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British National Formulary
Levonorgestrel
BNF
Drug monograph — bnf.nice.org.ukSource: British National Formulary, NICE. Joint Formulary Committee. Contains public sector information licensed under the Open Government Licence v3.0.
NICE clinical guidance(7)
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Pharmacology and chemical data from DrugBank
Key facts
Drug status
Approved
Major interactions
None known
Half-life
20-60 hours
Mechanism
Mechanism of action on ovulation Oral contraceptives containing levonorgestre…
Food interactions
2 warnings
Human targets
6 targets
Data: DrugBank · CC BY-NC 4.0
Pharmacokinetics at a glance
Absorption
2-3 days
Orally administered levonorgestrel is absorbed in the gastrointestinal tract while levonorgestrel administered through an IUD device is absorbed in the endometrium.…
Half-life
0.75 mg
The elimination half-life of a 0.75 mg dose of 1.5 mg of levonorgestrel ranges between 20-60 hours post-administration.
[A181976]…
[A181976]…
Protein binding
97.5-99%
The protein binding of levonorgestrel ranges from 97.5-99%, and it is mainly bound to sex hormone-binding globulin (SHBG).…
Volume of distribution
1.5 mg
One pharmacokinetic study determined a mean steady-state volume of distribution of 1.5…
Metabolism
After absorption of the oral emergency contraceptive preparation, levonorgestrel is conjugated and forms a large number of sulfate conjugates.…
Elimination
45%
Approximately 45% of an oral levonorgestrel dose and its conjugated or sulfate metabolites are found to be excreted in the urine.…
Clearance
4.8 L/h
Clearance was found to 4.8 L/h in healthy female volunteers with a normal BMI, and 7.70-8.51…
Pharmacokinetic data: DrugBank · CC BY-NC 4.0
Status:
Approved
Investigational
Small molecule
About this compound
Levonorgestrel (LNG) is a synthetic progestogen similar to [Progesterone] used in contraception and hormone therapy.[A181988,T659] Also known as Plan B, it is used as a single agent in emergency contraception, and as a hormonal contraceptive released from an intrauterine device, commonly referred to as an IUD. Some of these devices are known as Jaydess, Kyleena, and Mirena. A subdermal implant of levonorgestrel that slowly releases the hormone over a long-term period is also available.[L7823] In addition to the above uses, levonorgestrel is used as a component of long-term combination contraceptives.[A181991][L7760][L7778]
Globally, levonorgestrel is the most commonly used emergency contraceptive. It was initially granted FDA approval in 1982 and was the first emergency contraceptive containing only progesterone, showing high levels of efficacy and a lack of estrogenic adverse effects when compared to older emergency contraceptive regimens.[A181976][A181994][L7760]
Globally, levonorgestrel is the most commonly used emergency contraceptive. It was initially granted FDA approval in 1982 and was the first emergency contraceptive containing only progesterone, showing high levels of efficacy and a lack of estrogenic adverse effects when compared to older emergency contraceptive regimens.[A181976][A181994][L7760]
Properties:
solid
Avg. mass: 312.45 Da
DrugBank indication
Emergency contraception
Levonorgestrel, in the single-agent emergency contraceptive form, is indicated for the prevention of pregnancy after the confirmed or suspected failure of contraception methods or following unprotected intercourse. It is distributed by prescription for patients under 17, and over the counter for those above this age.
[L7760]
This levonorgestrel-only form of contraception is not indicated for regular contraception and must be taken as soon as possible within 72 hours after intercourse.
[A181976][L7760]
It has shown a lower efficacy when it is used off label within 96 hours.T659
Long-term contraception or nonemergency contraception
In addition to the above indication in emergency contraception, levonorgestrel is combined with other contraceptives in contraceptive formulations designed for regular use, for example with ethinyl estradiol.
[L7766]
It is used in various hormone-releasing intrauterine devices for long-term contraception ranging for a duration of 3-5 years.
[L7778][L7781][L7787]
Product labeling for Mirena specifically mentions that it is recommended in women who have had at least 1 child and can be indicated for the prevention of pregnancy for up to 8 years.
[L7778][L42950]
A subdermal implant is also available for the prevention of pregnancy for up to 5 years.
[L7823]
Hormone therapy and off-label uses
Levonorgestrel is prescribed in combination with estradiol as hormone therapy during menopause to manage vasomotor symptoms and to prevent osteoporosis.
