Fareston (toremifene citrate)

Dosage of toremifene citrate is expressed in terms of toremifene.

Because only minimal amounts of toremifene (about 10%) are excreted in urine, and because the pharmacokinetics of toremifene citrate and N-demethyltoremifene, an active metabolite of the drug, are not altered in patients with renal impairment, dosage adjustment is not necessary in such patients.

Toremifene is extensively metabolized in the liver, and the drug is eliminated more slowly in patients with hepatic impairment (e.g., cirrhosis or fibrosis). In patients with hepatic impairment, toremifene should be used with caution and liver function should be monitored carefully; although the manufacturer makes no specific recommendation, reduction of toremifene dosage may be necessary.

Adverse effects requiring discontinuance of therapy, including pulmonary embolism, myocardial infarction, ischemic attack, thrombophlebitis, nausea and vomiting, anorexia, fatigue, depression, lethargy, and arthritis, occurred in approximately 1% of patients receiving toremifene 60 mg daily in clinical trials.

Toremifene citrate is administered orally. Food does not affect the absorption of toremifene, and the drug may be administered without regard to meals.

No dosing information is available for this tab.

No dosing information is available for this tab.

Formal studies of drug interactions with toremifene have not been performed to date.

There are no contraindication interactions for this drug.

There are no severe interactions for this drug.

There are no moderate interactions for this drug.

There is no enhanced messaging for this drug.

There are no contraindication contraindications for this drug.

There are no severe contraindications for this drug.

There are no moderate contraindications for this drug.

There is no enhanced messaging for this drug.

There are no severe adverse reactions for this drug.

There are no less severe adverse reactions for this drug.

No enhanced messaging available.

No enhanced messaging available.

Toremifene can cause fetal toxicity when administered to pregnant women, but potential benefits from use of the drug may be acceptable in certain conditions despite the possible risks to the fetus.

Embryotoxicity and fetotoxicity were demonstrated in rabbits receiving toremifene doses of at least 1.25 mg/kg and 2.5 mg/kg daily (approximately one-third and two-thirds, respectively, the daily maximum recommended human dosage on a mg/m2 basis); fetal anomalies included incomplete ossification and anencephaly. In reproduction studies in rats using toremifene dosages of at least 1 mg/kg daily (about one-fourth the daily maximum recommended human dosage on a mg/m2 basis) administered during the period of organogenesis, toremifene was embryotoxic and fetotoxic, resulting in intrauterine mortality, increased resorption, reduced fetal weight, and fetal anomalies (including malformation of limbs, incomplete ossification, misshapen bones, ribs/spine anomalies, hydroureter, hydronephrosis, testicular displacement, and subcutaneous edema). Fetal anomalies may have occurred as a consequence of maternal toxicity. Toremifene has been shown to cross the placenta and accumulate in the fetus in rodents.

In models of fetal reproductive tract development in rodents, toremifene caused inhibition of uterine development in female pups in a manner similar to tamoxifen and diethylstilbestrol (DES; no longer commercially available in the US); the clinical importance of this finding is not known.

There are no adequate and well-controlled studies using toremifene in pregnant women. Toremifene is labeled for use in postmenopausal women. Toremifene should be used during pregnancy only in life-threatening situations or severe disease for which safer drugs cannot be used or are ineffective. When the drug is administered during pregnancy or if the patient becomes pregnant while receiving the drug, the patient should be informed of the potential hazard to the fetus and the potential risk for loss of the pregnancy.

It is not known if toremifene is distributed into milk in humans; however, the drug is distributed into milk in rats. Because of the potential for serious adverse reactions to toremifene in nursing infants, a decision should be made whether to discontinue nursing or the drug, taking into account the importance of the drug to the woman.

No enhanced messaging available.