Underactive thyroid & vit c: Hi , just after some... - Thyroid UK

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Underactive thyroid & vit c

foggybrain31 profile image
17 Replies

Hi , just after some advice on taking vit c with levothyroxine 75 mg . I am currently feeling wiped out all the time but my results are within range just at 4 so doc will not increase dosage. I heard that vitamin c may help .

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foggybrain31
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Clutter profile image
Clutter

Foggy, vitC is good for health and wellbeing and should be taken 2 hours away from Levothyroxine but it's more thyroxine that you need. TSH should be just above or below 1.0 for people on Levothyroxine although there are some that need it lower or suppressed to feel well. Scroll down to Treatment Options to read Dr. A. Toft's statement in Pulse Magazine.

thyroiduk.org.uk/tuk/about_...

Email louise.warvill@thyroiduk.org.uk for a copy of the article to show your GP.

It's worth asking your GP to test ferritin, vitamin D, B12 and folate too. They're often low/deficient in hypothyroid patients and this can cause fatigue, musculoskeltal pain and low mood.

gabkad profile image
gabkad in reply to Clutter

Clutter, yesterday I read on the Harvard website for doctors that vitamin C taken with thyroxine can improve absorption. It is recommended for patients with persistently high TSH even when doses are increased.

(It was a troubleshoot page to figure out when patients levels don't go up when prescribed dose is increased. Interesting it also mentioned how some patients only absorb about 40% of dose and therefore require 200 to 300 mcg per day.)

Clutter profile image
Clutter in reply to gabkad

That's interesting, Gabkad. I know vitC increases absorption of iron. Did they say how much vitC was needed?

gabkad profile image
gabkad in reply to Clutter

If they did, I can't remember. Sheesh.

It was an interesting thing though: If they suspect that either a patient is non-compliant (as in, 'sometimes I forget to take my pills') or if they suspect that there is poor absorption, they give the patient 1,000 mcg T4 and measure excretion in the urine. And yes, indeed, there are people who despite doing it all the right way, just don't absorb the stuff well. So I thought that was really interesting given that some people here only feel good on really high doses.

Oh and, get this: if there are compliance issues, they recommend the patient take the total T4 required for a whole week in one dose. Like, let's say someone's daily dose is supposed to be 125 mcg, just take 875 mcg once per week.

NO I was not that far into the 'spirit' world, Clutter. ;) For real!

This was on the Harvard website and I found it by googling thyroxine absorption problems............... It's for doctors. (I guess the NHS crew don't read this stuff, eh.)

gabkad profile image
gabkad in reply to Clutter

Okay, Clutter I'm partly full of sh*t. It's from Medscape:

medscape.com/viewarticle/70...

gabkad profile image
gabkad in reply to gabkad

reported frequently.

(5) Investigate for malabsorption. Unfortunately, levothyroxine is not fully absorbed after oral ingestion. On average, only about 70–80% of the available tablet dose is absorbed in euthyroid individuals.[5] Interindividual variability in the efficiency of gastrointestinal (GI) absorption is fairly large and this variability accounts for most of the range of requirement seen between compliant patients after adjustment for body size. Malabsorption syndromes increase the requirement for levothyroxine by further reducing the fraction of the ingested dose that is absorbed. Patients with short bowel from prior small bowel bypass or resection commonly require higher than expected T4 doses. If the patient has frequent, voluminous stools, a malabsorption disorder may be evident and measurements of stool fat can confirm this diagnosis. However, thyroxine malabsorption has been reported as the initial finding in patients with otherwise asymptomatic malabsorptive syndromes, especially coeliac disease.[6] I screen patients that get this far along the diagnostic pathway with measurement of tissue transglutaminase antibodies and, if positive, send them for GI evaluation, usually including small bowel biopsy and stool fat measurements. Correction of the malabsorption will normalize or at least improve thyroxine absorption in these patients. Helicobacter pylori infection, especially when accompanied by atrophic gastritis and achlorhydria, has been reported to impair thyroxine absorption by up to 37% in patients with multinodular goitre. Antibiotic treatment of the H. pylori infection was also demonstrated to improve absorption and reduce thyroxine requirement in those patients.[7]