[L7805]
Off-label, levonorgestrel may be used to treat menorrhagia, endometrial hyperplasia, and endometriosis.T659
Levonorgestrel, in the single-agent emergency contraceptive form, is indicated for the prevention of pregnancy after the confirmed or suspected failure of contraception methods or following unprotected intercourse. It is distributed by prescription for patients under 17, and over the counter for those above this age.
[L7760]
This levonorgestrel-only form of contraception is not indicated for regular contraception and must be taken as soon as possible within 72 hours after intercourse.
[A181976][L7760]
It has shown a lower efficacy when it is used off label within 96 hours.T659
Long-term contraception or nonemergency contraception
In addition to the above indication in emergency contraception, levonorgestrel is combined with other contraceptives in contraceptive formulations designed for regular use, for example with ethinyl estradiol.
[L7766]
It is used in various hormone-releasing intrauterine devices for long-term contraception ranging for a duration of 3-5 years.
[L7778][L7781][L7787]
Product labeling for Mirena specifically mentions that it is recommended in women who have had at least 1 child and can be indicated for the prevention of pregnancy for up to 8 years.
[L7778][L42950]
A subdermal implant is also available for the prevention of pregnancy for up to 5 years.
[L7823]
Hormone therapy and off-label uses
Levonorgestrel is prescribed in combination with estradiol as hormone therapy during menopause to manage vasomotor symptoms and to prevent osteoporosis.
[L7805]
Off-label, levonorgestrel may be used to treat menorrhagia, endometrial hyperplasia, and endometriosis.T659
Also known as(63)
(-)-13-Ethyl-17-hydroxy-18,19-dinor-17alpha-pregn-4-en-20-yn-3-one
(8R,9S,10R,13S,14S,17R)-13-ethyl-17-ethynyl-17-hydroxy- 1,2,6,7,8,9,10,11,12,13,14,15,16, 17- tetradecahydrocyclopenta[a] phenanthren-3-one
13-beta-Ethyl-17alpha-ethynyl-17beta-hydroxygon-4-en-3-one
13-Ethyl-17-alpha-ethynyl-17-beta-hydroxy-4-gonen-3-one
13-Ethyl-17-alpha-ethynylgon-4-en-17-beta-ol-3-one
17-alpha-Ethinyl-13-beta-ethyl-17-beta-hydroxy-4-estren-3-one
17-alpha-Ethynyl-13-ethyl-19-nortestosterone
17-Ethynyl-18-methyl-19-nortestosterone
Dosage forms(77)
Tablet (Oral) — 0.02 mg
Kit (Oral)
Insert (Vaginal) — 20 mcg/24hr
Intrauterine device (Intrauterine) — 52 mg
Tablet (Oral) — 0.750 mg
Patch (Transdermal)
Kit; patch (Transdermal)
Tablet (Oral) — 1.500 mg
Molecular properties(19)
Drug interactions(746)
Known interactions with other medications. Always consult a healthcare professional.
The therapeutic efficacy of Levonorgestrel can be decreased when used in combination with Acitretin.
Atazanavir
Unknown severity
The serum concentration of Levonorgestrel can be increased when it is combined with Atazanavir.
Boceprevir
Unknown severity
The serum concentration of Levonorgestrel can be increased when it is combined with Boceprevir.
Prucalopride
Unknown severity
The serum concentration of Levonorgestrel can be decreased when it is combined with Prucalopride.
Sugammadex
Unknown severity
The serum concentration of Levonorgestrel can be decreased when it is combined with Sugammadex.
Thalidomide
Moderate
Levonorgestrel may increase the thrombogenic activities of Thalidomide.
Ulipristal
Moderate
The therapeutic efficacy of Levonorgestrel can be decreased when used in combination with Ulipristal.
Ursodeoxycholic acid
Moderate
The therapeutic efficacy of Ursodeoxycholic acid can be decreased when used in combination with Levonorgestrel.
The therapeutic efficacy of Glycochenodeoxycholic Acid can be decreased when used in combination with Levonorgestrel.
Cholic Acid
Moderate
The therapeutic efficacy of Cholic Acid can be decreased when used in combination with Levonorgestrel.
Glycocholic acid
Moderate
The therapeutic efficacy of Glycocholic acid can be decreased when used in combination with Levonorgestrel.
