Class | Examples | RE complex retention | Pharmacodynamic profile | Uterine effects |
---|---|---|---|---|
Short-acting (a.k.a. "weak" or "impeded") |
Estriol ⢠16-Epiestriol ⢠17Îą-Estradiol ⢠ent-Estradiol ⢠16-Ketoestradiol ⢠Dimethylstilbestrol ⢠meso-Butestrol | Short (1â4 hours) | Single or once-daily injections: partial agonist or antagonist | Early responsesa |
Implant or multiple injections per day: full agonist | Early and late responsesb | |||
Long-acting | A. Estradiol ⢠Estrone ⢠Ethinylestradiol ⢠Diethylstilbestrol ⢠Hexestrol | Intermediate (6â24 hours) | Single or once-daily injections: full agonist | Early and late responses |
B. Clomifene ⢠Nafoxidine ⢠Nitromifene ⢠Tamoxifen | Long (>24â48 hours) | Single injection: agonist Repeated injections: antagonist |
Early and late responses | |
Footnotes: a = Early responses occur after 0â6 hours and include water imbibition, hyperemia, amino acid and nucleotide uptake, activation of RNA polymerases I and II, and stimulation of induced protein, among others. b = Late responses occur after 6â48 hours and include cellular hypertrophy and hyperplasia and sustained RNA polymerase I and II activity, among others. Sources: [1] [2] [3] [4] [5] [6] [7] |
Class | Examples | RE complex retention | Pharmacodynamic profile | Uterine effects |
---|---|---|---|---|
Short-acting (a.k.a. "weak" or "impeded") |
Estriol ⢠16-Epiestriol ⢠17Îą-Estradiol ⢠ent-Estradiol ⢠16-Ketoestradiol ⢠Dimethylstilbestrol ⢠meso-Butestrol | Short (1â4 hours) | Single or once-daily injections: partial agonist or antagonist | Early responsesa |
Implant or multiple injections per day: full agonist | Early and late responsesb | |||
Long-acting | A. Estradiol ⢠Estrone ⢠Ethinylestradiol ⢠Diethylstilbestrol ⢠Hexestrol | Intermediate (6â24 hours) | Single or once-daily injections: full agonist | Early and late responses |
B. Clomifene ⢠Nafoxidine ⢠Nitromifene ⢠Tamoxifen | Long (>24â48 hours) | Single injection: agonist Repeated injections: antagonist |
Early and late responses | |
Footnotes: a = Early responses occur after 0â6 hours and include water imbibition, hyperemia, amino acid and nucleotide uptake, activation of RNA polymerases I and II, and stimulation of induced protein, among others. b = Late responses occur after 6â48 hours and include cellular hypertrophy and hyperplasia and sustained RNA polymerase I and II activity, among others. Sources: [1] [2] [3] [4] [5] [6] [7] |