gabkad profile image
gabkad in reply to gabkad

(6) Consider increased turnover or excretion. A number of drugs or clinical conditions may increase the turnover or excretion of thyroid hormone and thereby increase considerably the requirement in individuals that are thyroid hormone dependent. Some examples are phenytoin, carbamazapine and rifampin. Several of the new kinase inhibitors, such as imatinib and sunitinib, that are entering the clinic for various malignancies appear to influence thyroxine requirements in this manner and this may be a class effect, although reports to date are few.[8–10] In addition, patients with nephrotic syndrome who excrete large quantities of albumin may have increased thyroxine requirements due to binding of T4 to the excreted albumin.[11,12] Women experience increased thyroxine requirements during normal pregnancy, that may reach as much as 50% at its peak.[13]

gabkad profile image
gabkad in reply to gabkad

(7) Perform a thyroxine absorption test. A clinical test to estimate thyroxine absorption has been proposed that may have utility in patients who have unexpectedly high T4 requirements. This test involves administration of a single large dose of levothyroxine, usually in the range of 1000 μg, then monitoring T4 levels in blood over time.[4] Although I have occasionally performed this test, I do not find it to be generally helpful unless it demonstrates completely 'normal’ results, thereby supporting patient noncompliance. Unfortunately, there is no well-established standard to which individual patient results can be compared, especially one done in hypothyroid patients with normal absorption. In the few circumstances when I have asked a patient to perform the test, the results indicate that the patient does absorb thyroxine when exposed to a large dose, but leaves me wondering if it is a normal amount or not, because of the lack of adequate normal standards. Furthermore, severe hypothyroidism itself may impair absorption, presumably due to oedema of the small bowel mucosa and this cannot be quantified by the test. Thus, I have not found that this test helps me very much in the decision-making process in individual patients

gabkad profile image
gabkad in reply to gabkad

And now for the piece de resistance: (Literally)

The patient described at the beginning of this article was very convincing in her description of faithfully ingesting her thyroxine tablets and had for several months been doing so in the absence of other, potentially interfering medications or supplements after advice from her primary care provider. Although she still described symptoms of hypothyroidism, I could not elicit symptoms suggestive of malabsorption. Her thyroid function tests confirmed inadequately replaced primary hypothyroidism in that her TSH remained elevated at 29·4 mIU/l and her free and total thyroxine levels were at the lower end of the normal range, this after ingesting 300 μg of thyroxine for approximately 8 weeks. The screens for malabsorption and coeliac disease (transglutaminase antibodies and stool fat measurement) were negative and urinalysis was normal. I elected to increase her levothyroxine dose to 400 μg daily and 6 weeks later her TSH was below normal (0·2 mIU/l) and free thyroxine was elevated (25·7 pmol/l). We reduced the thyroxine dose to 350 μg daily and after 8 weeks found that her TSH and free thyroxine levels had returned to normal. Her fatigue and constipation also improved and she stated that she felt much better than before.

I have seen a small number of patients (unreported) that appear to have selective malabsorption of thyroxine. These patients clearly absorb levothyroxine poorly but do not have evidence of generalized malabsorption or of coeliac disease and respond well to increasing the levothyroxine to levels well above those considered usual, in the range of 400–600 μg per day. At present I am not aware of a physiological explanation for these findings but I suspect one will be forthcoming with further investigation into thyroxine transport and absorption. The patient described above may be a representative.

gabkad profile image
gabkad in reply to gabkad

This guy is much more informative than Weetman that's for sure.

Comment at the end of the article:

Dr. william jubiz

May 1, 2013

We are completing a study in which we demonstrate correction of malabsorption of levothyroxine with vitamin C. There is a similar study from Argentina but we have more complete data.

gabkad profile image
gabkad in reply to gabkad

500 mg of vitamin C.

ncbi.nlm.nih.gov/pubmed/246...

BACKGROUND:

Malabsorption of l-T4 is a major clinical problem. Changes in gastric pH caused by several medical illnesses are associated with difficulties in the control of patients with hypothyroidism receiving the hormone. Means to correct these alterations would be of clinical value.

