liothyronine monitoring

[randomdoc1]

Excuse my ignorance. I had zero experience with this in residency and am in the process of trying to figure this out, doing some reading and thought I'd ask SDN too for some wise words. I monitored T3, T4, and TSH on a patient I inherited on this. Patient's got an unspecified anxiety disorder on top of the depressive disorder to begin with. But when you monitor, what exactly is your threshold for determining that the liothyronine dose is too high? I know what the typical dose is. The TSH came out about half the lower limit of normal and T3 is double the upper limit of normal. Patient's mildly tachy (100's-109) since starting the liothyronine, was moderately tachy (110's) when previous provider had her on over 50mcg a day. Reporting a lot of anxiety to me. I'm starting to err on the side of decreasing the liothyronine dose to 37.5mcg from 50mcg, maybe even going down to 25mcg. Other issue is also polypharmacy, liothyronine was patient's idea and in addition to the 6 psychotropics she is on and not wanting to engage in more intensive therapy, she requested another med be added. I'm also trying to gently broach that topic at some point but any thoughts on the liothyronine?

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[wolfvgang22]

Was this patient euthyroid before starting liothyronine? If so, in such a scenario I would probably taper the liothyronine down to at least to 25mcg and taper other medications starting with the one with the least usefulness/highest likelihood of side effects and monitor frequently in clinic. It will take some time for hormone levels to change, so no need to exsanguinate the patient with labs. I rarely place a patient that does not have hypothyroidism already on more than 25mcg of liothyronine. I usually start at 12.5mcg.

If this patient has hypothyroidism or other thyroid issues, and was not euthyroid to begin with I would enlist the assistance of IM, at least a phone call for guidance.
In fact, that is what what I recommend you should do in this case since we don't have the full picture.

 

[splik]

First is, what is the cytomel augmenting? The evidence does not support adding T3 to an SSRI/SNRI. STAR*D did not adequately answer this question and the results are quite difficult to interpret - and it really makes no sense what they did in this arm of STAR*D (where it was compared to SSRI+lithium which also makes no sense). The data mainly supports adding Li or cytomel to a TCA or MAOI. If not on one of those, I don't use it. I know some people use lower doses, but the data really supports the 25-50mg dose range. In this case, I would suggest going down to 25mcg and contacting PCP. Since the symptoms are presumably due to exogenous T3 then symptoms should clear when you decrease it, otherwise you might have to stop it entirely.

you didn't tell us what the FT4 was? I've treated several patients with this and they usually don't have problems (though I had one patient develop hallucinations on cytomel that abated when it was stopped). If she is experiencing signs of hyperthyroidism, the dose is way too high (the levels are less important, we treat the pt not the level). Also has she had an ECG?

 

[randomdoc1]

Yup, euthyroid at baseline. Actually, TSH was in the lower end of normal at baseline. Most of them less than 1 but still within normal range. FT4 I did is about half of the lower limit of normal. And yes, it is augmenting an SSRI. I'll definitely give PCP a heads up. Don't know if there is a recent EKG, my remote access unfortunately doesn't let me see it. But I probably should have thought of that when seeing the patient. At that time the only thing that crossed my mind was to do the monitoring labs for the liothyronine that was due anyways. Thanks for the input! I do feel a little more at ease about my initial thoughts and ideas and great idea with the PCP. At first I didn't think of contacting the PCP since I'm also presuming it's due to the T3 and signs and symptoms should resolve with backing down on the T3.

 

[splik]

you are right in that decreasing the dose should resolve sx but in this day and age we should be coordinating care. We don't have the ability to deal with all the patient's problems and provide the same high standard of care for both physical and mental health problems. In the unlikely case the patient had AFib from the cytomel and had an embolic stroke, you would be liable and found to breach your duty of care by not looping in the PCP about the cardiac symptoms of the pt's iatrogenic thyrotoxicosis.