Deoxycholic acid
Moderate
The therapeutic efficacy of Deoxycholic acid can be decreased when used in combination with Levonorgestrel.
Taurocholic acid
Moderate
The therapeutic efficacy of Taurocholic acid can be decreased when used in combination with Levonorgestrel.
Obeticholic acid
Moderate
The therapeutic efficacy of Obeticholic acid can be decreased when used in combination with Levonorgestrel.
Tauroursodeoxycholic acid
Moderate
The therapeutic efficacy of Tauroursodeoxycholic acid can be decreased when used in combination with Levonorgestrel.
The therapeutic efficacy of Bamet-UD2 can be decreased when used in combination with Levonorgestrel.
The therapeutic efficacy of cis-Diamminechlorocholylglycinateplatinum(II) can be decreased when used in combination with Levonorgestrel.
Dehydrocholic acid
Moderate
The therapeutic efficacy of Dehydrocholic acid can be decreased when used in combination with Levonorgestrel.
Hyodeoxycholic Acid
Moderate
The therapeutic efficacy of Hyodeoxycholic Acid can be decreased when used in combination with Levonorgestrel.
The therapeutic efficacy of Aramchol can be decreased when used in combination with Levonorgestrel.
Ox bile extract
Moderate
The therapeutic efficacy of Ox bile extract can be decreased when used in combination with Levonorgestrel.
Chenodeoxycholic acid
Moderate
The therapeutic efficacy of Chenodeoxycholic acid can be decreased when used in combination with Levonorgestrel.
The therapeutic efficacy of Taurochenodeoxycholic acid can be decreased when used in combination with Levonorgestrel.
Tranexamic acid
Moderate
Levonorgestrel may increase the thrombogenic activities of Tranexamic acid.
The serum concentration of Levonorgestrel can be decreased when it is combined with Clobazam.
Colestipol
Moderate
Colestipol can cause a decrease in the absorption of Levonorgestrel resulting in a reduced serum concentration and potentially a decrease in efficacy.
Sevelamer can cause a decrease in the absorption of Levonorgestrel resulting in a reduced serum concentration and potentially a decrease in efficacy.
Colesevelam
Moderate
Colesevelam can cause a decrease in the absorption of Levonorgestrel resulting in a reduced serum concentration and potentially a decrease in efficacy.
Cholestyramine
Moderate
Cholestyramine can cause a decrease in the absorption of Levonorgestrel resulting in a reduced serum concentration and potentially a decrease in efficacy.
Griseofulvin
Moderate
The metabolism of Levonorgestrel can be increased when combined with Griseofulvin.
Tixocortol
Unknown severity
The serum concentration of Tixocortol can be increased when it is combined with Levonorgestrel.
Fluperolone
Unknown severity
The serum concentration of Fluperolone can be increased when it is combined with Levonorgestrel.
Fluclorolone
Unknown severity
The serum concentration of Fluclorolone can be increased when it is combined with Levonorgestrel.
Flunisolide
Unknown severity
The serum concentration of Flunisolide can be increased when it is combined with Levonorgestrel.
Beclomethasone dipropionate
Unknown severity
The serum concentration of Beclomethasone dipropionate can be increased when it is combined with Levonorgestrel.
Betamethasone
Unknown severity
The serum concentration of Betamethasone can be increased when it is combined with Levonorgestrel.
Fluocinolone acetonide
Unknown severity
The serum concentration of Fluocinolone acetonide can be increased when it is combined with Levonorgestrel.
Triamcinolone
Unknown severity
The serum concentration of Triamcinolone can be increased when it is combined with Levonorgestrel.
Prednisone
Unknown severity
The serum concentration of Prednisone can be increased when it is combined with Levonorgestrel.
Hydrocortisone
Unknown severity
The serum concentration of Hydrocortisone can be increased when it is combined with Levonorgestrel.
Prednisolone
Unknown severity
The serum concentration of Prednisolone can be increased when it is combined with Levonorgestrel.
Methylprednisolone
Unknown severity
The serum concentration of Methylprednisolone can be increased when it is combined with Levonorgestrel.
Corticotropin
Unknown severity
The serum concentration of Corticotropin can be increased when it is combined with Levonorgestrel.
Cortisone acetate
Unknown severity
The serum concentration of Cortisone acetate can be increased when it is combined with Levonorgestrel.
