Pharmacology Fluoxymesterone

1 pharmacology

1.1 pharmacodynamics

1.1.1 11β-hsd inhibition
1.1.2 glucocorticoid activity


1.2 pharmacokinetics

pharmacology
pharmacodynamics

as aas, fluoxymesterone agonist of androgen receptor (ar), androgens testosterone , dht. substrate 5α-reductase testosterone, , potentiated in so-called androgenic tissues skin, hair follicles, , prostate gland. such, fluoxymesterone has relatively poor ratio of anabolic androgenic activity testosterone.

fluoxymesterone has been reported non-aromatizable due steric hindrance c11β hydroxyl group, , hence not considered have propensity producing estrogenic effects such gynecomastia or fluid retention. however, paradoxically, case report of severe fluoxymesterone-induced gynecomastia exists, , gynecomastia associated fluoxymesterone has been reported in other publications. fluoxymesterone thought possess little or no progestogenic activity.

because of presence of 17α-methyl group, metabolism of fluoxymesterone impeded, resulting in being orally active, although hepatotoxic.

11β-hsd inhibition

fluoxymesterone has been found act potent inhibitor of 11β-hydroxysteroid dehydrogenase type 2 (11β-hsd2) (ic50 = 60–630 nm), potency comparable of 11β-hsd2 inhibitor glycyrrhetinic acid. action of fluoxymesterone unique among aas , related 11β-hydroxyl group. 11β-hsd2 responsible inactivation of glucocorticoids cortisol , corticosterone (into cortisone , 11-dehydrocorticosterone, respectively). inhibition of 11β-hsd2 fluoxymesterone may result in mineralocorticoid receptor overactivation , associated side effects such hypertension , fluid retention, , has been hypothesized involved in cardiovascular , other adverse effects of fluoxymesterone.

glucocorticoid activity

unlike other aas, fluoxymesterone has structural features in common corticosteroids, including 9α-fluoro , 11β-hydroxy groups. in relation this, has weak (micromolar) potentially clinically significant affinity glucocorticoid receptor.

pharmacokinetics

fluoxymesterone has elimination half-life of approximately 9.2 hours, long relative of testosterone. in addition, unlike testosterone, fluoxymesterone has approximately 100% oral bioavailability, methyl group @ c17α position of fluoxymesterone inhibits hepatic metabolism enzymatic oxidation of 17β-hydroxyl, allowing absorption bloodstream transport around body.