfing lower. And his symptoms are EXACTLY what are described for hypoglycemia.

Obviously his numbers aren't clinically hypo. But what if he is weird?? I mean, I know he IS. Is there any world where this behavior could be attributed to normalizing glucose? Should I lower the dose and see if he is better surfing higher?? Give some Karo and get the glucose up?

I cannot ask him to live as he is for long. I hate seeing him like this and know he is miserable. I am a sleep-deprived, panicked, losing-my-mind mess. And my kitty has gone from personable and loving to a terrifying stranger zombie cat.

Help. 😪
 
I do have a blood ketone monitor and get 0.1-0.3 whenever I test (most recently yesterday).
 
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Hi Elizabeth—
I’m sorry no one has responded. It’s not that no one cares … more likely no one has any concrete experience or suggestions.

I’ve read and re-read your posts a few times. I don’t have any first-hand experience (that I’m aware of anyway) with serotonin syndrome in cats. But I will offer a few thoughts.

First, a few questions …
- has anything at all changed recently in your home? Any chemicals sprayed for bugs, new essential oil diffusers, medications spilled, flea/tick medicine applied, anything whatsoever?
- has Jonah had any injections (other than Lantus) or supplements recently? Solensia perhaps? Vaccines? SubQ fluids (what type, how much/often)? Is he on any other medications or supplements?
- is Jonah indoor only?
- has anything changed with his food? Does he hunt and eat bugs or prey?
- are you certain that he can see? Are his pupils constantly dilated?
- how much mirataz were you using? How much ondansetron and how frequently?
- when he clocked those lower BG numbers on the Libre, I see you re-tested with a human meter. Did you test again before an hour passed to ensure he didn’t go even lower in the interim?

And just a thought … given that you felt the Mirataz was warranted daily rather than every few days, I wonder if something was already brewing and he was about to go “off the rails”anyway. Maybe the Mirataz isn’t related? Hard to say of course.

I really hope you can get some answers. ((Hugs))
 
JL and Chip said:
Hi Elizabeth—
I’m sorry no one has responded. It’s not that no one cares … more likely no one has any concrete experience or suggestions.

I’ve read and re-read your posts a few times. I don’t have any first-hand experience (that I’m aware of anyway) with serotonin syndrome in cats. But I will offer a few thoughts.

First, a few questions …
- has anything at all changed recently in your home? Any chemicals sprayed for bugs, new essential oil diffusers, medications spilled, flea/tick medicine applied, anything whatsoever?
- has Jonah had any injections (other than Lantus) or supplements recently? Solensia perhaps? Vaccines? SubQ fluids (what type, how much/often)? Is he on any other medications or supplements?
- is Jonah indoor only?
- has anything changed with his food? Does he hunt and eat bugs or prey?
- are you certain that he can see? Are his pupils constantly dilated?
- how much mirataz were you using? How much ondansetron and how frequently?
- when he clocked those lower BG numbers on the Libre, I see you re-tested with a human meter. Did you test again before an hour passed to ensure he didn’t go even lower in the interim?

And just a thought … given that you felt the Mirataz was warranted daily rather than every few days, I wonder if something was already brewing and he was about to go “off the rails”anyway. Maybe the Mirataz isn’t related? Hard to say of course.

I really hope you can get some answers. ((Hugs))
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Thanks for responding. Given that the vets arw offering nothing, I really do feel as if I'm twisting in the wind.

I've gone over and over the things you mention. He is indoor only and has nothing to hunt. I am super anal about chemicals of all kinds and anything even remotely dangerous is on a top shelf in a closet that is always kept closed. I dont use flea/tick meds since he is indoors. No recent vax or other meds. We pulled the budesonide 2 months ago and now he is off everything else. And now really not eating, as Mirataz is what was making that happen.

Pupils are prerry dilated, but reactive, and he CAN see. ER ascertained that and I can tell. He runs into things but looks my way if I wave a hand.

Mirataz transdermal was 1.5" of ointment. Not sure how that works out in mg, as could find nothing about that on package or package insert. It is the standard dose. Ondansetron 2 mg 1-2x a day as needed.

Re: testing. Once I ascertained that the low number on Libre was not as low on the BG meter, I just kept checking the Libre. And it went up, not down.

Going to regular vet today, for all the good that will do us. 😪 He is now often collapsing and urinating. Last night I had to crate him with bed and LB because he would not settle on bed and I couldn't just let him stagger around the house. Having to syringe feed all meals, as the appetite stimulant part of the Mirataz from last week has completely worn off.
 
And he routinely gets lactated ringers, 100 mL, with B12 added. Usually a few times a week. Seems to stave off pancreatitis and when he was full-blown diabetic, if kept him from drinking obsessively and then vomiting up the water. ER vet told me to increase to daily just in case it would help clear the Mirataz.
 
