Oral and Transdermal Estrogen Dose Equivalents

ORAL AND TRANSDERMAL ESTROGEN DOSE EQUIVALENTS
ORAL ESTROGENS		TRANSDERMAL ESTROGENS
• Plasma estrogen peaks & troughs • First pass through GI tract & liver (requires higher dose) • Increased hepatic enzymes, inflammatory markers • Increased triglycerides • Increased blood pressure • Reduced IGF‑1 • Decreased LDL cholesterol and increased HDL		• Serum E2 levels relatively constant • Does not pass through liver – lower doses required • No change in inflammatory markers • No change or decrease in triglycerides • Decrease in blood pressure • No effect on GH/IGF‑1 • Decreases LDL but no change in HDL
Active Ingredient	Brand	Source of Estrogen	Dose Equivalents
ORAL
equine conjugated estrogen	Premarin	Pregnant mares urine	0.625mg
esterified estrogens	Menest	Plant derived: Soy/Yams	0.625mg
estropipate	—	Plant derived: Yams	0.625mg
TRANSDERMAL
17-β-estradiol* patch (reservoir)	—	Plant derived: Soy/Yams	0.05mg
17-β estradiol* patch (matrix)	Alora	Plant derived: Soy/Yams	0.05mg
	Climara
	Vivelle-Dot
	Menostar
17-β estradiol* gel	Divigel	Plant derived: Soy/Yams, Sunflower seeds, Rapeseed, Poppy seeds, Pine trees	1g Divigel = 34pg/mL estradiol
	Elestrin	Plant derived: Soy, Rapeseed, Pine tree wood	1 pump (0.87g/d) = 0.0125mg estradiol 2 pumps (1.7g/d) = 0.0375mg estradiol
	Estrogel	Plant derived: Oil seed, Soy, Pine tree wood	No comparison studies done in U.S. Rate of delivery is 35µg/day which is therapeutically equivalent to Climara 50µg/day
17-β estradiol* spray	Evamist	Plant derived: Soy/Yams	No direct comparison trials. 1.53mg/spray. For 1 spray, 21µg gets to blood stream (29µg for 2 sprays, 40µg for 3 sprays). Premarin 0.625mg = just over 3 sprays of Evamist.
NOTES
The only formulation considered bioidentical, as defined by the 2007 Position Statement of the Endocrine Society. Matrix patch:* Estradiol is embedded in the adhesive layer that is applied directly to the skin. Reservoir patch: Estradiol is contained in a drug reservoir and its release is controlled by a copolymer membrane; contains more layers than matrix patch.
REFERENCES
Adapted from: Dong BJ. Hormonal Drugs: Female Sex Hormones in: Anderson PO, Knoben JE, Troutman WG, eds. Handbook of Clinical Drug Data. 10th ed. New York, N.Y. McGraw Hill; 2002:679−697. Kenigsberg L, Balachandar S, Prasad K, et al. Exogenous Pubertal Induction by Oral versus Transdermal Estrogen Therapy. J Pediatr Adolesc Gynecol. 2011 Nov 22. [Epub ahead of print]. (Rev. 5/2019)

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