Nolvadex-D (Tamoxifen Citrate) is not a steroid it is an anti-estrogen. it is a nonsteroidal agent which demonstrates potent anti-estrogenic properties. These anti-estrogenic effects are due to its ability to compete with estrogen for binding sites in target tissues such as in the breast. Medically, the affects of this drug make it very usefull in breast cancer patients.
Male bodybuilders however find this drug very affective in combating Gynocomastia (female breast tissue development) Gynocomastia is caused by excess estrogen in the male body. In the steroid user, this happens when anabolic steroids aromatize into Estrogens. This is not as odd as you may think. structurally these hormones are very similar. So with Nolvadex competing for any occupying estrogen receptors, the build up of tissue is greatly reduced and often avoided. Some believe Estrogen plays a role in keeping androgen receptors open. This may explain why Nolvadex would slightly hinder gains. Regardless of this effect Nolvadex is the most popular anti-estrogen used by athletes and many swear by it. You should take into account that many athletes find no need for Nolvadex While others absolutely need it to avoid a gyno problem.
You should be aware of how much you actually need of an ancillary drug like this before commiting to use it during a steroid cycle. Should it be needed, Nolvadex is very popular. Suggested dosage 2 x 20mg tablets a day with meals on a 2 week course is the standard period. Though the last 2 weeks of a steroid cycle and the 2 weeks after will be more beneficial.