SERUM TSH LEVEL 5.8 (0.2 - 4.2 MIU/L) Most people don't feel well until their TSH level is 1.0 or a little lower. You need your levothyroxine dose increasing and retest in 6 weeks time and then another dose increase until your feel well or reach TSH 1.0 or thereabouts.
ANTI TPO ANTIBODY 376 (<34 IU/ML) ANTI TG ANTIBODY 258.3 (<115 IU/ML) These results show you have autoimmune thryoid condition otherwise known as Hashimotos. Read Thyroid UK website information on Hashimotos to find out more.
SERUM FREE T4 LEVEL 13.4 (12.0 - 22.0 PMOL/L) FT4 level is very low confirming you are undermedicated.
SERUM FREE T3 LEVEL 3.2 (3.1 - 6.8 PMOL/L) FT3 level is very low, you need it in the top third of the range. This confirms you are undermedicated.
Besides the advice Nanaedake has given, some of your symptoms are indicative of low nutrient levels. Have you had vitamins and minerals tested:
Vit D
B12
Folate
Ferritin
Iron panel
Full blood count
If so please post results and say if you are supplementing, with what and the dose.
Some information about Hashi's:
You can help reduce antibodies by adopting a strict gluten free diet which has helped many members, gluten contains gliadin which is a protein thought to trigger antibody attacks. You don't have to be Coeliac for a gluten free diet to help reduce antibodies. Also, supplementing with selenium L-selenomethionine 200mcg daily and keeping TSH suppressed can reduce antibodies.
Do you have test results from when on higher dose too?
Your antibodies are high this is Hashimoto's, (also known as autoimmune thyroid disease). About 90% of hypothyroidism in UK is due to Hashimoto's.
Hashimoto's very often affects the gut, leading to low stomach acid, low vitamin levels and leaky gut. About 5% are coeliac, but over 80% of us find gluten free diet helps significantly. Either due to direct gluten intolerance (no test available) or due to leaky gut and gluten causing molecular mimicry (see Amy Myers link)
But don't be surprised that GP or endo never mention gut, gluten or low vitamins. Hashimoto's is very poorly understood
Changing to a strictly gluten free diet may help reduce symptoms.
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