Estradiol undecylate
Pharmacodynamics
Esters of estradiol like estradiol undecylate are readily hydrolyzed prodrugs of estradiol, but have an extended duration when administered in oil via intramuscular injection due to a depot effect afforded by their fatty acid ester moiety.

Estradiol undecylate

Section Title: Pharmacodynamics
Table Section Text: Esters of estradiol like estradiol undecylate are readily hydrolyzed prodrugs of estradiol, but have an extended duration when administered in oil via intramuscular injection due to a depot effect afforded by their fatty acid ester moiety.

Estrogen	Type	Class	EPD (14 days)	CIC-D (month)	Duration

Estradiol	Bioidentical	Steroidal	40–60 mg	–	10 mg ≈ 2 days

Estradiol benzoate	Bioidentical	Steroidal	25–30 mg	5–10 mga	0.3–1.7 mg ≈ 2–3 days	5 mg ≈ 4–6 days

Estradiol benzoate (cryst. susp.)a	Bioidentical	Steroidal	20 mg	–	? mg ≈ 21 days

Estradiol dipropionate	Bioidentical	Steroidal	25–30 mg	–	5 mg ≈ 5–8 days

Estradiol valerate	Bioidentical	Steroidal	20–30 mg	5 mg	5 mg ≈ 7–8 days	10 mg ≈ 10–14 days

Estradiol cypionate	Bioidentical	Steroidal	25–30 mg	5 mg	5 mg ≈ 11–14 days

Estradiol enantate	Bioidentical	Steroidal	?	5–10 mg	10 mg ≈ 20–30 days

Estradiol undecylateb	Bioidentical	Steroidal	?	5–10 mga	10–12.5 mg ≈ 40–60 days	25–50 mg ≈ 60–120 days

Polyestradiol phosphate	Bioidentical	Steroidal	40–60 mg	–	40–50 mg ≈ 28–30 days	320 mg = >84 daysc

Polyestriol phosphate	Bioidentical	Steroidal	?	–	50 mg ≈ 30 days	80 mg ≈ 60 days

Diethylstilbestrol	Synthetic	Nonsteroidal	20 mg	–	3 mg ≈ 3 days

Diethylstilbestrol dipropionate	Synthetic	Nonsteroidal	12.5–15 mg	–	2.5 mg ≈ 5 days

Diethylstilbestrol dipropionate (cryst. susp.)a	Synthetic	Nonsteroidal	5 mg	–	? mg = 21–28 days

Dienestrol diacetate (cryst. susp.)a	Synthetic	Nonsteroidal	50 mg	–	?

Dimestrol	Synthetic	Nonsteroidal	20–40 mg	–	?

Hexestrol dipropionate	Synthetic	Nonsteroidal	25 mg	–	?

Note: All are via i.m. injection of oil solution unless noted otherwise.

Sentence(s)

A intramuscular injection of 10 to 12.5 mg estradiol undecylate has a duration of 40 to 60 days and of 25 to 50 mg estradiol undecylate has a duration of 2 to 4 months.

final_sentence: A intramuscular injection of 10 to 12.5 mg estradiol undecylate has a duration of 40 to 60 days and of 25 to 50 mg estradiol undecylate has a duration of 2 to 4 months.