Toremifene or Fareston is an estrogen antagonist used to treat metastatic breast cancer.
The hormone estrogen is considered to be involved in breast cancer, thus blocking the hormone's effects seem logical. Toremifene or Fareston is antagonist of estrogen and is similar to another estrogen antagonist, tamoxifen.
Toremifene or Fareston's most common side effects are hot flushes, nausea, and vomiting - in up to 25% of people using the drug. These effects are thought be related to the estrogen antagonism.
Toremifene or Fareston can affect various components of the blood, monitoring of blood is required and people with existing conditions involving the blood need to carefully followed.
As with other additive hormonal therapy, elevated calcium levels may be seen, and people at risk should be carefully followed.
Because Toremifene or Fareston is hormonal therapy, menstrual cycles changes and/or uterine changes can occur. Women at risk for these changes must be monitored closely and if changes do occur they should be evaluated fully.
Toremifene or Fareston is often given with chemotherapeutic drugs and together they can increase the risk for thromboembolic events, that is blood clots. In combination with the blood thinner, warfarin, Toremifene or Fareston can prolong bleeding times.
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The relevant product monographs must be regarded as the appropriate sources of prescribing information.