Is Cellulose the real problem in desiccated thyroid meds for many?

Screen Shot 2015-08-05 at 12.53.55 PM(This blog post was updated in 2015. Enjoy!)

When Forest Labs reformulated Armour desiccated thyroid in early 2009, they stated they increased the filler Microcrystalline Cellulose, and decreased the Sucrose (sugar). And all of sudden, the tablets became impossible to do sublingually–a method so many of us loved and which seemed to give even more of a punch.

And we were left wondering in 2009 why they would change a particular quality (being able to do the tablets sublingually) that thyroid patients praised so heavily?  Positive opinion among patients for Forest Labs back then slipped several notches. (Forest Labs was bought out by Actavis in 2014)

But the real cuckoo’s nest for many thyroid patients still on Armour in 2009, who knew firsthand the life-changing benefits of natural desiccated thyroid, was a maddening return of serious hypo symptoms on the 2009 Armour with its increase in cellulose, and subsequent new stress on their adrenals, sooner…or later! You can read several horror stories in the comments of the post below, or go here.

So patients turned to other alternatives, which at the time was Naturethroid and Westhroid by RLC Labs.

So what has been the common thread in the most problematic desiccated thyroid products?

It has always been CELLULOSE, a plant fiber, and more commonly known by the trade name Avicel. And what does fiber do in your stomach? Inhibits absorption. Armour’s cellulose was raised, and bamm…problems.  Compounded desiccated thyroid, with cellulose as a filler, has been problematic for many patients with a return of hypo symptoms, especially if it was Methyl Cellulose, a larger particle size product. But some have even had problems with compounded containing Microcrystalline Cellulose, the smaller cellular product. And a certain body of patients even had problems with Naturethroid back then before it became scarce for awhile. And Naturethroid used cellulose as a filler.

Note: With all the complaints, Forest Labs did change something about Armour by mid–to-late 2010. Though it never returned to what it was before 2009, it did become a softer tablet and patients did better on it. But we certainly learned a big lesson about cellulose in our NDT pills..

Is this problem true with T3-only products?

Yes. Patients noted that generic T3 was far less effective than the brand name Cytomel (both Liothyronine Sodium)  And what filler is up to 70% in the generic T3?  CELLULOSE.  

What does literature say about the use of Cellulose as a filler in medications?

Plenty. Cellulose is from wood. Wood is fiber. And fiber in your gut affects absorption. From we get this:

* Dietary fiber has been reported to lower the blood levels and effectiveness of tricyclic antidepressant medications…Reduced dietary fiber intake increased the blood levels and improved symptoms in these patients.

* While fiber supplements may help to regulate blood sugar levels, they may also interfere with the absorption of anti-diabetic medications….Therefore, fiber supplements should not be taken at the same time as these medications.

* Taking soluble fiber such as psyllium with carbamazepine (Tegretol), a medication used to treat seizure disorders, may decrease the absorption and effectiveness of carbamazepine.

* Fiber in the form of pectin (from fruit) and oat bran reportedly reduces the body’s ability to absorb cholesterol-lowering medications known as “statins,”… and could lead to decreased effectiveness of these medications.

* Fiber supplements may reduce the body’s ability to absorb digoxin (Lanoxin), a medication used to regulate heart function.

* Clinical reports suggest that psyllium or other soluble fibers may lower lithium levels in the blood, reducing the effectiveness of this medication.

* In one clinical study, the fiber supplement guar gum reduced blood levels of penicillin.

Fast forward to the present

Granted, many thyroid patients soar on about every brand or kind of desiccated thyroid as long as they raise it high enough, plus have discovered and corrected potential low iron and/or high or low cortisol. i.e. if you have had problems with NDT, your answer is here.

If you are using a compounded desiccated thyroid medication, it’s strongly recommended to request powdered acidophiles, also spelled acidophilus, as your filler.  One gal states her compounding pharmacy uses powdered Ginger (but beware of too much Ginger if you have Mitral Valve Prolapse. It can cause palps if you take too much–my experience).  Others might use powdered Vitamin C.  See what other fillers your compounder can offer.

Another possibility is Cellulase, an enzyme which helps the splitting and breakdown of cellulose, and which was proposed to me by Naturopathic doctor Stephanie Buist. It’s found on most supplement websites.

You can also study the ingredients of different brands, of which there are now some which have no cellulose!


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* Become an informed thyroid patient!

69 Responses to “Is Cellulose the real problem in desiccated thyroid meds for many?”

  1. Chelsea

    I just purchased a 30 day supply of compounded medication at a hefty price. It is made with cellulose, is there any way I can counteract that when I take it, at least until I can get the next batch without it?

  2. Brian Haviland

    Generally fillers should be inert and not interact with the medication. As your article indicates cellulose may not be inert in that sense. At an LDN group it’s suggested that people not use acidophilus for a similar reason. Hypo sucrose seems to be the safest choice. Why not to use acidophilus………

  3. Lynn

    I am not on Facebook but google pages I like and I just found out that Cytomel now has gluten in it. An appeal has been posted on Change.Org to Pfizer to remove it. Apparently this change took place 1.5 years ago. I take 25mcg Cytomel twice a day (can’t convert T4). Now I am in search of what to do now. Have you heard about this and if so, do you have any suggestions to those of us who take Cytomel? I wish I could just get off thyroid meds altogether, it just disgusts me what these companies do, what the government did to our access to Cynomel, etc. I would LOVE to be prescription drug free, and this is the only prescription I need so if I could stop using it I would. I remember Dr. Shames used to have a product but was never sure it would work for me, and then there was the Nutri-Med products. I just can’t seem to remember whether they were reviewed well. I use to take Cynomel years ago when I had a RT3 problem and signed up for some of the Yahoo boards to learn all about that, but that was years ago. I found out that Cynomel changed too and had to stop at that time and finally went to the expensive Cytomel. Now I’m starting ALL OVER AGAIN!?!?!?!! What a PAIN. Thanks in advance for any information you might have.

    • Janie Bowthorpe

      The gluten may be in the inactive ingredient excipient within Cytomel which is labeled “starch”. But that starch can be either corn, potato, tapioca, or wheat derived.

  4. Lynn

    So you are saying one batch could be wheat and irritate me, and the next batch could be potato and not be a problem? That seems like such a gamble for my poor tummy.

  5. Helen Hancock

    I had a real problem recently with a compounded time release t3/t4 medication that had methyl cellulose a filler. After taking it strictly as prescribed for a month my TSH. Free T3 and Free T4 results came back with a TSH of 11.5, previously all my TSH results are usually very low and my FT3 and FT4 came back lower than the low end of the range. Clearly, I derived no benefit whatsoever from the medication. I had the potency of the drugs tested and except for the T#3 being a bit low, pharmacist’s quote, the drug was fine as per the prescription. I can only think it must have been the fault of the methyl cellulose and its effect on my body’s ability to absorb it. I have since gone back to Nature Throid at a slightly increased dose and I feel so much better.


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