Tibolone: a tissue-specific approach to the menopause

Tibolone, a synthetic steroid that is used for hormone replacement in menop ausal women. is metabolized to three primary active agents: 3-alpha-hydroxy -tibolone: 3-beta-hydroxy-tibolone and Delta (4)-tibolone. It can exhibit o estrogenic. progestogenic or androgenic activity, depending primarily on th e target tissue involved for this reason, tibolone is said to have tissue-s pecific activity. Oestrogenic effects on vasomotor symptoms, the vagina and bone mean that tibolone is effective in the management of climacteric symp toms and bone loss. However. it does not cause oestrogenic stimulation of t he endometrium or breast tissue. thus reducing the risk for side effects su ch as bleeding and breast tenderness. (C) 2001 The European Society of Card iology.