Would test thyroid antibodies and ferritin. However the itching and rash will also need dermatology follow-up - this may be a primary skin problem and not a thyroid issue. The other thing to consider would be an ANA to screen for other auto-immune issues. Also take a multivitamin, lutein, biotin, zinc and b-complex to support hair/nail health. With poor night vision - check vitamin A level -- if this is low and you are on a normal diet then expore for malabsorption.
Hi splank. I used to have "normal" labs, too, yet I had all of symptoms you mentioned (except the night vision problem)! It turned out definitely to be my thyroid. What kept going wrong for me is that docs were only testing my TSH and T4, and if they had checked my free T3, they would have seen it low in the range, which was a huge clue that I was hypo!! And I was!! And as Dr. Mark mentioned, you might want to check out your Ferritin, which for some reason, was low in me----and I've noticed it low in MANY hypo folks. And that causes the same symptoms as low thyroid. And by the way, if and when you do ever figure out that you are hypo, docs will tend to put you on T4-only meds--like Synthroid and Levoxyl. And those of us who were on those, and switched to natural dessicated thyroid (Armour is a common name), found the latter to work FAR better, since it gives us exactly what our own thyroid gives us, and not just T4. Just a thought..
I'm a almost 50 year old female, and I experienced all of those symptoms (plus more) before I was diagnosed hypo. Night blindness and vision disorder has been listed as a hypo symptom, as have all the others. Although I experienced different skin disorder from you, skin disorder is not uncommon in hypo. In fact a PubMed abstract says it can be the first indicator of a endocrine problem even before labs go out of range.
What i think might be helpful for you is to see the actual thyroid hormone levels, which would be Free T4 and Free T3. Hopefully the endo you're planning to see will run those. I've seen many folks who were "functionally hypo" (normal TSH, normal Free T4, low Free T3. And of course it appears antibodies can cause hypo problems even when everything is in range.
I sure hope you find someone to help you resolve these hypo symptoms. Hypothyroidism, when not treated in a timely manner, can really wreck your health permanently. Best of luck to you - I've been where you are and I hope you obtain resolution of your symptoms.