The apparent volume of distribution of toremifene ranged from 457 to 958 L.

Metabolism
Toremifene is metabolized in the liver primarily by CYP3A4 and then undergoes secondary hydroxylation. The metabolites of toremifene include N-desmethyltoremifene, 4-hydroxytoremifene, and 4-hydroxy-N-desmethyltoremifene, among others. Ospemifene (deaminohydroxytoremifene) is also a major metabolite of toremifene. Elimination
The elimination half-life of toremifene is 3 to 7 days in healthy individuals. In people with impaired liver function, the half-life is 11 days. The elimination half-lives of the metabolites of toremifene are 5 to 21 days for N-desmethyltoremifene, 5 days for 4-hydroxytoremifene, and 4 days for ospemifene. The long elimination half-lives of toremifene and its metabolites are thought to be due to enterohepatic recirculation and high plasma protein binding. Toremifene is eliminated 70% in the feces, as metabolites. Chemistry
Toremifene, also known as 4-chlorotamoxifen, is a derivative of triphenylethylene and a close analogue of tamoxifen. It is also closely related to afimoxifene (4-hydroxytamoxifen) and ospemifene (deaminohydroxytoremifene). History
Toremifene was introduced in the United States in 1997. It was the first antiestrogen to be introduced in this country since tamoxifen in 1978. Society and culture
Generic names
Toremifene is the generic name of the drug and its INN and BAN, while toremifene citrate is its USAN and JAN and torémifène is its DCF. Brand names
Toremifene is marketed almost exclusively under the brand name Fareston. Availability
Toremifene is marketed widely throughout the world and is available in the United States, the United Kingdom, Ireland, many other European countries, South Africa, Australia, New Zealand, and elsewhere throughout the world.
Transient erythroblastopenia of childhood (TEC) is a slowly developing anemia of early childhood characterized by gradual onset of pallor. Signs and symptoms
Individuals with TEC have a median age of presentation of 18–26 months; however, the disorder may occur in infants younger than 6 months and in children as old as age 10 years. Because of the gradual onset of the anemia, children are often healthier than expected from their low hemoglobin levels. Cause
The cause of TEC is unknown, but it thought to be triggered by a viral infection. While rare cases have been attributed to infection with Parvovirus B19, the majority of cases are not related to Parvovirus infection. This is in contrast to transient aplastic crisis, seen in patients with hemoglobinopathies such as sickle cell disease, which is usually caused by Parvovirus infection. Diagnosis
Children typically present with a moderate normocytic anemia (usual range: Hemoglobin 5-8 g/dL) and reticulocytopenia. Mean corpuscular volume (MCV) is usually normal for age. Hemoglobin F levels are also typically normal. Prognosis
Most patients recover completely within 1–2 months. However many reported cases have lasted 18–24 months and longer. References
External links
ped/2279 at eMedicine