What does Jonah weigh?

I have a tube of Mirataz here somewhere … I was thinking there was a ruler on the box. 1.5” was far more than I was advised to give, but my cat was on the smaller side. I’ve never been a big fan of mirtazapine in any form. We used cyproheptadine as an appetite stimulant back in the day and I still prefer it.

As for your insulin dose … I don’t give dosing advice generally. But it sounds like you’re pretty close to (as I call it) “Hail Mary to the End Zone” territory. Given there’s no history of DKA, I don’t think it would hurt to reduce the dose. You can look at it as switching to the SLGS method and he’s already dropped below 90 and earned a deduction in that case.

I’m very concerned about Jonah, especially what you described overnight. I don’t know what else to offer. If it *is* serotonin syndrome and you’re losing the battle, maybe you and the vet can put your heads together and see if there are any other “Hail Mary” treatments. I’m not familiar with cyoroheptadine in these circumstances, but if I’m losing the battle anyway, I might revisit the idea.

@Suzanne and Darcy Do you have any experience with this?
 
Found this on reddit. Could this be a weird reaction to Lantus??? This all started right after I raised dose to 2.5. And this is pretty much exactly what Im experiencing.

https://www.reddit.com/r/FelineDiabetes/s/JAUHSTb37p

TEXT BELOW

[Quote)my cat is struggling after starting lantus

(I've never made a post on Reddit so apologies if this comes out funky.)

My cat, Willow (15 years old), got diagnosed with diabetes on September 12th. She was at the vet for her annual exam- routine bloodwork came back to show her BG was 373, as well as glucose in her urine. No ketones. She had lost a little bit of weight when they weighed her, but it wasn't anything I noticed prior. She showed some increase thirst which was the only symptom I had noticed.

Like most of us, I started doing heavy amounts of research. My cat is my world and I obsessed about all of the information out there. I found so much solace on here. My vet was pretty general in his instructions and I'm so grateful that I found this thread full of amazing information and suggestions.

I immediately switched to low-carb. She was on Instinct grain-free salmon dry food before. She's a very picky dry food girly, so I went with the Dr. Elsey's brand. I also got her fancy feast pate. She doesn't love it, and has never been a cat to eat a large (enough) amount of wet food at once, but she will eat some twice/day. She loves Applaws but it isn't a complete meal for them. I give small amounts of the Dr. Elsey's throughout the day. She was a free-feeder before.

I got the ReliOn monitor and we've been doing so great with the BG readings. I test before every shot and we've already performed 3 curves at home. She handles the ear prick, as well as the insulin injections, like an absolute champ.

After her diagnosis, I switched her food and didn't start insulin until \~1 week later so I could see what the diet change did to her numbers. It brought her down by about 100. So she was consistently in the mid-upper 200s with the diet change and no insulin.

I'm struggling because-

The very first night I administered her Lantus glargine, she had a very strange reaction. She was disoriented and kind of wobbly. Very "off." We all know our cats so well and I knew instantly something was weird. I initially suspected a hypo event, so I checked her BG and it had gone from 270 to 212. She wasn't hypo in the numbers. I monitored her the rest of the night.

In the morning, I called my vet and described the reaction to insulin. They told me to check her BG that night and if she was under 300, don't administer insulin, and then do a curve the following day (no insulin). She might be extra sensitive to the medicine so we would go slow.

I did that- sent in the numbers- her BG was still high, so they recommended I start at 1U once/day in the morning for 1 week. After that, do another curve.

We did that, sent in the numbers, was instructed to start 1U 2x/day as she was still high, a couple times her number went much higher (\~400) than any number before starting insulin. We did 1U 2x/day for 10 days. And then I did another curve. These were the numbers. BTW we do 8am/8pm shot times.

10/14

pre-shot 7:53am 343

shot 8am

11am 244

3pm 275

530pm 273

pre-shot 7:55pm 297

shot 8pm

11pm 221

I emailed the vet the curve results the following day. I hadn't heard back yet, and then on 10/16, about 3.5 hours after her morning insulin, Willow was sleeping next to me on the couch, jumped down to go to her water bowl, collapsed and had a seizure. It was AWFUL. It lasted about 15 seconds. Again, I immediately thought maybe she was hypo, I ran and grabbed honey and rubbed it along her gums. Right after that, once she had stopped shaking and was upright again, I checked her BG- it was 286. Not hypo at all.

I called the vet, and luckily they could see her right away, with a different veterinarian. After an examination, another BG check at the vet, and a blood pressure test, they had no idea why the seizure had occurred. My vet mentioned the Somogyi effect but didn't seem too concerned and said that in her 24 years of practicing, she only had 1 cat go Somogyi. They thought maybe the seizure was a one-off. We went home and she seemed to improve throughout the day but I monitored her very closely.