OBJECTIVES:

Our objective was to study the effect of vitamin C on the absorption of l-T4 in patients with hypothyroidism and gastritis.

DESIGN:

Thirty-one patients with hypothyroidism, 28 females age 47.5 ± 13.5 (mean ± SD) years and 3 males age 55.7 ± 11.2 years ingested the dose of l-T4 in 120 mL water containing or not containing 500 mg vitamin C in a solution of pH 2.9 ± 0.1 (mean ± SD). Serum concentrations of free T4 and TSH were measured at the end of 3 periods of 2 months each, 2 controls and 1 vitamin C. Serum total T3 was measured in 16 of the patients, before and at the end of the vitamin C period. Serum TSH and free T4 and T3 were measured by a solid-phase, enzyme-labeled chemiluminescent competitive immunoassay All patients had gastrointestinal pathology and were not in good control when taking l-T4 before the study, and 23 had autoimmune thyroiditis or idiopathic hypothyroidism. The median l-T4 dose was 100 μg with an interquartile range of 50 μg. The protocol was reviewed and approved by our institution's ethics committee. Patients were asked to sign a written consent to participate in the study.

RESULTS:

Serum concentrations of TSH, free T4, and T3 improved while on vitamin C. Serum TSH decreased in all patients (control, 11.1 [10.5] μIU/mL, median [interquartile range]), vitamin C 4.2 (3.7) μIU/mL, P = .0001), and it was normalized in 17 patients (54.8%). The average decrease was 69.2%. Serum T4 was higher with vitamin C in 30 of the 31 patients (control, 1.1 [0.3] ng/dL; vitamin C, 1.3 [0.3] ng/dL; P < .0001), and serum T3 increased as well in all 16 patients in whom it was measured (control, 60.5 [16.5] ng/dL; vitamin C, 70 [21] ng/dL; P < .005).

CONCLUSIONS:

In patients with hypothyroidism and gastrointestinal pathology, vitamin C improves the abnormalities in serum free T4, T3, and TSH concentrations. This approach is helpful in the management of these patients.

Clutter profile image
Clutter in reply to gabkad

Lol, Gabkad, take vitC with vodka for brain fog :-D Good article, thanks for that. I've read of patients with suspected compliance being forced to take a week's worth of T4 in front of the doctor. Interesting to see the woman's dose boosted to 400mcg to increase absorption and then being reduced to 350mcg after gut 'learned' to absorb. Nice to see that patients were believed and the doctor went on to investigate malabsorption. High dose vitC has been found useful in chemo too.

gabkad profile image
gabkad in reply to Clutter

Damn, forgot the vitamin C. Taking it now....

I don't think the patient's gut 'learned' anything. I think the doctor learned. And judging by what he's written he learns A LOT! I think there are a number of people around here who don't absorb well.

I know I do based on how trippy it was to take a total of 25 mcg T3 in one day. Altered sense of reality. I felt like I was looking at the world from deep inside my skull.

Clutter profile image
Clutter in reply to gabkad

Gabkad, I think so too given the amount of people who have low ferritin/iron, vitD and B12. I wonder if taking high dose vitC improves absorption even when taken apart from Levothyroxine?

gabkad profile image
gabkad in reply to Clutter

No idea Clutter. Vitamin C improves the integrity of tissues which is why, let's say, deficiency results in bleeding gums. I'm sure any tissues that have high cell turnover (like the gut lining) are affected in the same way.

Supposedly we need very little. But that's the same as the B12 range. Optimal is different. Probably different with vitamin C as well.

Clarabelle77 profile image
Clarabelle77 in reply to Clutter

ncbi.nlm.nih.gov/m/pubmed/2...

Lots of reputable studies now showing that 500mcg-1000mcg vit c taken with thyroxine not only lowers TSH and raises T4 but also raises serum T3, which is crucial for those not absorbing or converting properly. Basically, DO take vit C with your thyroxine 👍👍👍

sandysm profile image
sandysm in reply to gabkad

This is true that taking vitamin with thyroxin helps a lot, there was a study done on it and the people in the study had to lower there medication because of the vitamin c which is great news youtube has a lot of videos about the great affects off this vitamin hope this helped xx

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