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Dyes and Fillers used in Synthroid and Compounded Levothyroxine

Wondering if anyone else has experienced allergic reaction or sensitivities to 134 mcg (blue) Synthroid, and if anyone has switched to Compounded Levothyroxine with Avicel as the filler and had a reaction to that filler. Also wondering if Compounded Levothyroxine would be as effective in managing hypothyroid symptoms as Synthroid, as after my total thyroidectomy in 2006 they started me on generic levothyroxine and it did not help, but the brand name Synthroid did help to improve my TSH levels.
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649848 tn?1534633700
Have you definitely been determined to be allergic to dyes and fillers in Synthroid?   How long have you been taking Synthroid and what dose are you taking?  

We have had some members who have had reactions to dyes/fillers in medication.  You can try the 50 mcg pills, which are white (no dye).  If you're taking 100 mcg total dose, you could take 2-50 mcg tablets to make your dose, etc.   Synthroid has acacia in it, which some people have had issues with.  Changing to another brand, with something else might be helpful.

The brand that most people do well with is Levoxyl.  I've been on that for years since neither generic Levothyroxine and Synthroid worked for me.   Another good one is Tirosint, which is a gelcap and contains only glycerine, water, Levothyroxine and gelatin.  Tirosint tends to be the most expensive, but the manufacturer has programs for those who qualify.  

Is TSH the only thyroid related blood test that's being performed regularly?  What about Free T4 and Free T3?  Those are the actual thyroid hormones.  TSH is merely an indicator of thyroid hormone status and should never be used, alone, to determine dosage or type of medication required.  

All of that said, I don't recall anyone taking compounded Levothyroxine only.  Compounded thyroid medication, typically, contains, both T4 (Levothyroxine) and T3, which is the actual hormone used by individual cells, whereas T4 (Levo) must be converted to T3 - the usable hormone.
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Avatar universal
Hi, this is Soaplvr4evr answering Barb135. I have used Synthroid since 2006 (almost 19 years) due to my thyroids being removed for papillary thyroid cancer. Synthroid has only T4 in it, by the way. I need to stay hypothyroid all my life according to my doctor. I never had a problem with itchiness all over but mostly in my face, scalp, and ears. I do also have environmental allergies to some trees of which Acacia is high on the list. I never knew Acacia is in Synthroid. Now that I am older (65) I need to be careful not to take too high a dosage to prevent heart problems. I just recently started having itchiness just 22 minutes after Synthroid 137mcg (blue one), so my doctor switched me to compounded levothyroxine which has avicel in it (methylcellulose). I started the compounded one three days ago, but also am itchy on face, so I will call my doctor to switch the prescription to a compound pharmacy that's in-network with my insurance (only one such pharmacy is and it's in New Jersey), and they can use other fillers such as rice flour or tapioca starch for highly allergic people. If I get itchy from that too, then it probably is that I slowly developed an allergy to the levothyroxine.  I will then try levoxyl which I understand is throxine (not levothyroxine??). Anyways, I will start off with the other compound pharmacy (with only T4 along with either tapioca powder, rice flour or potato starch which all three are natural fillers. Avicel and Loxoral are both synthetic fillers the compound pharmacy said they also put in levothyroxine capsules, according to whatever my doctor writes on the prescription. Thanks for your quickly replying to my post before!
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Your doctor is incorrect in telling you that you need to stay "hypothyroid" for the rest of your life.   Because you have no thyroid gland, you will need to take medication for the rest of your life, but you should not be hypothyroid, which means you don't have enough thyroid hormones.

Yes, we all need to be careful not to get too much medication, but it's important that we get "enough", since too little thyroid hormones is just as dangerous for the heart as too much.

I'm aware that Synthroid is a T4, only medication.  I took it for a couple of years after I went hypothyroid and it didn't work for me, so I had to switch.  I tried Tirosint, which worked very well, but became too expensive.  The difference in the various medications is the fillers/binders and dyes.  I'm sure you're aware that each dosage is a different color, so a person could be allergic (or react) to one dosage and not another one.  The typical way to find out if fillers/binders/dyes are causing the problem is to switch to the 50 mcg tablets that are white and have no dye.  If that helps, you would know it's the dye causing the problem.

Inactive ingredients in Synthroid include the following:
    Confectioner's sugar (contains corn starch)
    Lactose monohydrate.
    Magnesium stearate.
    Various color additives.

It's also incorrect that Levoxyl contains "thyroxine".  It contains levothyroxine, just as Synthroid does; it simply contains different fillers/binders that most people tolerate easily.  Levothyroxine is the synthetic version of  thyroxine, which is produced by the body.  Levothyroxine is identical to thyroxine.

You could always try a desiccated type of hormones.  They're produced from pig thyroid, such as Armour.  It contains, both T4 and T3.  Although pigs produce more T3 than humans, many people do very well on desiccated hormones.   I took them for a while but insurance didn't cover them, so again, they because quite expensive for me.

I hope you do well on the new compounded medication.

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