This category covers two distinct drug classes that are often grouped together but work differently. Selective oestrogen receptor modulators — tamoxifen at 20mg and clomifene at 50mg — act on oestrogen receptors directly. Aromatase inhibitors — anastrozole at 1mg, letrozole at 2.5mg and exemestane at 25mg — act on the enzyme instead, and differ among themselves: anastrozole and letrozole bind reversibly while exemestane is a steroidal inhibitor that binds irreversibly.

All five are supplied as tablets in tubs of 50. The strength differences between them are large — a factor of fifty between the anastrozole and clomifene tablets — so the per-tablet figure on each listing matters more here than in any other category.