Hello. I am a respiratory therapist and have been watching the wonders of Chantix since it was developed. I have seen wonderful results in many patients. However, my husband could not take it. He became very mean and I took him off. Shortly there after, even though I was told this was not a side effect of Chantix, reports started coming out about this very issue related to Chantix. My point is, who knows? I would not think that Chantix would affect your thyroid, but everyone is different. Are you still taking Chantix? I am assuming not. ALso, I feel compelled to mention that I too had the symptoms you had, except for the trouble breathing, and my vitamin D level was extremely deficient. You may want to get that checked. Wishing you the best.
What is your TSH? Is that .443 a Free T4 test level?