Identification
- Summary
Estriol is a weak estrogen used to treat vaginal dryness and estrogen deficiency conditions, such as vaginitis and vulvar itching.
- Generic Name
- Estriol
- DrugBank Accession Number
- DB04573
- Background
A hydroxylated metabolite of estradiol or estrone that has a hydroxyl group at C3-beta, 16-alpha, and 17-beta position. Estriol is a major urinary estrogen. During pregnancy, large amount of estriol is produced by the placenta. Isomers with inversion of the hydroxyl group or groups are called epiestriol. Though estriol is used as part of the primarily North American phenomenon of bioidentical hormone replacement therapy, it is not approved for use by the FDA or Health Canada. It is however available in the United States by prescription filled only by compounding pharmacies. It has also been approved and marketed throughout Europe and Asia for approximately 40 years for the treatment of post-menopausal hot flashes.
- Type
- Small Molecule
- Groups
- Approved, Investigational, Vet approved
- Structure
Structure for Estriol (DB04573)
- Weight
- Average: 288.3814
Monoisotopic: 288.172544634 - Chemical Formula
- C18H24O3
- Synonyms
- (16α,17β)-estra-1,3,5(10)-triene-3,16,17-triol
- 1,3,5(10)-Estratriene-3,16-alpha,17beta-triol
- 16-alpha-Hydroxyestradiol
- 16alpha-hydroxyestradiol
- 16α-hydroxyestradiol
- 16α,17β-estriol
- 3,16alpha,17beta-Trihydroxy-delta(1,3,5)-estratriene
- Estriol
- Oestriol
- Östriol
- Trihydroxyestrin
Pharmacology
- Indication
Used as a test to determine the general health of an unborn fetus.
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- Associated Therapies
- Contraindications & Blackbox Warnings
Avoid life-threatening adverse drug eventsImprove clinical decision support with information on contraindications & blackbox warnings, population restrictions, harmful risks, & more.Avoid life-threatening adverse drug events & improve clinical decision support.- Pharmacodynamics
Estriol (also oestriol) is one of the three main estrogens produced by the human body. It is only produced in significant amounts during pregnancy as it is made by the placenta. In pregnant women with multiple sclerosis (MS), estriol reduces the disease's symptoms noticeably, according to researchers at UCLA's Geffen Medical School.
- Mechanism of action
Estriol levels can be measured to give an indication of the general health of the fetus. DHEA-S is produced by the adrenal cortex of the fetus. This is converted to estriol by the placenta. If levels of "unconjugated estriol" are abnormally low in a pregnant woman, this may indicate a problem with the development of the child. The drug interacts with a target cell receptor. When the estrogen receptor has bound its ligand it can enter the nucleus of the target cell, and regulate gene transcription which leads to formation of messenger RNA. The mRNA interacts with ribosomes to produce specific proteins that express the effect of estriol upon the target cell. Estrogens increase the hepatic synthesis of sex hormone binding globulin (SHBG), thyroid-binding globulin (TBG), and other serum proteins and suppress follicle-stimulating hormone (FSH) from the anterior pituitary.
Target Actions Organism AEstrogen receptor alpha agonistHumans UEstrogen receptor beta agonistHumans USex hormone-binding globulin Not Available Humans - Absorption
Not Available
- Volume of distribution
Not Available
- Protein binding
Not Available
- Metabolism
Hover over products below to view reaction partners
- Route of elimination
Not Available
- Half-life
Not Available
- Clearance
Not Available
- Adverse Effects
Improve decision support & research outcomesWith structured adverse effects data, including: blackbox warnings, adverse reactions, warning & precautions, & incidence rates.Improve decision support & research outcomes with our structured adverse effects data.- Toxicity
ORAL (LD50): Acute: >2000 mg/kg [Rat].
- Pathways
Pathway Category Estrone Metabolism Metabolic - Pharmacogenomic Effects/ADRs
- Not Available
Interactions
- Drug Interactions
- This information should not be interpreted without the help of a healthcare provider. If you believe you are experiencing an interaction, contact a healthcare provider immediately. The absence of an interaction does not necessarily mean no interactions exist.
