Pharmacodynamics<unk>  is a progestogen, or an agonist of the progesterone receptor (PR). It has very high affinity for the PR, about 588 to 660% of that of progesterone. This is greater than that of almost all other widely used progestins, with the exception of the 19-nortestosterone derivative gestodene (which has about 864% of the affinity of progesterone). In accordance with its very high affinity for the PR,<unk>  is described as a very potent progestogen, showing significant clinical effectiveness in the treatment of endometriosis at a dosage of only 0.1 mg/day, and is the most potent progestin of the 19-norprogesterone group. Like other progestogens,<unk>  has functional antiestrogenic effects in certain tissues such as the endometrium and has antigonadotropic effects. The endometrial transformation dosage of<unk>  is 0.25 to 0.5 mg/day and its ovulation-inhibiting dosage is 0.5 mg/day. In addition to its affinity for the PR,<unk>  has moderate affinity for the mineralocorticoid receptor (42–120% of that of aldosterone), weak to very weak affinity for the glucocorticoid and androgen receptors (9–13% of that of dexamethasone and 1–2.4% of that of testosterone, respectively), and no affinity for the estrogen receptor (less than 0.02% of that of estradiol). In accordance, it possesses weak antimineralocorticoid activity, very weak antiandrogenic activity, and no androgenic, estrogenic, glucocorticoid, antiglucocorticoid, or mineralocorticoid activity. As such, it is a selective and mostly pure progestogen. Unlike progesterone,<unk>  does not metabolize into neurosteroids and hence does not influence GABAA receptor signaling or produce sedative side effects. The antiandrogenic potency of<unk>  in animals is about 30% of that of cyproterone acetate. Pharmacokinetics The oral bioavailability of<unk>  is about 100%. Following a single oral dose of<unk> , peak serum concentrations occur within 0.5 hours and are 12–15 ng/mL (35–44 nmol/L) for a 0.5 mg dose and 25 ng/mL (73 nmol/L) for a 1 mg dose. Circulating levels of<unk>  increase proportionally across dosages of 0.25 to 1 mg/day. Steady-state levels of<unk>  are achieved within 3 days of daily administration. The plasma protein binding of<unk>  is 98%; it is bound to albumin.<unk>  is metabolized mainly via hydroxylation. The 1β- and 6β-hydroxy metabolites of<unk>  are progestogens with considerable potency similarly and show little or no affinity to other steroid hormone receptors. The elimination half-life of<unk>  is between 12 and 20 hours, with an average of about 13.8 to 15.6 hours.
Trimegestone
Trengestone
Demegestone
Oak wilt
Cradle cap
Racquet nail
Flat wart
Cramp-ring