I was diagnosed with underacrive thyroid and put on 50mg of Levothyroxine. My test results were
Serum TSH Level(XaELV)3.72 miu/L [0.38-5.35]
Classed as normal. I have problems withy weight even though I am careful of what and when I eat and also am quite active. How do I know if I'm on the correct dose as I had to ask to be put on to medication fir my thyroid.
Was just TSH tested?
You need your FT4 & FT3 tested to know what your thyroid levels are.
The aim if taking levo is to have a TSH around 1 the lower part of range and FT4 should be in top third of range.
If you convert well your FT3 the active thyroid hormone, should be at least half way through range.
Levo wont work well if you don’t have good nutrients. Folate,ferritin, B12 and vitamin D. In range is acceptable to doctors you need optimal.
As your TSH is 3.72 you are under medicated should have a dose increase of 25mcg per day you then need to retest after 6 weeks.
Were thyroid antibodies previously antibodies? TPO & TG antibodies.
Welcome to the forum
How long have you been on 50mcg levothyroxine
Which brand of levothyroxine are you currently taking
50mcg is only a standard starter dose of levothyroxine
Bloods should be retested 6-8 weeks after each dose change or brand change in levothyroxine
Always test as early as possible in morning before eating or drinking anything other than water and last dose levothyroxine 24 hours before test
Just testing TSH is completely inadequate
Has GP run any other tests
For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested.
Very important to test vitamin D, folate, ferritin and B12
Low vitamin levels are extremely common, especially with autoimmune thyroid disease (Hashimoto’s or Ord’s thyroiditis)
Low vitamin levels common as we get older too
Anaesthetic can also cause B12 to drop
Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)
But with TSH over 2 you should be prescribed next 25mcg increase in levothyroxine
TSH should be under 2 as an absolute maximum when on levothyroxine
gponline.com/endocrinology-...
Replacement therapy with levothyroxine should be initiated in all patients to achieve a TSH level of 0.5-2.0pmol/L.
Aim is to bring a TSH under 2.5
UK guidance suggests aiming for a TSH of 0.5–2.5
gp-update.co.uk/SM4/Mutable...
NHS England Liothyronine guidelines July 2019 clearly state on page 13 that TSH should be between 0.4-1.5 when OPTIMALLY treated with just Levothyroxine
Note that it says test should be in morning BEFORE taking levothyroxine
Also to test vitamin D, folate, B12 and ferritin
sps.nhs.uk/wp-content/uploa...
I had to keep asking my doctor to check my Thyroid as they didn't seem bothered about my levels and I feel like they just put me on this dose as a way of saying you're Ok now. Feel very frustrated and fobbed off by them
Extremely common problem….hence over 120,000 members, vast majority from UK
Guidelines on dose Levothyroxine by weight is quite clear
Dose Levothyroxine is increased slowly upwards in 25mcg steps until TSH is around 1
Typical eventual dose is around 1.6mcg per kilo of your weight
Request 25mcg dose increase in Levothyroxine
Plus vitamin testing and thyroid antibodies if not already tested
If on HRT likely to need higher dose Levothyroxine eventually
guidelines on dose levothyroxine by weight
Even if we frequently don’t start on full replacement dose, most people need to increase levothyroxine dose slowly upwards in 25mcg steps (retesting 6-8 weeks after each increase) until eventually on, or near full replacement dose
NICE guidelines on full replacement dose
nice.org.uk/guidance/ng145/...
1.3.6
Consider starting levothyroxine at a dosage of 1.6 micrograms per kilogram of body weight per day (rounded to the nearest 25 micrograms) for adults under 65 with primary hypothyroidism and no history of cardiovascular disease.
Also here
cks.nice.org.uk/topics/hypo...
gp-update.co.uk/Latest-Upda...
Traditionally we have tended to start patients on a low dose of levothyroxine and titrate it up over a period of months. RCT evidence suggests that for the majority of patients this is not necessary and may waste resources.
For patients aged >60y or with ischaemic heart disease, start levothyroxine at 25–50μg daily and titrate up every 3 to 6 weeks as tolerated.
For ALL other patients start at full replacement dose. For most this will equate to 1.6 μg/kg/day (approximately 100μg for a 60kg woman and 125μg for a 75kg man).
If you are starting treatment for subclinical hypothyroidism, this article advises starting at a dose close to the full treatment dose on the basis that it is difficult to assess symptom response unless a therapeutic dose has been trialled.
BMJ also clear on dose required
Which brand of levothyroxine are you currently taking
Many people find Levothyroxine brands are not interchangeable.
Many patients do NOT get on well with Teva brand of Levothyroxine.
Teva contains mannitol as a filler, which seems to be possible cause of problems.
Teva is the only brand that makes 75mcg tablet. So if avoiding Teva for 75mcg dose ask for 25mcg to add to 50mcg or just extra 50mcg tablets to cut in half
But for some people (usually if lactose intolerant, Teva is by far the best option)
Teva, or Aristo (100mcg only) are the only lactose free tablets
Most easily available (and often most easily tolerated) are Mercury Pharma or Accord
Mercury Pharma make 25mcg, 50mcg and 100mcg tablets
Accord is also boxed as Almus via Boots, and Northstar 50mcg and 100mcg via Lloyds ....but Accord doesn’t make 25mcg tablets
beware 25mcg Northstar is Teva
List of different brands available in U.K.
thyroiduk.org/if-you-are-hy...
Once you find a brand that suits you, best to make sure to only get that one at each prescription.
Watch out for brand change when dose is increased or at repeat prescription.
New guidelines for GP if you find it difficult/impossible to change brands
gov.uk/drug-safety-update/l...
If a patient reports persistent symptoms when switching between different levothyroxine tablet formulations, consider consistently prescribing a specific product known to be well tolerated by the patient.
academic.oup.com/jcem/artic...
Physicians should: 1) alert patients that preparations may be switched at the pharmacy; 2) encourage patients to ask to remain on the same preparation at every pharmacy refill; and 3) make sure patients understand the need to have their TSH retested and the potential for dosing readjusted every time their LT4 preparation is switched (18).
Levothyroxine is an extremely fussy hormone and should always be taken on an empty stomach and then nothing apart from water for at least an hour after
Many people take Levothyroxine soon after waking, but it may be more convenient and perhaps more effective taken at bedtime
verywellhealth.com/best-tim...
No other medication or supplements at same as Levothyroxine, leave at least 2 hour gap.
Some like iron, calcium, magnesium, HRT, omeprazole or vitamin D should be four hours away
(Time gap doesn't apply to Vitamin D mouth spray)
If you normally take levothyroxine at bedtime/in night ...adjust timings as follows prior to blood test
If testing Monday morning, delay Saturday evening dose levothyroxine until Sunday morning. Delay Sunday evening dose levothyroxine until after blood test on Monday morning. Take Monday evening dose levothyroxine as per normal
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