6 years and still in the dark

Are you being optimally treated for your thyroid? I had terrible rashes on my face until I was diagnosed and treated - and on a high enough dose!

I had rashes on my face and elsewhere when my nutrient levels were low. Getting thyroid hormone levels up high enough helped as well.

The fact that the rash disappeared when you had flu makes me think the problem is caused by an autoimmune condition of some kind. While your immune system was busy attacking the flu virus it couldn't attack your skin as well.

Rather than taking strong anti-histamines, have you considered going on a low histamine diet? Googling for "low histamine diet" could give you some ideas.

histamineintolerance.org.uk/

histamineintolerance.org.uk...

The foods to avoid eating (high histamine foods) are given on the second link.

Yes! That's what I've told a few GPs and they have just said that it was a coincidence that it went when I was poorly. Thanks for that I'll look up a low histamine diet

Are you on Levothyroxine? Do you have a Thyroid condition? If so do you have Hashimoto's (high antibodies) also called autoimmune thyroid disease

Sounds like rash could be gluten related, especially if you have Hashimoto's

If you have Hashimoto's then hidden food intolerances may be causing issues, most common by far is gluten. Changing to a strictly gluten free diet may help reduce symptoms and eventually start to lower antibodies. Very very many of us here find it really helps and can slowly lower antibodies, improving symptoms

thyroidpharmacist.com/artic...

thyroidpharmacist.com/artic...

amymyersmd.com/2017/02/3-im...

chriskresser.com/the-gluten...

Hashimoto's very often affects the gut, leading to low stomach acid, low vitamin levels and leaky gut.

Low vitamins that affect thyroid are vitamin D, folate, ferritin and B12. Important to test these. If they are too low they stop Thyroid hormones working. Have these been tested, if not ask that they are. Always get actual results and ranges.