Drug Interaction Integrate drug-drug
interactions in your softwareAbciximab Estriol may decrease the anticoagulant activities of Abciximab. Aceclofenac Aceclofenac may increase the thrombogenic activities of Estriol. Acenocoumarol Estriol may decrease the anticoagulant activities of Acenocoumarol. Acetohexamide The therapeutic efficacy of Acetohexamide can be decreased when used in combination with Estriol. Adalimumab Estriol may increase the thrombogenic activities of Adalimumab. Aducanumab Estriol may increase the thrombogenic activities of Aducanumab. Alemtuzumab Estriol may increase the thrombogenic activities of Alemtuzumab. Alirocumab Estriol may increase the thrombogenic activities of Alirocumab. Allantoin The therapeutic efficacy of Allantoin can be decreased when used in combination with Estriol. Alteplase Estriol may decrease the anticoagulant activities of Alteplase. 
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- Not Available
Products
Drug product information from 10+ global regionsOur datasets provide approved product information including:dosage, form, labeller, route of administration, and marketing period.Access drug product information from over 10 global regions.- International/Other Brands
- Aacifemine (Organon) / Colpoestriol (Temis-Lostalo) / Estriel / Ovestin (Merck Sharp & Dohme) / Synapause E (Organon)
- Over the Counter Products
Name Dosage Strength Route Labeller Marketing Start Marketing End Region Image Advanced Formula Estro-Life Cream 1.69 mg/1mL Topical Smoky Mountain Naturals, LLC - DBA SMNutrition 2022-04-01 Not applicable US 
Estriol 5.0 Cream Cream 5 mg/85g Transdermal SHYNE BRANDS 2021-06-15 Not applicable US Estro-Life Cream 1.69 mg/1mL Topical Smoky Mountain Naturals, LLC - DBA SMNutrition 2022-04-01 Not applicable US - Mixture Products
Name Ingredients Dosage Route Labeller Marketing Start Marketing End Region Image BiEST 2.5 Estrogen Cream Estriol (2 mg/85g) + Estradiol (0.5 mg/85g) Cream Transdermal SHYNE BRANDS 2021-06-15 Not applicable US BiEST 2.5 Estrogen Cream (Lavender scented) Estriol (2 mg/85g) + Estradiol (0.5 mg/85g) Cream Transdermal SHYNE BRANDS 2021-06-15 Not applicable US BiEST 5.0 Estrogen Cream Estriol (4 mg/85g) + Estradiol (1 mg/85g) Cream Transdermal SHYNE BRANDS 2021-06-15 Not applicable US Gynoflor - Vaginaltabletten Estriol (0.03 mg) + Lactobacillus acidophilus (50 mg) Tablet Vaginal Gedeon Richter Plc 1990-02-09 Not applicable Austria 
GYNOFLOR 50 MG/0.03 MG VAJİNAL TABLET, 12 ADET Estriol (0.03 mg) + Lactobacillus acidophilus (50 mg) Suppository Vaginal ABDİ İBRAHİM İLAÇ SAN. VE TİC. A.Ş. 2020-08-14 Not applicable Turkey 
GYNOFLOR 50 MG/0.03 MG VAJİNAL TABLET, 6 ADET Estriol (0.03 mg) + Lactobacillus acidophilus (50 mg) Suppository Vaginal ABDİ İBRAHİM İLAÇ SAN. VE TİC. A.Ş. 2020-08-14 Not applicable Turkey ไกโนฟลอร์ Estriol (0.03 mg) + Lactobacillus acidophilus (100000000 cfu) Tablet Vaginal บริษัท ดีเคเอสเอช (ประเทศไทย) จำกัด 2011-09-16 Not applicable Thailand 
- Unapproved/Other Products
Name Ingredients Dosage Route Labeller Marketing Start Marketing End Region Image Advanced Formula Estro-Life Estriol (1.69 mg/1mL) Cream Topical Smoky Mountain Naturals, LLC - DBA SMNutrition 2022-04-01 Not applicable US BiEST 2.5 Estrogen Cream Estriol (2 mg/85g) + Estradiol (0.5 mg/85g) Cream Transdermal SHYNE BRANDS 2021-06-15 Not applicable US BiEST 2.5 Estrogen Cream (Lavender scented) Estriol (2 mg/85g) + Estradiol (0.5 mg/85g) Cream Transdermal SHYNE BRANDS 2021-06-15 Not applicable US BiEST 5.0 Estrogen Cream Estriol (4 mg/85g) + Estradiol (1 mg/85g) Cream Transdermal SHYNE BRANDS 2021-06-15 Not applicable US Estriol 5.0 Cream Estriol (5 mg/85g) Cream Transdermal SHYNE BRANDS 2021-06-15 Not applicable US Estro-Life Estriol (1.69 mg/1mL) Cream Topical Smoky Mountain Naturals, LLC - DBA SMNutrition 2022-04-01 Not applicable US
Categories
- ATC Codes
- G03CC06 — Estriol
- G03CC — Estrogens, combinations with other drugs
- G03C — ESTROGENS
- G03 — SEX HORMONES AND MODULATORS OF THE GENITAL SYSTEM
- G — GENITO URINARY SYSTEM AND SEX HORMONES
- Drug Categories
- Estradiol Congeners
- Estranes
- Estrenes
- Estrogens
- Fused-Ring Compounds
- Genito Urinary System and Sex Hormones
- Gonadal Hormones
- Gonadal Steroid Hormones
- Hormones
- Hormones, Hormone Substitutes, and Hormone Antagonists
- Natural and Semisynthetic Estrogens, Plain
- P-glycoprotein inducers
- P-glycoprotein substrates
- Sex Hormones and Modulators of the Genital System
- Steroids
- Thyroxine-binding globulin inducers
- Chemical TaxonomyProvided by Classyfire
- Description
- This compound belongs to the class of organic compounds known as estrogens and derivatives. These are steroids with a structure containing a 3-hydroxylated estrane.
