These medications act on a protein in some cells of the body called the estrogen receptor.
The estrogen receptor binds to the hormoneestrogen, sending a signal to the cell.
This signal causes the cells to grow and can exert other effects.
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During pregnancy, the placenta releases estrogen.
Estrogen can impact tissues differently based on how their cells are programmed to react to it.
Estrogen affects the growth of mammary tissue, hair growth, and the menstrual cycle.
Estrogen Modulators
Compounds that act as modulators can attach to the estrogen receptor to change its activity.
In some tissues, including breast tissue, SERMs block the effects of estrogen.
In others, they act like estrogen, binding the receptor.
Different SERMs are active in various tissues.
When estrogen changes in the body lead to an illness, SERMs may be a treatment option.
These illnesses includeestrogen receptor-positive (ER+) breast cancers, osteoporosis, andmenopause(the cessation of menstruation).
These differences play a role in who gets prescribed these medications and for which conditions.
Tamoxifen (Nolvadex, Soltamox)
Tamoxifenis a SERM used as hormone therapy to treat breast cancer.
Alternate names for tamoxifen include the brand names Nolvadex and Soltamox.
Tamoxifen is taken as a daily pill by mouth.
It is also available as a liquid.
It can also decrease the risk of developing invasive breast cancer for postmenopausal people at high risk.
Raloxifene should not be prescribed to people who menstruate who have not reached menopause.
Healthcare providers recommend getting a lot of foods rich incalciumandvitamin Dwhile taking raloxifene.
It can prevent low bone density from becoming osteoporosis and reduces the risk of vertebral fractures.
They act by turning down the bone cells in charge of breaking down bone and reabsorbing its nutrients.
SERMs for Breast Cancer
Tamoxifen, as hormone therapy, cantreat ER+ breast cancer.
Healthcare providers will sometimes prescribe toremifene in place of tamoxifen.
All SERMs, including raloxifene, can help prevent breast cancer in high-risk people.
Either tamoxifen or raloxifene may reduce the risk of developing breast cancer by 40%.
SERMs vs. Aromatase Inhibitors
SERMS are similar to another class of drugs called aromatase inhibitors.
Aromatase inhibitors are another pop in of hormone therapy.
They are used more often for people who have gone through menopause.
Side effects of SERMs may include symptoms of menopause.
These can include:
Other more dangerous side effects can happen but are rare.
These include blood clotsknown asdeep vein thrombosisin the leg andpulmonary embolismin the lungsleading to serious problems and even death.
Raloxifene Side Effects
Raloxifene may cause side effects.
The tumor flare can lead to a high calcium level in the blood that is hard to control.
Uterine cancer: Some SERMs increase the risk of developing uterine cancer and endometrial pre-cancers.
Other side effects of toremifene include:
Are SERMs Safe?
SERMs are generally safe for use according to prescribing guidelines.
They can prevent breast cancer and treat it and osteoporosis.
Theyre generally safe but may have some serious or mild side effects.
They dont change the estrogen level in the body but can impact how the body responds to the hormone.
People with dense breast tissue have more connective tissue than fatty tissue.
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MedlinePlus.Estrogen and bazedoxifene.
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