The next day, my regular vet emailed me back- saying her numbers are still high so let's start 1.5U 2x/day. Do that for one week, and another curve. We increased the dose starting the evening of 10/17, so only 5 days ago.

With the dose increase, she seemed to be doing okay for awhile, numbers getting into the lower 200s. Last night, however, after her evening shot, she seemed SO uncomfortable/restless. Like, laying down for 5 seconds and then immediately switching spots or sides. She had a funny walk again- kind of drunk. She was 305 pre-shot just before 8pm, immediately started acting weird, at 9:22 she was at 243, and at 10:43 she was at 228. Again, not hypo.

This is a lot of information and maybe not necessary, but I'm wondering if anyone else has experience with a cat reacting badly to Lantus in particular? I feel like ever since we started insulin, she has declined and seems so much more uncomfortable. I've asked the vet multiple times if they've ever experienced this, or have any other concerns about other things going on. Why did she have a seizure? Why does she have hypo symptoms with hyperglycemic numbers? I'm at a loss at this point and am terrified every time I have to dose her. Could it be as simple as switching brands of insulin?

Overall, her demeanor is low. Her coat has also gotten incredibly dry since starting insulin. I'm so worried about her and can barely eat or sleep.[/quote]
 
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What would happen if I just pulled him off the Lantus? Given the time release aspect, that would be the only way I can see to determine if it is the culprit. Any dangers to doing that?
 
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I wouldn’t stop insulin completely. Clearly Jonah is diabetic and you risk other possible complications from untreated diabetes. However, you could always switch to Prozinc insulin. I believe the Reddit post you found is FDMB member @Kate & Willow … and I believe Willow did much better after moving to Prozinc.

Here’s a post from the old FDMB board that’s worth a read:
? - Need help/advice on cat having unusual response to Lantus | Feline Diabetes Message Board - FDMB

I read some of your earlier posts and, given Jonah’s history of sensitivity to medications and how the current problems seemed somewhat concurrent with giving Mirataz daily, it does seem plausible that that’s the culprit. But it’s an easy change to go with Prozinc. Just know that Prozinc is a U-40 insulin (rather than U-100) so you’ll need to either get U-40 syringes or use a conversion chart to use your current U-100 syringes. No big deal—we can help you with that. And because Prozinc is a pet insulin, you can usually get it from your vet (most human pharmacies don’t carry it).
 
I’m really sorry to hear about what is going on with Jonah! How terrifying!

Cyproheptadine should have been given if they really thought he had Seratonin Syndrome. I’m very surprised the vets did not know that Cyproheptadine is used to counteract Seratonin Syndrome. If this was all it is though and they believe it was caused by Mirtazapine (pills or Mirataz?) it should have worn off — maybe the vets were hoping it would just wear off and that was the approach they were taking.

Mirataz can certainly affect cats negatively if they are overdosed (and by overdosed I mean too much for any individual cat — some cats have a very low tolerance for Mirataz.) I never give my cats the full 1.5 inch strip of Mirataz (having had a bad reaction to doing that in one cat several years ago.) I give half or less than half a strip every other day — although I watch their behavior and adjust accordingly.) Currently I am having far better appetite stimulation with Cyproheptadine in one of my sick cats than we were getting with the Mirataz (which was causing extreme restlessness even at the half dose and not much appetite stimulation.)

There could be something else going on here that is neurological in nature and it sounds like he needs to be seen by some veterinarians who have more capability to diagnose what is going on with Jonah.

If you have a Nova Max Plus meter, have you been testing him for ketones? I would check it regardless of hos BG numbers. Have they run bloodwork on Jonah? If so, can you share that with is?
 
Elizabeth said:
What would happen if I just pulled him off the Lantus? Given the time release aspect, that would be the only way I can see to determine if it is the culprit. Any dangers to doing that?
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Based on yesterday’s NovaMax Plus BG reading, I would reduce him back down to 2.25 units - just because of the strange symptoms right now. And I helped @Kate & Willow with the ProZinc transition/dosing.
 
Suzanne and Darcy said:
I’m really sorry to hear about what is going on with Jonah! How terrifying!

Cyproheptadine should have been given if they really thought he had Seratonin Syndrome. I’m very surprised the vets did not know that Cyproheptadine is used to counteract Seratonin Syndrome. If this was all it is though and they believe it was caused by Mirtazapine (pills or Mirataz?) it should have worn off — maybe the vets were hoping it would just wear off and that was the approach they were taking.

Mirataz can certainly affect cats negatively if they are overdosed (and by overdosed I mean too much for any individual cat — some cats have a very low tolerance for Mirataz.) I never give my cats the full 1.5 inch strip of Mirataz (having had a bad reaction to doing that in one cat several years ago.) I give half or less than half a strip every other day — although I watch their behavior and adjust accordingly.) Currently I am having far better appetite stimulation with Cyproheptadine in one of my sick cats than we were getting with the Mirataz (which was causing extreme restlessness even at the half dose and not much appetite stimulation.)

