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Antihistamines with low thyroid condition - OK or not?

I've recently started taking thyroid supplements for my hypothyroid condition.
I've been told that if you take antihistamines, it stops the thyroid tablets working properly. I am having a nightmare with hayfever - the pollen count seems to be breaking all records!
Is it true that I need to avoid antihistiamines? I'm getting a bit desperate.
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Avatar universal
You have to do your own homework and be your own advocate...keep it up!

T3 is much more potent and fast-acting than T4.  So, it can directly and quickly increase heartrate.  Most people split a dose of T3 in half, taking half in the morning with their levo and half later in the day, but, even at that, there are more peaks and valleys in FT3 levels than there would be from normal conversion.  

A long time ago, before I became my own advocate (when I knew nothing), I asked my PCP about adding in a little T3 to my meds.  At the time, I was taking 44 mcg of T4.  She agreed and suggested that we lower my T4 to 25 mcg and add in 25 mcg of T3.  Now, this was absurd.  T3 is about 4 times more potent than T4, so my overall dose would have increased tremendously.  Furthermore, taking T4 and T3 in a ratio of 1 to 1 is virtually unheard of (usually you take much more T4 than T3).  I didn't know a lot then, but I did know enough to protest.  We settled on 5 mcg of T3 although she protested that that was "a dose we give to babies".  She, obviously, did not understand that you don't use T3 like you use T4.  I only took the T3 for about a month because it didn't do a thing for me.  When I think back on that, I cringe...she could have killed me.with that much T3.  She never even told me to split the dose.
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Avatar universal
Thanks so much for all this advice goolarra.

Do you know what the issues are with T3 and arrhythmias?
I've had so many doctors who seem to know nothing beyond their own field of specialisation that i prefer to do my own homework to make sure nothing goes wrong!
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Avatar universal
A couple of good questions can really weed out endos pretty fast.

I'd first ask which thyroid tests they customarily order for their hypo patients.  You want to hear FT3, FT4 and TSH.  If anyone says TSH only, you can cross him off your list.  If they say FT4 and TSH, keep them in mind, but continue your search.  FT3 is very important, in fact it's the test that correlates best with symptoms.  However, it can be hard to find an endo who orders it regularly, but many will order it on request.  So, depending on the responses you're getting, you might not want to toss out the FT4/TSH guys just yet.

Another good question is which meds the doctor is open to...T4, synthetic T3/T4 combos, desiccated?  Ideally, you'd like to hear all three, but that rarely happens, even in the States since most doctors have their biases and in some countries desiccated isn't even available.  Also, any meds with T3 are usually contraindicated for anyone with an arrhythmia.

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Avatar universal
Based on what yo usaid, it sounds as if my lyme doc is taking the right approach to the heart issue. I'll watch out for any heart symptoms when I take my next dosage step up. So far it has been fine, actually improved over what I had before.

I didn't realise that diabetes thing was universal! Here in Sicily, it seems like half the population over 50 is diabetic, so finding an endo who even claims to be interested in anything other than diabetes is a challenge! But I have a friend who is an ENT specialist and he is healping me search. If you can suggest any questions I should ask I would be really grateful!

Barb,
I have been tested for heaps of antibodies,. Apart from the 3 thyroid ones, I've also had tests for Addisons disease and a whole bunch of other things - I can't remember what!
2 of my doctors (I have so many!) said with most auto iimmune illnesses you have to rely mainly on symptoms as there aren't specific tests, but they are confident I don't have any of the nasties like Lupus for example.
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649848 tn?1534633700
COMMUNITY LEADER
What antibodies have you been tested for?

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Avatar universal
How slowly you build the dose depends on your reaction to each increase.  Remember that it takes 4-6 weeks for the meds to build in your system and reach full potential in your blood.  It's always best to stay on a dose 4-6 weeks, re-test, re-evaluate symptoms and go from there.  I had to increase very slowly.  In fact, I couldn't always move to the next higher "standard" dose.  I split and combined a lot of different dose pills to get intermediate doses.  My rule of thumb was never to increase until I had completely gotten used to the previous dose.  If my tachycardia increased, I stayed put for a while.

My doctor started me on 88 mcg because she had no clue it would impact my WPW even though I had asked her that question directly.  A couple of weeks into the 88 mcg, my tachy had gone wild.  I backed off and backed off until I was on 25 mcg.  My tachy was still out of control, so i saw my EP, who put me on a beta blocker.  Luckily, HE knew what thyroid meds could do to me.  

"My lyme doc is managing the thyroid situation so far, though he wants me to get an endo too - but says I must make sure I find a really good one."  Your Lyme doctor sounds like a smart guy.  All endos are not equal.  Some only want to treat diabetes.  If your Lyme doctor doesn't have a referral for you, you might want to pre-interview endos over the phone before making an appointment to help weed out the bad ones.  We can suggest questions if you're interested in that.

I got lucky and found a great endo.  I don't even see my EP any more since my endo is comfortable prescribing the beta blocker I take.  Since my levels stabilized and I've been on a stable dose for several years now, my tachy has improved a lot, too.  In fact, i am coming up on two years next month without an episode.  I've had tachy since I was 7 or 8, so that's quite an accomplishment for me.  So, I don't think you need to see the EP unless your heart symptoms are exacerbated.  If you do see him, just be sure to update him on your thyroid meds.