Fluprednidene
Unknown severity
The serum concentration of Fluprednidene can be increased when it is combined with Levonorgestrel.
Meprednisone
Unknown severity
The serum concentration of Meprednisone can be increased when it is combined with Levonorgestrel.
Dexamethasone isonicotinate
Unknown severity
The serum concentration of Dexamethasone isonicotinate can be increased when it is combined with Levonorgestrel.
Deflazacort
Unknown severity
The serum concentration of Deflazacort can be increased when it is combined with Levonorgestrel.
Cortivazol
Unknown severity
The serum concentration of Cortivazol can be increased when it is combined with Levonorgestrel.
Prednylidene
Unknown severity
The serum concentration of Prednylidene can be increased when it is combined with Levonorgestrel.
Showing 50 of 746 interactions
Food & lifestyle interactions
Advice
Take at the same time every day.
Advice
Take with or without food. The effect of food on absorption has not been evaluated.
Toxicity & overdose
The oral LD50 in rats is greater than 5000 mg/kg.
[L7790]
An overdose of this drug, like other contraceptives, may cause nausea and withdrawal bleeding. Provide symptomatic treatment in the case of a levonorgestrel overdose and contact the local poison control center. There is no specific antidote for a levonorgestrel overdose.
[L7760][L7793][L7796]
[L7790]
An overdose of this drug, like other contraceptives, may cause nausea and withdrawal bleeding. Provide symptomatic treatment in the case of a levonorgestrel overdose and contact the local poison control center. There is no specific antidote for a levonorgestrel overdose.
[L7760][L7793][L7796]
How it works
Mechanism of action
Mechanism of action on ovulation
Oral contraceptives containing levonorgestrel suppress gonadotropins, inhibiting ovulation. Specifically, levonorgestrel binds to progesterone and androgen receptors and slows the release of gonadotropin-releasing hormone (GnRH) from the hypothalamus. This process results in the suppression of the normal physiological luteinizing hormone (LH) surge that precedes ovulation. It inhibits the rupture of follicles and viable egg release from the ovaries. Levonorgestrel has been proven to be more effective when administered before ovulation.T659
Mechanism of action in cervical mucus changes
Similar to other levonorgestrel-containing contraceptives, the intrauterine (IUD) forms of levonorgestrel likely prevent pregnancy by increasing the thickness of cervical mucus, interfering with the movement and survival of sperm, and inducing changes in the endometrium, where a fertilized ovum is usually implanted.[L7778][L7781] Levonorgestrel is reported to alter the consistency of mucus in the cervix, which interferes with sperm migration into the uterus for fertilization. Levonorgestrel is not effective after implantation has occurred.[A181976]
Interestingly, recent evidence has refuted the commonly believed notion that levonorgestrel changes the consistency of cervical mucus when it is taken over a short-term period, as in emergency contraception. Over a long-term period, however, levonorgestrel has been proven to thicken cervical mucus.[A181976] The exact mechanism of action of levonorgestrel is not completely understood and remains a topic of controversy and ongoing investigation.[A181976][L7760]
*Effects on implantation
The effects of levonorgestrel on endometrial receptivity are unclear, and the relevance of this mechanism to the therapeutic efficacy of levonorgestrel is contentious.[A175372][A218666] Prescribing information for levonorgestrel IUDs state that they exert local morphological changes to the endometrium (e.g. stromal pseudodecidualization, glandular atrophy) that may play a role in their contraceptive activity.[L7778][L7781]
Mechanism of action in hormone therapy**
When combined with estrogens for the treatment of menopausal symptoms and prevention of osteoporosis, levonorgestrel serves to lower the carcinogenic risk of unopposed estrogen therapy via the inhibition of endometrial proliferation. Unregulated endometrial proliferation sometimes leads to endometrial cancer after estrogen use.[L7808]
Oral contraceptives containing levonorgestrel suppress gonadotropins, inhibiting ovulation. Specifically, levonorgestrel binds to progesterone and androgen receptors and slows the release of gonadotropin-releasing hormone (GnRH) from the hypothalamus. This process results in the suppression of the normal physiological luteinizing hormone (LH) surge that precedes ovulation. It inhibits the rupture of follicles and viable egg release from the ovaries. Levonorgestrel has been proven to be more effective when administered before ovulation.T659
