Clomiphene citrate: the changing landscape

ABSTRACT

Ovulatory dysfunction is one of the leading causes of female infertility. Clomiphene citrate has emerged as a boon in the induction of ovulation in the human female. Clomiphene results in many adverse effects some of which are documented, and some reported spontaneously. Clomiphene citrate is a non-racemic mixture of two isomers, zuclomiphene and enclomiphene, having individual and opposite biological actions. It is accepted that cis isomer (zuclomiphene) is estrogenic and trans isomer (enclomiphene) is anti-estrogenic. Zuclomiphene does not have any ovulation-induction propertybut gets accumulated for a longer time in the human body and it has more agonistic activity than enclomiphene. Thus, Zuclomiphene may be responsible for the adverse effects by clomiphene citrate. Enclomiphene is being explored for its potential use in male as well as female infertility. Trails are underway to explore its effectiveness and safety in various disorders. This article highlights the pharmacology of Clomiphene with respect to its isomers and the potential uses of enclomiphene based on evidences available.