Has anyone noticed an increase in their horses cribbing after starting them on Thyro L ??
it wouldn’t surprise me, as that will metabolically rev up the horse, which can be stressful. Does he (still) have free choice stuff to eat?
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If my thyroid meds are high, I get anxious as all hell. It’s an AWFUL feeling. I’d totally crib if I could! I’d take a hard look at the dose and maybe dial it back a little?
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Yes, he always has Low Sugar Hay in front of him 24 seven whether it’s in the stall or outside in the arena… He’s a 17 year old thoroughbred of mine who started having some subclinical laminitis and tender feet a few months ago so we pulled him off grass switch to the ECIR recommended guidelines and emergency diet and his comfort level and his feet improved almost immediately… Bloodwork indicated, low thyroid, so vet had me start him on one scoop per day -it wasn’t long after that we noticed he did start cribbing more… However, he used to be on Purina outlast, which we stopped when he was having the sensitivity with his feet, and his blood work did show somewhat high insulin and glucose. Nothing terrible, but higher than you’d like to see… So a few changes being pulled off pasture stopping the Outlast and adding thyro L.
AC TH came back in the gray area of I guess being acceptable for the time of seasonal rise… However come January we plan on doing the TRH stim and retesting him because I just can’t imagine a thoroughbred truly being insulin resistant
Is he overweight though? IR in TBs is pretty uncommon, and when they are, they’re often “hard keepers”
What date was blood pulled for the ACTH test, and what number came back? Laminitis problems “a few months ago”, ie around the peak of the seasonal rise, would have me thinking PPID over IR
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The vet thought it may be a touch, overweight… However, for me him being a thoroughbred and a show Hunter, he looks like a perfect weight to me… No cresty neck or anything like that, but yes, this bloodwork was taken around September, so probably right in the height of seasonal rise… My suspicion is Cushing’s… We also tested for Lyme, which was negative
what was the result of the ACTH test? I don’t understand the Thyro-L for a not-overweight horse even if the number as a little high, before considering other causes with better management (like PPID)
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My cushings horse was also hypothyroid when we first ran the cushings test. The thyroid corrected itself after I started prascend.
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Ok …so I dug up his lab results which came in on 10/17/23 - Insulin 59, Glucose-all vet wrote was un exciting, Acth-70.7, Thyroid- 0.242, Leptin 13.78 , Lyme - negative…so since those results he was taken off grass/pasture and switched to arena turnout after about 2 wks stall rest , switched to tested low sugar grass hay, and added Insulin Wise and 1 scoop Thyro L(started at 1/2 scoop for 1 week then bumped up to 1 scoop ) , discontinued the Purina Outlast…ouchy tender feet improved very quickly …fast forward to now and I can see a hint of ribs and he is cribbing alot since those changes
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70 in October is equivocal. The TRH Stim test now would be a good idea. I still don’t understand the vet’s reasoning for the Thyro-L 
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Could it be the cribbing isn’t reflective of the addition of Thyro-L, but reflective of the management changes responsible for the symptom[s] Thyro-L is attempting to address?
I would wonder why the Thyro-L as well, unless vet is thinking the subclinical laminitis symptoms would benefit from reduced weight.
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The vet recommended the Thyro L due to the low thyroid level and also because she felt he was a bit overweight?? Anyhow I’m starting to wean and taper him off it …I will be rechecking insulin , glucose and acth with the stim sometime this month when they come back out for some others.
The vet said Thyro L because his thyroid level came back low and also because she felt it might help initiate some weight loss.
I also think taking him off pasture and stopping the Outlast could also be contributing
I get it that she said that, but the info you’ve provided don’t seem to warrant that as the first step. It’s not like he was obese. It’s just SO odd for that drug to be suggested in this situation
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Lots of vets still rx thyro l like this. Had a friend who’s vet put her THIN but cushingoid pony on it. She couldn’t figure out why she couldn’t get weight on him. Good vet, not a hack, just not up to date on metabolic stuff. It’s not uncommon.
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Yeah I agree …she doesn’t want me weaning him off it either until we recheck his blood work to see if insulin came down but I’m not listening 
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