There could be something else going on here that is neurological in nature and it sounds like he needs to be seen by some veterinarians who have more capability to diagnose what is going on with Jonah.

If you have a Nova Max Plus meter, have you been testing him for ketones? I would check it regardless of hos BG numbers. Have they run bloodwork on Jonah? If so, can you share that with is?
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As mentioned above, I'm getting 0.1-0.3 for ketones.

How can I post the labwork? It was unremarkable, BTW.
 
Labwork can be added into the labs tab of your spreadsheet (just make sure the reference ranges listed match your lab.) Or you can copy and paste a photo of it into your thread (making sure to conceal personally identifying information like your home address or phone number.)
 
Elizabeth said:
So I'm concerned that, because of the depot effect, just lowering the dose will take too long to work.
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I do not think it would be beneficial for Jonah to completely stop insulin. If you feel the need to drain his depot a little more quickly then you could skip the next shot and resume at the lower 2.25 dose at the following shot. How is he behaving today?

For anyone reading along: this suggestion is strictly for Johan because of the unexplained symptoms that he is currently having. It doesn’t apply to any other cat.
 
What are you feeding him? I see he went from 53 to 113 today and that is quite a jump.

What is his normal diet and how often (and at what points in the cycle are you feeding him?) Are you having any difficulty getting him to eat the mini meals that he should be eating during the early portion of his cycles?
 
If you feel strongly about stopping Lantus, then I’d pick up a bottle of Prozinc at the vet today. As Suzanne said, she can help you with the transition and dosing.
 
Suzanne and Darcy said:
What are you feeding him? I see he went from 53 to 113 today and that is quite a jump.

What is his normal diet and how often (and at what points in the cycle are you feeding him?) Are you having any difficulty getting him to eat the mini meals that he should be eating during the early portion of his cycles?
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I'm feeding him anything he will eat. He is more likely to step in the bowl than eat from it. Syringe-fed Friskies (higher carb) this AM due to low numbers. He should be getting raw but hasn't eaten it since this started. So compromised with Fancy Feast pate.
 
UPDATE.

Vet put in Prozinc order to their online pharmacy. It will ship. In the meantime, I can either skip one Lantus dose and then restart at lower dose (2.25?? 2.0??), or stop it entirely. Need to find out one way or another if Lantus is the culprit here or not.
 
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I'm glad you are getting Prozinc instead of Vetsulin. The latter doesn't last long in cats, and drops hard and fast.
Elizabeth said:
How can I post the labwork? It was unremarkable, BTW.
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There is a Labs tab on the spreadsheet. You have to manually enter. But I find it very useful to see trends and have since starting using Labs tabs for the non diabetics too.
Elizabeth said:
Ondansetron 2 mg 1-2x a day as needed.
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Ondansetron can be given more frequently if needed, up to 4 times per day. It doesn't last long in the (normal) cat.
 
I’m wondering why the vets felt there were risks with cyproheptadine and what they are. I’ve used it further over 27 years as an appetite stimulant as the side effects are so much less than with mirtazapine. I did try mirataz a couple years ago with one of my cats but it didn’t work. I know that cyproheptadine is the antidote for setatonin syndrome and wonder why the vet was against giving it. It’s my understanding it works pretty quickly if mirt caused that. I hope you had a good response to Prozinc.
 
Max@tif+chai&mocha2 said:
I’m wondering why the vets felt there were risks with cyproheptadine and what they are. I’ve used it further over 27 years as an appetite stimulant as the side effects are so much less than with mirtazapine. I did try mirataz a couple years ago with one of my cats but it didn’t work. I know that cyproheptadine is the antidote for setatonin syndrome and wonder why the vet was against giving it. It’s my understanding it works pretty quickly if mirt caused that. I hope you had a good response to Prozinc.
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Haven't started it yet.

The risks were that it can cause the same side effects as what he was experiencing, especially given his history with weird drug reactions. That said, I now have a script for it for appetite stimulation. Too scared to add more drugs right now though.
 
If he were my cat, I would not keep skipping shots. He went pink last night with no shot and today I see he’s already in the 300s again, which also carries bad effects of its own — unless you are seeing a complete turnaround in him since stopping insulin.

When will the ProZinc arrive?
 
Elizabeth said:
Haven't started it yet.

The risks were that it can cause the same side effects as what he was experiencing, especially given his history with weird drug reactions. That said, I now have a script for it for appetite stimulation. Too scared to add more drugs right now though.
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If you do try it just give a sliver, like 1/16 of a 4 mg. That is all Max needed and he was a big boy. You can always increase if not enough. I hope things are improving.
 
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