Mechanism of action in cervical mucus changes
Similar to other levonorgestrel-containing contraceptives, the intrauterine (IUD) forms of levonorgestrel likely prevent pregnancy by increasing the thickness of cervical mucus, interfering with the movement and survival of sperm, and inducing changes in the endometrium, where a fertilized ovum is usually implanted.[L7778][L7781] Levonorgestrel is reported to alter the consistency of mucus in the cervix, which interferes with sperm migration into the uterus for fertilization. Levonorgestrel is not effective after implantation has occurred.[A181976]
Interestingly, recent evidence has refuted the commonly believed notion that levonorgestrel changes the consistency of cervical mucus when it is taken over a short-term period, as in emergency contraception. Over a long-term period, however, levonorgestrel has been proven to thicken cervical mucus.[A181976] The exact mechanism of action of levonorgestrel is not completely understood and remains a topic of controversy and ongoing investigation.[A181976][L7760]
*Effects on implantation
The effects of levonorgestrel on endometrial receptivity are unclear, and the relevance of this mechanism to the therapeutic efficacy of levonorgestrel is contentious.[A175372][A218666] Prescribing information for levonorgestrel IUDs state that they exert local morphological changes to the endometrium (e.g. stromal pseudodecidualization, glandular atrophy) that may play a role in their contraceptive activity.[L7778][L7781]
Mechanism of action in hormone therapy**
When combined with estrogens for the treatment of menopausal symptoms and prevention of osteoporosis, levonorgestrel serves to lower the carcinogenic risk of unopposed estrogen therapy via the inhibition of endometrial proliferation. Unregulated endometrial proliferation sometimes leads to endometrial cancer after estrogen use.[L7808]
Pharmacodynamics
Levonorgestrel prevents pregnancy by interfering with ovulation, fertilization, and implantation. The levonorgestrel-only containing emergency contraceptive tablet is 89% effective if it is used according to prescribing information within 72 hours after intercourse.[A181976][A181988] The intrauterine and implantable devices releasing levonorgestrel are more than 99% in preventing pregnancy.[A182123][L7778][L7781] Levonorgestrel utilized as a component of hormonal therapy helps to prevent endometrial carcinoma associated with unopposed estrogen administration.[A182042]
Pharmacokinetics
How the body processes this drug — absorption, distribution, metabolism, and elimination
Absorption
Orally administered levonorgestrel is absorbed in the gastrointestinal tract while levonorgestrel administered through an IUD device is absorbed in the endometrium. Levonorgestrel is absorbed immediately in the interstitial fluids when it is inserted as a subdermal implant.
[L7823]
After insertion of the subdermal implant, the Cmax of levonorgestrel is attained within 2-3 days.
[L7823]
The Cmax following one dose of 0.75 mg of oral levonorgestrel is reached within the hour after administration, according to one reference.
[A181976]
In a pharmacokinetic study of 1.5 mg of levonorgestrel in women with a normal BMI and those considered to be obese (BMI>30), mean Cmax was found to be 16.2 ng/mL and 10.5 ng/mL respectively. Tmax was found to be 2 hours for those with normal BMI and 2.5 hours for patients with increased BMI.
[A181985]
The bioavailability of levonorgestrel approaches 100%.
[L7793]
Mean AUC has been shown to be higher in patients with a normal BMI, measuring at 360.1 h × ng/mL versus a range of 197.28 to 208.1 h × ng/mL in an obese group of patients. Obesity may contribute to decreased efficacy of levonorgestrel in contraception.
[A181985]
[L7823]
After insertion of the subdermal implant, the Cmax of levonorgestrel is attained within 2-3 days.
[L7823]
The Cmax following one dose of 0.75 mg of oral levonorgestrel is reached within the hour after administration, according to one reference.
[A181976]
In a pharmacokinetic study of 1.5 mg of levonorgestrel in women with a normal BMI and those considered to be obese (BMI>30), mean Cmax was found to be 16.2 ng/mL and 10.5 ng/mL respectively. Tmax was found to be 2 hours for those with normal BMI and 2.5 hours for patients with increased BMI.
[A181985]
The bioavailability of levonorgestrel approaches 100%.
[L7793]
Mean AUC has been shown to be higher in patients with a normal BMI, measuring at 360.1 h × ng/mL versus a range of 197.28 to 208.1 h × ng/mL in an obese group of patients. Obesity may contribute to decreased efficacy of levonorgestrel in contraception.
