A brief educational explainer by McCall McPherson describing three common reasons patients respond poorly or have adverse reactions to desiccated thyroid products (Armour, NP Thyroid): (1) improper immediate switch from levothyroxine causing an effective overdose due to differing T4 half-lives and desiccated-thyroid pharmacokinetics; (2) underdosing because many clinicians lack training in dosing desiccated thyroid; and (3) once-daily dosing of short-acting T3-containing preparations causing peak/trough symptoms—recommendation to split doses (morning + late afternoon).
Chapters
You tried armour or NP thyroid and it didn't work or you had a bad reaction to it. I've gotten a lot of questions about why this is and I want to answer it for you. So basically there's a few ways that this can go wrong. Number one, the most common issue I see is someone trying to transition from Levothyroxine or Synthroid to armor. And what their doctor does in order to do this is they have them take, stop taking their Levo or Synthroid on let's say a Monday for example, and start armor on a Monday. What's the problem with that? A lot. So the Half life of T4 Levosynthroid is 10 days, meaning half of it in most people still in their system 10 days after they stop taking it. So armor is largely short acting, meaning the day that you take it, T3 is in your system, the active hormone in it, and T4 is more short acting than it is in Levo. So effectively, if you stop Levo one day and you start the quote, equivalent dose of armor the same day, you've effectively doubled your dose in one day, which is really uncomfortable. Those people experience symptoms of jitteriness, palpitations, anxiety, feeling uncomfortable, edgy. So obviously that's one problem. The second super common problem is underdosing. So clinicians, doctors, we are not trained how to appropriately use desiccated thyroid. So every. We are not trained a how to use it and we are trained to be very afraid of it and we are trained not to use it. So in fact we are terrified of it, don't know how to adequately dose it, and also have no like formal education in how to appropriately do so. So what ends up happening is people get massively underdosed. Is that a problem inherently with armor or np? No, it's a problem that hey, of course you don't feel well if you're not getting the right dose of medication. Third is once a day dosing. So those meds, NP armor are short acting. The T3 in them, the part that makes largely the difference in people's quality of life, peaks and troughs in about six to eight hours. So all of my patients are dosed in the morning and in the late afternoon. Otherwise people crash and burn in the afternoon. Their TSH has a hard time reducing. If you only are on once a day dosing doses of desiccated thyroid and the long acting symptoms that you need coverage for, hormones, metabolism, hair, skin, cognition, all those things don't work as well when you're on once a day dosing. So, like, I. I've said it before, I'll say it again. It's not as simple as being on the right dose of medication. You need the right dose at the right time and the right medication. So I hope that offers a little bit of clarity. I know that was a long one, so hope you made it through. Save this for later or tag a friend that maybe needs to hear this info.
