Exemestane/Thyroid issues?

Hello, I haven’t posted on here for ages and it’s all so new! I have a question regarding Exemestane and possible Thyroid interactions. I was taking Arimidex for 18 months until my consultant who was also a Thyroid specialist thought it was messing with my Thyroid meds and took me off Arimidex indefinitely back in May 2015. Somewhere I got lost in the system and was told he retired and they forgot about me until I contacted my breast nurse in the summer. She sorted me out with a new consultant who I see in Oct and discussed with the weekly breast team that I must start back on Hormone Therapy and gave me Exemestane which I started 2 months ago. I wondering if anyone also has an under active Thyroid and has it been affected by taking any Hormone Therapy meds? Cheers, Michele ?

Hi Michele, 

Welcome to the Forum again but I am sorry you find yourself here. 

I am sure that users will be along to share their experiences soon but in the meantime you can always call ourhelpline on 0808 800 6000 who will be able to talk through any questions you have on thyroid and hormone therapy. The opening hours are below. 

Monday-Friday, 9am-5pm
Late opening Wednesday 9am-7pm
Saturday, 9am-1pm

Best wishes, 


Very interested in your post as my pre-op medical picked up an underactive thyroid.  I wasn’t even aware of any symptoms.  I started on Anastrozole last summer and Levothyroxine (50mcg) a short time later.  Although it mentions possible interaction problems in the leaflet, my GP has never said anything to me. However, the first year blood test I’ve just had has led to my dose being increased to 100 micrograms.  I take my thyroxine first thing in the morning before breakfast and my anastrozole last thing at night to keep them as far apart as possible.  If you find out anything of interest, I’d love to hear about it. I do get bad hot flushes but as both tablets have these as side effects, I’m not sure which to blame (or both?).