I have been using rice milk for the last few months. I've known for years that I'm lactose intolerant. So I've been drinking Lactaid. Stomach would get really, really bloated, like a basketball in there. A few months ago I gave up Lactaid and got rice and almond milk. Both good, I just stuck with the rice milk(we're rice farmers, so supporting our products!). My stomach is not nearly as bloated as the Lactaid era, but I don't too much watch every ingredient. My stomach was bloating on Synthroid, and saw one of its ingredients was lactose, so that may explain the problem with Synthroid and my extra stomach bloating.
I switched from Synthroid to Unithroid, and the "basketball" thingy in the stomach went away. I looked up Unithroid, and it did not have lactose in its ingredients. Good luck, and maybe in the long run, finding the right med will help some of your weird allergy symptoms go to rest forever!
Maybe you could get a compounded T4/T3 combo without the lactose fillers????
I have a lactose intolerance & used lactaid for years until my stomach just wouldn't tolerate it any longer. Accidently, I noticed that Nestle's quick chocolate powder seemed to relieve the bloated etc somewhat when I drank milk. So now I just have a cup of hot chocolate & can tolerate 2 cups of milk a day.
BTW I have my diuretic (HCTZ) compounded or make up with cornstarch by a compound pharmacist. He used cornstarch as a filler & then puts it in a capsule which I dump out into my pumpkin pudding. Wish all my meds were that easy to take. I have difficult swallowing so my meds have to be liquid or have the ability to disolve in water. Fam