- Kingdom
- Organic compounds
- Super Class
- Lipids and lipid-like molecules
- Class
- Steroids and steroid derivatives
- Sub Class
- Estrane steroids
- Direct Parent
- Estrogens and derivatives
- Alternative Parents
- 3-hydroxysteroids / 17-hydroxysteroids / 16-alpha-hydroxysteroids / Phenanthrenes and derivatives / Tetralins / 1-hydroxy-2-unsubstituted benzenoids / Secondary alcohols / Cyclic alcohols and derivatives / 1,2-diols / Hydrocarbon derivatives
- Substituents
- 1,2-diol / 1-hydroxy-2-unsubstituted benzenoid / 16-alpha-hydroxysteroid / 16-hydroxysteroid / 17-hydroxysteroid / 3-hydroxysteroid / Alcohol / Aromatic homopolycyclic compound / Benzenoid / Cyclic alcohol
- Molecular Framework
- Aromatic homopolycyclic compounds
- External Descriptors
- 17beta-hydroxy steroid, 3-hydroxy steroid, 16alpha-hydroxy steroid (CHEBI:27974) / C18 steroids (estrogens) and derivatives, Estrane and derivatives, Estrogens (C05141) / C18 steroids (estrogens) and derivatives (LMST02010003)
- Affected organisms
- Humans and other mammals
Chemical Identifiers
- UNII
- FB33469R8E
- CAS number
- 50-27-1
- InChI Key
- PROQIPRRNZUXQM-ZXXIGWHRSA-N
- InChI
- InChI=1S/C18H24O3/c1-18-7-6-13-12-5-3-11(19)8-10(12)2-4-14(13)15(18)9-16(20)17(18)21/h3,5,8,13-17,19-21H,2,4,6-7,9H2,1H3/t13-,14-,15+,16-,17+,18+/m1/s1
- IUPAC Name
- (1R,2R,3aS,3bR,9bS,11aS)-11a-methyl-1H,2H,3H,3aH,3bH,4H,5H,9bH,10H,11H,11aH-cyclopenta[a]phenanthrene-1,2,7-triol
- SMILES
- [H][C@@]12C[C@@H](O)[C@H](O)[C@@]1(C)CC[C@]1([H])C3=C(CC[C@@]21[H])C=C(O)C=C3
References
- Synthesis Reference
James V. Freeman, Gary M. Johnson, "Synthesis of 6.alpha.-functionalized estriol haptens and protein conjugates thereof." U.S. Patent US5902888, issued June, 1973.
