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Fareston (toremifene) Disease Interactions

There are 4 disease interactions with Fareston (toremifene):


Toremifene (Includes Fareston) ↔ Qt Prolongation

Severe Potential Hazard, Moderate plausibility

Applies to: Long QT Syndrome, Hypokalemia, Magnesium Imbalance, Congestive Heart Failure

Toremifene has shown to prolong the QTc interval in a dose and concentration related manner, which can result in Torsade de Pointes (ventricular tachycardia), syncope, seizure, and/or death. Toremifene should not be prescribed to patients with congenital or acquired QT prolongation, uncorrected hypokalemia or uncorrected hypomagnesemia. Caution is advised in patients with congestive heart failure, and patients taking other drugs that can prolong the QT interval.


Toremifene (Includes Fareston) ↔ Endometrial Hyperplasia

Moderate Potential Hazard, Moderate plausibility

Applies to: Endometrial Dysplasia

Endometrial cancer, endometrial hyperplasia, hypertrophy, and uterine polyps have been reported in some patients treated with toremifene. Long-term use of toremifene has not been established in patients with preexisting endometrial hyperplasia. All patients should have baseline and annual gynecological examinations. In particular, patients at high risk of endometrial cancer should be closely monitored.


  1. "Product Information. Fareston (toremifene)." Schering Laboratories, Kenilworth, NJ.

Toremifene (Includes Fareston) ↔ Hepatotoxicity

Moderate Potential Hazard, Moderate plausibility

Applies to: Liver Disease

Hepatotoxicity, hepatitis, and non-alcoholic fatty liver disease have been reported in clinical trials and postmarketing with toremifene. Liver function tests should be performed periodically. Caution is advised in patients with any hepatic impairment.


Toremifene (Includes Fareston) ↔ Thromboembolism

Moderate Potential Hazard, Moderate plausibility

Applies to: History - Thrombotic/Thromboembolic Disorder, Thrombotic/Thromboembolic Disorder

Thromboembolic events such as thrombophlebitis and pulmonary embolism have been noted during toremifene therapy. Patients with an active or past history of thromboembolic events should generally not be administered toremifene.


  1. "Product Information. Fareston (toremifene)." Schering Laboratories, Kenilworth, NJ.

Fareston (toremifene) drug Interactions

There are 461 drug interactions with Fareston (toremifene)

Fareston (toremifene) alcohol/food Interactions

There is 1 alcohol/food interaction with Fareston (toremifene)

Drug Interaction Classification

The classifications below are a general guideline only. It is difficult to determine the relevance of a particular drug interaction to any individual given the large number of variables.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No information available.

Do not stop taking any medications without consulting your healthcare provider.

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