Bleeding on Anastrozole...Why?

mrighter

I was prescribed anastrozole post-mastectomy. I'm age 56, confirmed to be post-menopausal. Ten days after I started anastrozole, I started bleeding - as if I had a period. Gyn did a D and C, removed a polyp, took a biopsy. It came back complex hyperplasia - no atypia. I resumed the anastrozole. Now, two months later, I have another heavy period. Upon return to my gyn, he recommends a hysterectomy. My concern is though...does the bleeding mean that the anastrozole isn't working? If it's supposed to shut down estrogen, why am I having this side effect normally caused by estrogen increase and decrease? No one can tell me why anastrozole causes bleeding in some women. Has anyone found a reasonable answer to this? Sure, I can get the uterus out, but is that getting rid of the symptom, and not addressing that fact that this medication is not effective?

fizzdon52

Hi I've just had the same problem on Femara/Letrozole so they have taken me off it for a couple of weeks and then I am going on something else. I was told is wasn't actually a period though, just random bleeding. I've also had blood pressure and heart problems. I have to have a pelvic ultrasound to make sure everything is okay. I was also taking monthly Zoladex shots to shut down my ovaries as I wasn't menopausal yet. I have had several blood tests to confirm the medication is working and I don't have any estrogen or whatever the hormones are called. There is a special hormone they look for estrodiol or something??? Have you thought about asking for a blood test to make sure your estrogen levels are down to an acceptable level which indicates medication is working? I found it very reassuring.