Dexamethasone

hormone · endocrine · immune-hematologic · Oral · IV · Intramuscular

Dexamethasone, a hormone. 9α-fluorinated, 16α-methylated synthetic GR agonist — long biologic half-life (~36–54 h), negligible mineralocorticoid… Oral half-life 4 h.

9α-fluorinated, 16α-methylated synthetic GR agonist — long biologic half-life (~36–54 h), negligible mineralocorticoid activity. Pure anti-inflammatory / immunosuppressive profile without sodium retention. HPA-axis suppression at supraphysiologic doses is profound (a single 1 mg dose suppresses ACTH → cortisol for >24 h — the overnight dexamethasone suppression test).

Pharmacokinetics

• Oral — t½ 4 h · F 78% · ka 4 h⁻¹ · Vd 50 L
• IV — t½ 4 h · F 100% · Vd 50 L
• Intramuscular — t½ 4 h · F 100% · ka 7.78 h⁻¹ · Vd 50 L

Sources: PMID:15634032, PMID:7578014, PMID:2316228