One of the things that I keep reading is that the generic drugs aren’t as good as the name brands. That sounds very fishy to me since that’s not the case with any other drug but I figured it’s worth investigating. It looks like there’s indeed something fishy going on there: Research comparing the most popular brand-name drug with another brand-name and two generics was suppressed. The researchers found:
For all nine comparisons, there was no statistically significant difference between the four formulations, indicating that they were bioequivalent, even using a criterion for bioequivalence considerably more stringent than that employed by the FDA for other compounds. The authors concluded that the four generic and brand levothyroxine preparations studied were bioquivalent and interchangeable for most patients taking levothyroxine hormone.
The authors were forced to withdraw the article one day before the JAMA issues was supposed to go to print. Instead the opposite of their findings were published in a little known journal claiming that the brand-name was superior. Although it looks like it was published a year after these issues were raised. Note the small sample size of 22 patients, though. (Also read Public Citizens statement on the efforts of the brand-name manufacturer to keep control of the market).
While trying to find answers and a more reliable treatment, it’s almost inevitable that I come across websites peddling Armour Thyroid, a supposedly natural desiccated thyroid alternative to the synthetic medications that are prescribed. Public Citizen dared to advice against Armour Thyroid. The author of the article, self-proclaimed patient advocate Mary Shomon, then goes on to commit just about every logical fallacy there is while attempting to defend Armour Thyroid. She takes issue with Public Citizen’s reliance on the American Thyroid Association’s statement and then suggests rewriting it as: “There is no evidence in the form of published, peer-reviewed, double-blind studies that desiccated thyroid, a biological preparation, has any advantage over synthetic thyroxine.” Well, that would mean that there is no scientific evidence for desiccated thyroid. Anecdotal evidence doesn’t count, sorry Mary.
Most of Shomon’s arguments take the form of “there’s something wrong with the synthetic thyroid medicine, therefore the desiccated thyroid must be good.” Uhm, no. It could mean that both are bad. It definitely means that we need more research, some of which was suppressed as Shomon pointed out (though, unlike what she’s implying that research did not include desiccated thyroid; plus, as I pointed out above the JAMA did publish the article in 1997, six years before Shomon’s post). And one of her main arguments, that Synthroid isn’t properly FDA approved, was true until 2006: “Synthroid did not have FDA approval, but now all L-thyroxine preparations have FDA approval.” Shomon couldn’t have know that, of course, when she wrote the article in 2003…
Shomon also points to a study that found that “among patients taking thyroid medication, only 60% were within the normal range of TSH.” She writes that this fact “indicates that either vast numbers of doctors do not know how to properly prescribe levothyroxine, or it may not be as effective as its manufacturers and supporters claim.” First, again, that doesn’t mean that the “natural” alternative is any better because they, too, might be exaggerating their claims. And I would not be as quick to dismiss the improper prescription levels by doctors. Both hypothesis seem plausible to me. Though I’d start with checking on the skill of prescribing the right level of hormone replacement, especially given that many doctors are still using an outdated TSH range.
Why does Shomon think Armour Thyroid is still being used? The first reason is price. What a sorry reason! Homeopathic remedies are also pretty cheap but are worthless. Price does not say anything about the quality of something. The second reason is price again, this time hidden behind the claim that synthetic thyroid medication manufacturers are gouging consumers. But again something bad about another thing doesn’t make the alternative good! Third, T4 replacement might not be enough. There’s a study that shows this based on 33 patients, which is hardly conclusive. The authors of that study conclude:
In patients with hypothyroidism, partial substitution of triiodothyronine [T3] for thyroxine [T4] may improve mood and neuropsychological function; this finding suggests a specific effect of the triiodothyronine normally secreted by the thyroid gland.
This is not an endorsement of Armour Thyroid simply because that contains both T4 (thyroxine) and T3 (triiodothyronine). There might be other, better alternatives. Also, it seems to me that there might be something else going on: T3 is the active form of T4, the body converts T4 to T3. So, maybe there’s something going wrong with that conversion process that could be treated directly. In their subscription-only article on Armour Thyroid, Public Citizen points out that “Three randomized controlled studies published in late 2003 failed to confirm any benefit of combined T4 and T3 treatment compared to T4 given alone” (one on 46 patients, two on 40 patients, and three on 110 patients).
Why does Public Citizen think that Armour Thyroid is still in the top 200?
Why, after over 25 years of advice to the contrary, is Armour Thyroid in the top 200 most frequently prescribed drugs in the United States? One explanation appears to be that thyroid replacement therapy with natural thyroid appears to have become a niche market for unscrupulous complementary and alternative medicine (CAM) practitioners, some of whom are licensed MDs. Some of these CAM practitioners are also promoting natural thyroid hormone as a part of their weight loss programs. This is a dangerous practice, but it is not new.
Incidentally, Public Citizen does not advocate Synthroid, which is what Shomon seems to imply to discredit their whole argument against Armour Thyroid. They are advocating using synthetic levothyroxine in generic form.
I do agree with Mary Shomon on one thing:
The best thyroid drug for each patient is the drug that safely and effectively works the best for each patient. To suggest otherwise displays a lack of knowledge about the current state of thyroid treatment, and an utter disregard for the quality of life, future, health – and pocketbooks – of millions of Americans.
Well, it didn’t sound to me, though, that Shomon was objectively evaluating the available options. She was defending Armour Thyroid, not arguing for more nuanced treatment options, except in this last paragraph. What is need, in my opinion, are more independent studies, like the one that was suppressed, which compare the available options and figure out which work best. Clinging to an outdated medication is not the best option. Patient advocates who so blatantly dismiss the scientific method do not help us thyroid patients. They just add to our confusion.