Hello there, Thank you for your question. The symptoms you have described can be side effects of Adderall or it could mean you are overdosed with levothyroxine. Adderall is not causing you thyroid to be more active. But palpitations are a side effect of Adderall. If the dose of levothyroxine you are taking is slightly more than what you require then also you may have these symptoms. The only way to tell is by getting a TSH test done. From its level we can judge if you are correctly dosed. Do discuss this side effect with your psychiatrist if your TSH value comes back normal. Your psychiatrist can reduce doses or stop the medication based on benefit risk balance. Hope this helps. Take care.