[A181985]
Half-life
The elimination half-life of a 0.75 mg dose of 1.5 mg of levonorgestrel ranges between 20-60 hours post-administration.
[A181976]
A pharmacokinetic study of women with a normal BMI and BMI over revealed an elimination half-life of 29.7 h and 41.0-46.4 hours, respectively.
[A181985]
Another pharmacokinetic study revealed a mean elimination half-life of 24.4 hours after a 0.75 mg dose of levonorgestrel was administered to 16 patients.
[A181979]
[A181976]
A pharmacokinetic study of women with a normal BMI and BMI over revealed an elimination half-life of 29.7 h and 41.0-46.4 hours, respectively.
[A181985]
Another pharmacokinetic study revealed a mean elimination half-life of 24.4 hours after a 0.75 mg dose of levonorgestrel was administered to 16 patients.
[A181979]
Protein binding
The protein binding of levonorgestrel ranges from 97.5-99%, and it is mainly bound to sex hormone-binding globulin (SHBG). Levonorgestrel is also bound to albumin.
[A10375][L7760][L7781][L7823]
The prescribing information for the implanted levonorgestrel indicates that the concentration of sex hormone-binding globulin (SHBG) is reduced in the span of a few days after levonorgestrel administration, decreasing the levels of the drug.
[L7823]
[A10375][L7760][L7781][L7823]
The prescribing information for the implanted levonorgestrel indicates that the concentration of sex hormone-binding globulin (SHBG) is reduced in the span of a few days after levonorgestrel administration, decreasing the levels of the drug.
[L7823]
Volume of distribution
One pharmacokinetic study determined a mean steady-state volume of distribution of 1.5 mg of levonorgestrel to be 162.2 L in those with normal BMI and in the range of 404.7 L to 466.4 L in obese patients with a body mass index of at least 30.
[A181985]
Mean volume of distribution in 16 patients receiving 0.75 mg of levonorgestrel in another pharmacokinetic study was 260 L.
[A181979]
The Plan B one-step FDA label reports an apparent volume of distribution of 1.8 L/kg.
[L7760]
[A181985]
Mean volume of distribution in 16 patients receiving 0.75 mg of levonorgestrel in another pharmacokinetic study was 260 L.
[A181979]
The Plan B one-step FDA label reports an apparent volume of distribution of 1.8 L/kg.
[L7760]
Metabolism
After absorption of the oral emergency contraceptive preparation, levonorgestrel is conjugated and forms a large number of sulfate conjugates. In addition, glucuronide conjugates have been identified in the plasma.
[A182033]
High levels of conjugated and unconjugated 3α, 5β-tetrahydrolevonorgestrel are found in the plasma. The entire metabolic pathway for levonorgestrel has not been studied, however, 16β-hydroxylation is one pathway that has been identified.
[L7823]
Small quantities of 3α, 5α tetrahydrolevonorgestrel and 16βhydroxylevonorgestrel are also formed.
[L7760]
No active metabolites have been identified.
[L7793]
The rate of metabolism may be considerably different according to the patient and may explain a wide variation in levonorgestrel clearance.
[L7760]
Liver CYP3A4 and CYP3A5 hepatic enzymes are reported to be involved in the metabolism of levonorgestrel.
[A182084][L7760]
[A182033]
High levels of conjugated and unconjugated 3α, 5β-tetrahydrolevonorgestrel are found in the plasma. The entire metabolic pathway for levonorgestrel has not been studied, however, 16β-hydroxylation is one pathway that has been identified.
[L7823]
Small quantities of 3α, 5α tetrahydrolevonorgestrel and 16βhydroxylevonorgestrel are also formed.
[L7760]
No active metabolites have been identified.
[L7793]
The rate of metabolism may be considerably different according to the patient and may explain a wide variation in levonorgestrel clearance.
[L7760]
Liver CYP3A4 and CYP3A5 hepatic enzymes are reported to be involved in the metabolism of levonorgestrel.
[A182084][L7760]
Route of elimination
Approximately 45% of an oral levonorgestrel dose and its conjugated or sulfate metabolites are found to be excreted in the urine. Approximately 32% of an orally ingested dose is found excreted in feces, primarily in the form of glucuronide conjugates of levonorgestrel.
