Re: Synthyroid side effects
Synthroid and other levothyroxines are hormones, not physiology-changing drugs. The active ingredient is the same hormone your gland would be making if it could. Therefore, it's not logical to think one can be "allergic" to that hormone. The fillers, binders, and dyes used to manufacture the pills are another thing, though. Fortunately, not all brands use the same inert ingredients, so changing brands until you find one that works without allergic reactions should solve the problem. If it doesn't, you should conclude the reaction is due to something else.
I know how miserable that kind of itching can be. Here's hoping you figure it out soon.