Just as a word of caution, ashwagandha may not be for you if you are pre-disposed to hyperthyroidism or have significant allergies. I've been supplementing with ashwagandha in the past couple months, and although I have never been diagnosed with hyperthyroidism, my dad has it. I have several plant allergies as well...ragweed, trees, stuff like that.
Recently I've been struggling with dry eyes, blurry vision, difficulty sleeping, somewhat racing thoughts, and an overall feeling of inflammation and slightly tender throat. I missed my ashwagandha supplement yesterday and slept great last night, no tenderness in my throat, eyes are clearer, I'm calmer, my vision seems better, and I'm not as drowsy. I don't seem as "strung out" or like a bundle of nerves.
Come to find out interactions amongst hyperthyroidism, allergies, and ashwagandha can cause all of my unusual symptoms. The change was enough after only one day that I actually took the time to write this post. I'm going to abstain to ensure it's not some placebo effect but it's looking like ashwagandha isn't for me. Maybe this post will help someone else.