<prompt> Tamoxifen is:Non steroidal antiprogesteroneNon steroidal antioestrogenicSynthetic progestogen norethindroneCompetitive inhibitor of the 5 a - reductase  <response>: Non steroidal antioestrogenic 306-Shaws 13th 186-S14th Tamoxifen - non steroidal antioestrogenic drug Clomiphene citrate - non steroidal anti oestrogens related to the diethylstilbestrol DES Mifepristone - Synthetic antiprogesterone Anti androgens - Cyproterone acetate, Spironolactone, Flutamide, FinastJeride Inhibitor of 5a- reductase 