[L7760]
[L7760]
Clearance
Clearance was found to 4.8 L/h in healthy female volunteers with a normal BMI, and 7.70-8.51 L/h in obese patients after a single 1.5 mg dose.
[A181985]
After a 0.75 mg dose of levonorgestrel in 16 patients in another pharmacokinetic study, mean clearance was calculated at 7.06 L/h.
[A181979]
Following levonorgestrel implant removal, the serum concentration falls below 100 pg/mL within the first 96 hours and further falls below the sensitivity of detection within the range of 5 days to 2 weeks.
[L7823]
[A181985]
After a 0.75 mg dose of levonorgestrel in 16 patients in another pharmacokinetic study, mean clearance was calculated at 7.06 L/h.
[A181979]
Following levonorgestrel implant removal, the serum concentration falls below 100 pg/mL within the first 96 hours and further falls below the sensitivity of detection within the range of 5 days to 2 weeks.
[L7823]
Drug targets(6)
Proteins and enzymes this drug interacts with in the body
Progesterone receptor
PGR
modulator
Specific functionATPase binding
Cellular location
Nucleus
General function & pharmacology
The steroid hormones and their receptors are involved in the regulation of eukaryotic gene expression and affect cellular proliferation and differentiation in target tissues. Depending on the isoform, progesterone receptor functions as a transcriptional activator or repressor
3-oxo-5-alpha-steroid 4-dehydrogenase 1
SRD5A1
inhibitor
Specific function3-oxo-5-alpha-steroid 4-dehydrogenase (NADP+) activity
Cellular location
Microsome membrane
General function & pharmacology
Converts testosterone into 5-alpha-dihydrotestosterone and progesterone or corticosterone into their corresponding 5-alpha-3-oxosteroids. It plays a central role in sexual differentiation and androgen physiology
Estrogen receptor
ESR1
other/unknown
Specific function14-3-3 protein binding
Cellular location
Nucleus
General function & pharmacology
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 tissues. Ligand-dependent nuclear transactivation involves either direct homodimer binding to a palindromic estrogen response element (ERE) sequence or association with other DNA-binding transcription factors, such as AP-1/c-Jun, c-Fos, ATF-2, Sp1 and Sp3, to mediate ERE-independent signaling.
Ligand binding induces a conformational change allowing subsequent or combinatorial association with multiprotein coactivator complexes through LXXLL motifs of their respective components. Mutual transrepression occurs between the estrogen receptor (ER) and NF-kappa-B in a cell-type specific manner. Decreases NF-kappa-B DNA-binding activity and inhibits NF-kappa-B-mediated transcription from the IL6 promoter and displace RELA/p65 and associated coregulators from the promoter.
Recruited to the NF-kappa-B response element of the CCL2 and IL8 promoters and can displace CREBBP. Present with NF-kappa-B components RELA/p65 and NFKB1/p50 on ERE sequences. Can also act synergistically with NF-kappa-B to activate transcription involving respective recruitment adjacent response elements; the function involves CREBBP.
Can activate the transcriptional activity of TFF1. Also mediates membrane-initiated estrogen signaling involving various kinase cascades. Essential for MTA1-mediated transcriptional regulation of BRCA1 and BCAS3 .
PMID:17922032
Maintains neuronal survival in response to ischemic reperfusion injury when in the presence of circulating estradiol (17-beta-estradiol/E2) (By similarity)
Ligand binding induces a conformational change allowing subsequent or combinatorial association with multiprotein coactivator complexes through LXXLL motifs of their respective components. Mutual transrepression occurs between the estrogen receptor (ER) and NF-kappa-B in a cell-type specific manner. Decreases NF-kappa-B DNA-binding activity and inhibits NF-kappa-B-mediated transcription from the IL6 promoter and displace RELA/p65 and associated coregulators from the promoter.
Recruited to the NF-kappa-B response element of the CCL2 and IL8 promoters and can displace CREBBP. Present with NF-kappa-B components RELA/p65 and NFKB1/p50 on ERE sequences. Can also act synergistically with NF-kappa-B to activate transcription involving respective recruitment adjacent response elements; the function involves CREBBP.
Can activate the transcriptional activity of TFF1. Also mediates membrane-initiated estrogen signaling involving various kinase cascades. Essential for MTA1-mediated transcriptional regulation of BRCA1 and BCAS3 .
