Synthroid causing you acne?

I've been on Synthroid for 17 years. I take 200mcgs daily. I always get big painful red bumps on my chin. I've just chalked it up to hormones but I'm now 32 years old. I began research and found some people complaining that Synthroid is causing their acne. Anyone experience this? If so, how do you treat it? I haven't found anything that works. I just bought Tea Tree Oil today. Boy does it stink!