US5902888- General References
- External Links
- Human Metabolome Database
- HMDB0000153
- KEGG Drug
- D00185
- KEGG Compound
- C05141
- PubChem Compound
- 5756
- PubChem Substance
- 46505881
- ChemSpider
- 5553
- BindingDB
- 50410506
- 4094
- ChEBI
- 27974
- ChEMBL
- CHEMBL193482
- ZINC
- ZINC000003815418
- Therapeutic Targets Database
- DAP001019
- PharmGKB
- PA164769104
- PDBe Ligand
- ESL
- Wikipedia
- Estriol
- PDB Entries
- 1x8v / 3q95
- MSDS
- Download (75.9 KB)
Clinical Trials
- Clinical Trials
Phase Status Purpose Conditions Count 4 Completed Supportive Care Atrophic Vaginitis / Endometrial Hyperplasia / Pelvic Organ Prolapse (POP) 1 4 Completed Treatment Vulvo Vaginal Atrophy 1 4 Unknown Status Prevention Urinary Tract Infection 1 4 Unknown Status Treatment Prolapse Genital 1 3 Completed Treatment Vulvo Vaginal Atrophy 2 3 Terminated Treatment Atrophic Vaginitis 1 2 Completed Treatment Epistaxis / Hereditary Haemorrhagic Telangiectasia (HHT) 1 2 Completed Treatment Relapsing Remitting Multiple Sclerosis (RRMS) 1 2 Completed Treatment Vulvo Vaginal Atrophy 2 2 Terminated Treatment Menopause 1
Pharmacoeconomics
- Manufacturers
- Not Available
- Packagers
- Jiangxi Yuneng Pharmchem Co. Ltd.
- NutriScience Innovations LLC
- Dosage Forms
Form Route Strength Insert Vaginal Cream Transdermal Gel Vaginal 50 mcg/g Gel Vaginal 50 MICROGRAMMI/G Cream Vaginal 0.0125 % Insert Vaginal 1 MG Tablet Vaginal Cream Vaginal 0.05 g Cream Vaginal 0.100 g Insert Vaginal 3.500 mg Cream Transdermal 5 mg/85g Cream Vaginal 50 g Cream Vaginal 0.5 MG/G Cream Topical 1.69 mg/1mL Cream Vaginal 0.1 g Suppository Vaginal Capsule Vaginal Gel Vaginal Suppository Vaginal Cream Vaginal 1 mg/g Suppository Vaginal 0.5 MG Suppository Vaginal 0.03 MG Cream Vaginal 1.0 MG/G Insert Vaginal 3.5 mg Cream; gel Vaginal Tablet Oral 1 MG Cream Vaginal Tablet Oral Tablet Oral 2 mg Cream Vaginal 100 mg Insert Vaginal 0.5 mg Cream Vaginal 1.000 mg Insert Vaginal 0.500 mg Cream Vaginal 1 MG/1G - Prices
- Not Available
- Patents
- Not Available
Properties
- State
- Solid
- Experimental Properties
Property Value Source melting point (°C) 82-86 Organon Laboratories Limited, England; British Patent 879,014; October 4, 1961. logP 2.45 HANSCH,C ET AL. (1995) - Predicted Properties
Property Value Source Water Solubility 0.119 mg/mL ALOGPS logP 2.54 ALOGPS logP 2.67 Chemaxon logS -3.4 ALOGPS pKa (Strongest Acidic) 10.33 Chemaxon pKa (Strongest Basic) -3.2 Chemaxon Physiological Charge 0 Chemaxon Hydrogen Acceptor Count 3 Chemaxon Hydrogen Donor Count 3 Chemaxon Polar Surface Area 60.69 Å2 Chemaxon Rotatable Bond Count 0 Chemaxon Refractivity 81.27 m3·mol-1 Chemaxon Polarizability 33.08 Å3 Chemaxon Number of Rings 4 Chemaxon Bioavailability 1 Chemaxon Rule of Five Yes Chemaxon Ghose Filter Yes Chemaxon Veber's Rule No Chemaxon MDDR-like Rule No Chemaxon - Predicted ADMET Features
Property Value Probability Human Intestinal Absorption + 0.9966 Blood Brain Barrier + 0.7057 Caco-2 permeable + 0.7591 P-glycoprotein substrate Substrate 0.7862 P-glycoprotein inhibitor I Non-inhibitor 0.9208 P-glycoprotein inhibitor II Non-inhibitor 0.9805 Renal organic cation transporter Non-inhibitor 0.8619 CYP450 2C9 substrate Non-substrate 0.7536 CYP450 2D6 substrate Non-substrate 0.7993 CYP450 3A4 substrate Substrate 0.6892 CYP450 1A2 substrate Non-inhibitor 0.6618 CYP450 2C9 inhibitor Non-inhibitor 0.9399 CYP450 2D6 inhibitor Non-inhibitor 0.9619 CYP450 2C19 inhibitor Non-inhibitor 0.7086 CYP450 3A4 inhibitor Non-inhibitor 0.8932 CYP450 inhibitory promiscuity Low CYP Inhibitory Promiscuity 0.9152 Ames test Non AMES toxic 0.9133 Carcinogenicity Non-carcinogens 0.9147 Biodegradation Not ready biodegradable 0.9811 Rat acute toxicity 1.9758 LD50, mol/kg Not applicable hERG inhibition (predictor I) Weak inhibitor 0.948 hERG inhibition (predictor II) Inhibitor 0.7684
Spectra
- Mass Spec (NIST)
- Download (2.96 KB)
- Spectra
Targets
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- Kind
- Protein
- Organism
- Humans
- Pharmacological action
- Yes
- Actions
- Agonist
- General Function
- Zinc ion binding
- Specific Function
- Nuclear hormone receptor. The steroid hormones and their receptors are involved in the regulation of eukaryotic gene expression and affect cellular proliferation and differentiation in target tissu...
