My Experience with Fulvestrant: The Ups, the Downs, and What Helps

A little while into my treatment, my doctor told me I was stable enough to get off of fulvestrant injections.

What is fulvestrant?

What is fulvestrant? Well, consider yourself lucky not to know. Fulvestrant is an injection that's administered on each side of your buttocks into the muscle. It's injected slowly and hurts when it's done.¹

Fulvestrant is in a class of medications called estrogen receptor antagonists. It works by blocking estrogen production in cancer cells in the body. This can slow or stop the growth of some breast tumors that need estrogen to grow.¹

This is about all I know about this particular drug. I don't know much; I know where it goes, how often it's administered, and what it does.

Why I went off (and back on) fulvestrant

My doctor in Seattle took me off of this medication a couple of years ago so that when it might be necessary again, I could add it back into my treatment plan. That day came when my most recent scan showed some cancer progression. I've got a couple of spots lighting up in various areas of my skeleton and liver. We added fulvestrant injections back in hopes that I wouldn't have to change this line of treatment right away completely.

I wasn't excited to hear we were adding fulvestrant back in, but it could help ease back into more treatments without making drastic changes. I collaborate with my healthcare team here in Phoenix, and it's something I like about my cancer care. I feel heard by my providers, and my quality of life is important to them. Their consideration and collaboration helps me feel normal.

Side effects of fulvestrant: My experience

I don't do much to prepare for these injections. I ended up getting sick with COVID-19 at the beginning of the month, which pushed back the treatment.

A few things to note about fulvestrant's side effects are that it can cause mood swings. This can be tricky to navigate. When I was first on this treatment, I was newly diagnosed with metastatic breast cancer. A lot was going on at once, and it was hard to manage my emotions. These days, I am a lot more settled in my diagnosis. I feel more stable in my emotions, and I am in therapy. I can better manage mood swings now compared to when I first took fulvestrant.

Another side effect is joint pain. I wasn't prepared for what that would mean for the rod in my arm. I have arthritis around the socket, and it can be really painful. Honestly, I forgot how painful it can be.

How I manage side effects

I can manage joint pain with light exercise, and lidocaine patches, heat, and ice can reduce the arthritis pain in my shoulder.

Something that not many people talk about with this medicine is the smell. It comes out in your sweat and your urine. At least, in my case, it does. I hydrate, hydrate, hydrate so that I can have this move through me relatively quickly. It's not necessarily unpleasant; I just find it weird.

I hope to continue to have smooth injection days in the future!