Synthyroid: Some thoughts and queries.

[Geetal]

I recently reread the instructions with my Synthyroid as I had begun to have difficulty swallowing the tablets and found that the instructions had changed in 2017. Does anyone have an old copy to see if any of my following queries applied then as well or are new?

1)Fillers:confectioners sugar.I am not diabetic but I wonder how many readers who are hadnt realised that was a filler. Similarly Lactose monohydrate for those who are milk intolerant. Each tablet contains 62.87mglactose and 62.87 mg sucrose. This information is in section 6. In section 2 towards the end it says that the medicine contains sucrose and lactose and may harm people who are sensitive /intolerant to lactose and/or sucrose. Surely these comments should be at the top of the instructions in bold.

2) In section 2 regarding Blood Tests it says that some medicines may affect the results of blood tests.It does not list them. Does anyone know which medicines affect the results?

In Section2 regarding food it says certain foods such as Soya,cotton seeds and walnuts and dietry fibres and calcium may reduce absorption of levothyroxine.

Do any readers know of any published papers that justify that stement?.

In particular this is the first time that I have read that there is a problem with walnuts and cottonseeds?

3)In Section 3 it says that although the tablet has a partial scoreline ,it is not recommended to halve the Synthyroid tablet. If this is the case why do they not make Synthyroid in 25mcg sizes as everyone I know who takes it has at some time or another been told to either cut the 50mcg tablet in half or take it on alternate days which to my mind is far worse.

[MaisieGray]

" If this is the case why do they not make Synthyroid in 25mcg sizes"

Synthroid tablets start at 25 mcg, see here rxabbvie.com/pdf/synthroid.pdf and here synthroidpro.com/dosing/

For drug interactions with Levo generally, see here bnf.nice.org.uk/interaction... and referring to synthroid specifically see here at section 7 rxabbvie.com/pdf/synthroid.pdf

[Geetal in reply to MaisieGray]

Many thanks. You have a set of instructions very different to mine and for a later date. Yours are from USA and mine from Israel but both are produced from AbbieVie inc. It seems like you can get 25mcg in USA although not in Israel.

I must go out now so Ill read the rest of your response later . Once again many thanks.

[Geetal in reply to MaisieGray]

Very many thanks. Its really incredible not only does USA have a much wider range of dose sizes but the instructions attached go to 19 pages whereas in Israel ours are only 9 pages in English. I asked our Doctor why we could not have 25mcg as they were obviously being produced and he said as Synthyroid has a low profit margin we have to take what we are given and cant make them supply exactly what we want as we are a small market compared to the US.

Regarding walnuts the links you sent me had a contact us button(we have nothing like that on the Israeli version) and so I have requested details of any published papers they have demonstrating that walnuts reduce the absorption of levothyroxine. If I get any response Ill let you know,

[helvella in reply to Geetal]

Synthroid in the USA has a huge profit margin.

In many countries, levothyroxine is cheap, or very cheap. In the UK, 28 tablets are around one pound.

Synthroid is expensive in the USA because they have managed to persuade people that it is so much better than any other product.

No idea of cost in Israel.

Is Synthroid supplied to Israel manufactured by Abbvie? Or by Mylan in Canada? (A lot of the Synthroid supplied outside the USA is manufactured by Mylan.)

[Geetal in reply to helvella]

manufacturer abbvie inc usa, registration holder abbot medical laboratories ltd tel aviv.

I am seeing my doctor again next Sunday afternoon soI shall print out your response and take it to show him.

[helvella in reply to Geetal]

For clarity - we do NOT get Synthroid in the UK. We have four makes - all are cheap. We get 25, 50 and 100 microgram tablets - but one make also has 12.5 and 75 microgram tablets. Teva. An Israeli company...

[Geetal in reply to helvella]

Ironic isnt it. Our healthFund does not provide Teva as an option.I shall take this reply from youwith as well on Sunday.

[SlowDragon Administrator]

If you are having trouble swallowing, perhaps you are not correctly medicated and need blood levels retested

How much Levothyroxine are you currently taking?

Have you got recent blood test results and ranges to add?

For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also extremely important to test vitamin D, folate, ferritin and B12

Low vitamin levels are extremely common, especially if Thyroid antibodies are raised

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and fasting. Last Levothyroxine dose should be 24 hours prior to test, (taking delayed dose immediately after blood draw). This gives highest TSH, lowest FT4 and most consistent results.