- Gene Name
- ESR1
- Uniprot ID
- P03372
- Uniprot Name
- Estrogen receptor
- Molecular Weight
- 66215.45 Da
References
- Kind
- Protein
- Organism
- Humans
- Pharmacological action
- Unknown
- Actions
- Agonist
- General Function
- Zinc ion binding
- Specific Function
- Nuclear hormone receptor. Binds estrogens with an affinity similar to that of ESR1, and activates expression of reporter genes containing estrogen response elements (ERE) in an estrogen-dependent m...
- Gene Name
- ESR2
- Uniprot ID
- Q92731
- Uniprot Name
- Estrogen receptor beta
- Molecular Weight
- 59215.765 Da
References
- Mishra RG, Stanczyk FZ, Burry KA, Oparil S, Katzenellenbogen BS, Nealen ML, Katzenellenbogen JA, Hermsmeyer RK: Metabolite ligands of estrogen receptor-beta reduce primate coronary hyperreactivity. Am J Physiol Heart Circ Physiol. 2006 Jan;290(1):H295-303. Epub 2005 Sep 30. [Article]
- Kind
- Protein
- Organism
- Humans
- Pharmacological action
- Unknown
- General Function
- Androgen binding
- Specific Function
- Functions as an androgen transport protein, but may also be involved in receptor mediated processes. Each dimer binds one molecule of steroid. Specific for 5-alpha-dihydrotestosterone, testosterone...
- Gene Name
- SHBG
- Uniprot ID
- P04278
- Uniprot Name
- Sex hormone-binding globulin
- Molecular Weight
- 43778.755 Da
References
- Hong H, Branham WS, Ng HW, Moland CL, Dial SL, Fang H, Perkins R, Sheehan D, Tong W: Human sex hormone-binding globulin binding affinities of 125 structurally diverse chemicals and comparison with their binding to androgen receptor, estrogen receptor, and alpha-fetoprotein. Toxicol Sci. 2015 Feb;143(2):333-48. doi: 10.1093/toxsci/kfu231. Epub 2014 Oct 27. [Article]
Transporters
- Kind
- Protein
- Organism
- Humans
- Pharmacological action
- Unknown
- Actions
- Inhibitor
- General Function
- Sodium-independent organic anion transmembrane transporter activity
- Specific Function
- Mediates the Na(+)-independent transport of organic anions such as sulfobromophthalein (BSP) and conjugated (taurocholate) and unconjugated (cholate) bile acids (By similarity). Selectively inhibit...
- Gene Name
- SLCO1A2
- Uniprot ID
- P46721
- Uniprot Name
- Solute carrier organic anion transporter family member 1A2
- Molecular Weight
- 74144.105 Da
References
- Kanai N, Lu R, Bao Y, Wolkoff AW, Vore M, Schuster VL: Estradiol 17 beta-D-glucuronide is a high-affinity substrate for oatp organic anion transporter. Am J Physiol. 1996 Feb;270(2 Pt 2):F326-31. [Article]
- Kind
- Protein
- Organism
- Humans
- Pharmacological action
- Unknown
- Actions
- SubstrateInducer
- General Function
- Xenobiotic-transporting atpase activity
- Specific Function
- Energy-dependent efflux pump responsible for decreased drug accumulation in multidrug-resistant cells.
- Gene Name
- ABCB1
- Uniprot ID
- P08183
- Uniprot Name
- Multidrug resistance protein 1
- Molecular Weight
- 141477.255 Da
References
- Kim WY, Benet LZ: P-glycoprotein (P-gp/MDR1)-mediated efflux of sex-steroid hormones and modulation of P-gp expression in vitro. Pharm Res. 2004 Jul;21(7):1284-93. [Article]
Drug created at September 07, 2007 21:04 / Updated at June 12, 2021 10:53