Two medications used to treat breast cancer are tamoxifen and aromatase inhibitors. Both of these medications are considered endocrine therapy. Treatments that stop estrogen or progesterone hormones from attaching to cancer cell’s receptors are called hormone or endocrine therapy. These medications have side effects which lead to sexual dysfunction because they decrease circulating estrogen levels (aromatase inhibitors) and/or change estrogen’s effect on target organs (tamoxifen).
Aromatase inhibitors stop estrogen from being produced in postmenopausal women. Aromatase inhibitors work by blocking the enzyme aromatase, which turns the hormone androgen into small amounts of estrogen in the body. This means that less estrogen is available to stimulate the growth of hormone-receptor-positive breast cancer cells. (breastcancer.org)
Tamoxifen is a selective estrogen receptor modulator (SERM). Because it's a SERM, it selectively either blocks or activates estrogen's action on specific cells. While tamoxifen blocks estrogen's action on breast cells, it activates estrogen's action in bone and liver cells.(breastcancer.org)
Low circulating estrogen in the body can lead to symptoms commonly seen with menopausal and post-menopausal women such as painful sex due to lack of lubrication or thinning tissues.
Decrease in vaginal lubrication or thinning of tissues can cause painful intercourse because of increased friction or tearing of tissues. Understanding your medications and knowing their side effects can better equip you to avoid painful experiences related to your sex life. The good news is that there are non-hormonal options available to you to address these lubrication and fragile tissue concerns such as vaginal moisturizers and lubricants. Reach out to your pelvic health therapist to discover what you can do.