[Geetal in reply to SlowDragon]

Many thanks. I got my latest results yesterday morning and have arranged that I will speak to my doctor as soon as possible,but I suspect that will now be after the easter school holidays. I wrote the email during the night when I couldnt sleep so probably ordered my queries poorly. What I really need/want is any published papers relating to foods which as I have hypothyroid I shouldnt eat. Hence the email which referred to walnuts which I hadnt heard about being not suitable for hypothyroid people before.

[Geetal in reply to SlowDragon]

Many thanks. I have now seen my Doctor and reduced my Synthyroid dose. What is TG as all other tests you refer to are taken,but I have not heard of TG.

Please see my reply to Maisie about Walnuts. It will be interesting to see if I get a response from Abbots.

[SlowDragon Administrator in reply to Geetal]

Perhaps you might consider putting a new post up with your latest blood test results

For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also extremely important to test vitamin D, folate, ferritin and B12

There are two thyroid antibodies to test for Hashimoto's

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

healthline.com/health/antit...

Low vitamin levels are extremely common, especially if Thyroid antibodies are raised

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and fasting. Last Levothyroxine dose should be 24 hours prior to test, (taking delayed dose immediately after blood draw). This gives highest TSH, lowest FT4 and most consistent results.

[helvella]

A paper that jimh111 posted a few days ago has a specific test of bran (with water) and shows a substantial effect.

thyroid.org/wp-content/uplo...

Since I became involved with thyroid matters, the number of substances which impact absorption has rocketed.

Walnuts:

ncbi.nlm.nih.gov/pubmed/418...

Cottonseed (gossypol):

ncbi.nlm.nih.gov/pubmed/233...

This issue of the scoreline seems to be common. It is suggested that scorelines are there for identification and to make it easier to break a tablet to ease swallowing. I think that is justification after the event - used to be there for splitting but they want to run away from that fact.

As for swallowing - UK products same something like put into water and stir well. That allows the tablets to disperse and you can just drink the medicine. (I suggest pouring some more water into the empty glass and swallowing that to try to ensure nothing is left behind.)

[vocalEK in reply to helvella]

Any idea what type of bran? In my cupboard I have wheat bran and oat bran. I understand that there are many other types.

[helvella in reply to vocalEK]

I think it was ordinary wheat bran - nothing special. And it reduced absorption of levothyroxine substantially.

[Geetal in reply to helvella]

I have just gone onto the link regarding walnuts and it refers to coffee with no reference to walnuts. Can you please check the link .

[helvella in reply to Geetal]

Just checked, the link to the paper goes here:

Endocrinology. 1970 Mar;86(3):696-700.

Goitrogenic effect of walnut and its action on thyroxine excretion.

Linazasoro JM, Sanchez-Martin JA, Jimenez-Diaz C.

PMID: 4189852

DOI: 10.1210/endo-86-3-696

ncbi.nlm.nih.gov/pubmed/418...

Clicking on the DOI link takes me here:

Goitrogenic Effect of Walnut and Its Action on Thyroxine Excretion

JOSE M. LINAZASORO JOSE A. SANCHEZ-MARTIN CARLOS JIMENEZ-DIAZ

Endocrinology, Volume 86, Issue 3, 1 March 1970, Pages 696–700, doi.org/10.1210/endo-86-3-696

Published: 01 March 1970

The results reported here show that walnuts (Juglans regia) have a clear goitrogenic effect in rats, associated with a higher thyroid radioiodine uptake than that of the controls; an increase of PB131I and BE131I plasma levels with simultaneous normal PB127I content; normal intrathyroidal 131I distribution; normal BMR values; and a statistically significant increase in the elimination of thyroxine by the fecal route. It is suggested that the above findings could be interpreted as being secondary to the increased excretion of thyroxine, which, by depleting the body stores of thyroid hormone, subsequently induces an increased secretion of TSH in order to maintain an adequate production of thyroxine by the thyroid gland to compensate for the thyroxine loss. It is possible that the increased fecal thyroxine excretion may be due to some specific effect of the walnut diet on intestinal absorption. (Endocrinology86: 696, 1970)

academic.oup.com/endo/artic...

[Geetal in reply to helvella]

Sorry I should have looked below your walnut comment instead of above.

[jamesal0]

chew and swallow with a glass of water

[vocalEK in reply to jamesal0]

How big are your tablets? I'm in the U.S. and my Synthroid tablets have always been very tiny when compared with other medications I take--about the size of the tip of my little fingernail. In comparison, an aspirin would cover my entire little fingernail.