Sufedrin can cause tachycardia and can cause it to last longer, so it’s best to avoid it.
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Avatar universal
Thanks for your replies.

Personally I think the Lyme disease caused the arrhythmia but I don't know for sure - the cardiologist said there is no way to prove or disprove that and she is putting her bets on it being a genetic/congenital thing. In most cases they never find out the cause. My arrhythmia is ventricular tachycardia (the one 2 football players recently died of in Italy and England).
I had a heart operation (catheter ablation) 4 years ago, which improved it drastically. I was basically at the point where it only sprang up when I had bad flu, or if my lyme was in a bad flare-up and causing a great deal of generalised inflammation.
The arrhythmia started coming back when my thyroid was extremely low but even on this tiny dose it has improved a lot, which to me confirms that it was struggling and acting up without enough thyroid.

How slowly/fast did you build up the dose?
What would you advise me to be careful of/ask the docs etc? Any warnings you can give me would be much appreciated.
My lyme doc is managing the thyroid situation so far, though he wants me to get an endo too - but says I must make sure I find a really good one.
Do you think I should go see the electrophysiologist about the thyroid/heart situation too?
With all my various conditions I have to consult so many different doctors so often, that I just get sick of it really. (I set myself the goal this year of having more hairdresser appointments than doctors' appointments, but so far I am failing dismally in this ambition!)

I had no idea I should not take sufedrin, what would that do to me?

Barb,
I've been tested for Hashimotos and definitely don't have that. (Thank goodness). I do have a high level of autoimmune antibodies and nobody can figure out what they are acting against (irritatingly), but it's definitely not my thyroid.

Have you had the radioactive iodine test? My Lyme doc said he thought that would be the best follow-up test on the nodules.

I am scared of anything to do with iodine, particularly wierd iodine, because another part of my back story is that, before the heart operation, I was given amioderone. It is a heart drug that contains heaps of iodine and gives lots of people hyper or hypo thyroid. It made my thyroid crash out to ridiculously low levels in a matter of days. The way to make your thyroid recover after that it to not take any thyroid... I had to wait 6 months for everything to go back to normal... but anyway I still have residues of this disgusting poison of a drug in me (I can tell because it stays in your skin and makes it go greyish blue in sunlight). I just wish I knew how to make my body excrete it.
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649848 tn?1534633700
COMMUNITY LEADER
Do you know if you have Hashimoto's Thyroiditis?  That's an autoimmune thyroid disease, in which the body sees the thyroid as foreign and produces antibodies to destroy it.

Thyroid nodules are very common in those of us with Hashimoto's.  They are usually nothing to worry about, unless they have distinctive characteristics. I have multiple nodules on my thyroid.

Antibody testing for Hashimoto's would be blood tests for Thyroid Peroxidase Antibodies (TPOab) and Thyroglobulin Antibodies (TGab).  You  have to be tested for both, because either one will confirm Hashimoto's.
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Avatar universal
Do you know the cause of your heart arrhythmia?  I only ask because I have WPW syndrome and a lifelong history of tachycardia.  Believe me, I found out the hard way how important it is to start low and build the dose slowly when you have a heart arrhythmia...unfortuately, my PCP was clueless about that.

You do know to avoid sufedrin, right?  As far as thyroid is concerned, correct, you should be able to take antihistamines once thyroid levels are properly adjusted for you.  However, I would check with my doctor if I were you to make sure they are compatible with your heart arrhythmia.  

Many of us have nodules.  If they're not large or suspicous looking, they're often just monitored for changes.  
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Avatar universal
Hi,
Thanks very much for replying.

I have hypothyroid caused by Lyme disease. That means I have low T3 and T4, but fairly low TSH as well (it's in range but near the bottom).

I am taking levothyroxine. I've only just started taking it (started 5 weeks ago) so I am only on 25 mg, definitely not at the dose I need but obviously I have to be patient to build up. (I have a lifelong history of heart arrhythmia so the level of thyroid needs to be handled extremely carefully).

So based on the info you found, it looks as if I should be able to take antihistamines once I am supplementing at the full level that I need?

I also have nodules in my thyroid gland. They showed up on ultrasound and I am still looking for a good endocrinologist to investigate that further. The lyme doc says nobody knows if lyme disease can cause those too, so they may be due to something else.
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Avatar universal
I found this with a quick google search:

"Some cold remedy medications are not recommended for thyroid patients. There should be no problem at all taking a decongestant or an antihistamine if thyroid levels are normal and in balance. This is true even though the package insert says it should be avoided by people with a thyroid disease. A patient whose thyroid levels are too high will be oversensitive to decongestants. The combination of too much thyroid hormone and decongestants might cause even more tremors, more nervousness, and more shakiness. They might make the heart beat faster. This will also happen if diet pills, a large amount of caffeine, or some asthma medications are taken while thyroid levels are too high. Once thyroid levels have been treated or adjusted, it should be much easier to tolerate all of these products.

On the other hand, if thyroid levels are too low, oversensitivity to antihistamines as well as sleeping pills and any other type of sedative will occur. They will all tend to make one even more sluggish and drowsy. So, be careful if thyroid levels are too low. Otherwise, if thyroid levels are normalized by treatment with thyroid hormone, these medications should be tolerated."

What do you mean when you say "thyroid supplements"?  Which thyroid condition do you have?
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Avatar universal
PLEASE?
Is there anyone who knows anything about this at all?
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