PMID:17922032
Maintains neuronal survival in response to ischemic reperfusion injury when in the presence of circulating estradiol (17-beta-estradiol/E2) (By similarity)
Androgen receptor
binder
Specific functionandrogen binding
Cellular location
Nucleus
General function & pharmacology
Steroid hormone receptors are ligand-activated transcription factors that regulate eukaryotic gene expression and affect cellular proliferation and differentiation in target tissues .
PMID:19022849
Transcription factor activity is modulated by bound coactivator and corepressor proteins like ZBTB7A that recruits NCOR1 and NCOR2 to the androgen response elements/ARE on target genes, negatively regulating androgen receptor signaling and androgen-induced cell proliferation .
PMID:20812024
Transcription activation is also down-regulated by NR0B2. Activated, but not phosphorylated, by HIPK3 and ZIPK/DAPK3
PMID:19022849
Transcription factor activity is modulated by bound coactivator and corepressor proteins like ZBTB7A that recruits NCOR1 and NCOR2 to the androgen response elements/ARE on target genes, negatively regulating androgen receptor signaling and androgen-induced cell proliferation .
PMID:20812024
Transcription activation is also down-regulated by NR0B2. Activated, but not phosphorylated, by HIPK3 and ZIPK/DAPK3
Sex hormone-binding globulin
SHBG
inhibitor
binder
Specific functionandrogen binding
Cellular location
Secreted
General function & pharmacology
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, and 17-beta-estradiol.
Regulates the plasma metabolic clearance rate of steroid hormones by controlling their plasma concentration
Regulates the plasma metabolic clearance rate of steroid hormones by controlling their plasma concentration
Metabolizing enzymes(2)
Enzymes involved in drug metabolism — important for understanding drug interactions
Enzyme activity key
substrate
inhibitor
inducer
CYP3A5Cytochrome P450 3A5
substrate
CYP3A4Cytochrome P450 3A4
substrate
Scientific references(17)
Edgren R.A., Stanczyk F.Z.
Nomenclature of the gonane progestins.
Contraception
199960(6):313. doi: 10.1016/s0010-7824(99)00101-8
Sitruk-Ware R.
New progestagens for contraceptive use.
Human Reproduction Update
200612(2):169-178. doi: 10.1093/humupd/dmi046
Kahlenborn C., Peck R., Severs W.B.
Mechanism of action of levonorgestrel emergency contraception.
Linacre Q
2015 Feb82(1):18-33. doi: 10.1179/2050854914Y.0000000026
Kook K., Gabelnick H., Duncan G.
Pharmacokinetics of levonorgestrel 0.
75 mg tablets
Contraception. 200266(1):73-76. doi: 10.1016/s0010-7824(02)00321-9
Sambol N.C., Harper C.C., Kim L., Liu C.Y., Darney P., Raine T.R.
Pharmacokinetics of single-dose levonorgestrel in adolescents.
Contraception
2006 Aug74(2):104-9. doi: 10.1016/j.contraception.2006.01.011. Epub 2006 Jun 16
Natavio M., Stanczyk F.Z., Molins E.A.G., Nelson A., Jusko W.J.
Pharmacokinetics of the 1.
5 mg levonorgestrel emergency contraceptive in women with normal, obese and extremely obese body mass index
Contraception. 2019 May99(5):306-311. doi: 10.1016/j.contraception.2019.01.003. Epub 2019 Jan 28
Shohel M., Rahman M.M., Zaman A., Uddin M.M., Al-Amin M.M., Reza H.M.
A systematic review of effectiveness and safety of different regimens of levonorgestrel oral tablets for emergency contraception.
BMC Womens Health
2014 Apr 414:54. doi: 10.1186/1472-6874-14-54
Polis C.B., Phillips S.J., Hillier S.L., Achilles S.L.
Levonorgestrel in contraceptives and multipurpose prevention technologies: does this progestin increase HIV risk or interact with antiretrovirals? AIDS. 2016 Nov 13;30(17):2571-2576. doi: 10.
1097/QAD
0000000000001229
Raymond E.G., Coeytaux F., Gemzell-Danielsson K., Moore K., Trussell J., Winikoff B.
Embracing post-fertilisation methods of family planning: a call to action.
Journal Fam Plann Reprod Health Care
2013 Oct39(4):244-6. doi: 10.1136/jfprhc-2013-100702
Beatty M.N., Blumenthal P.D.
The levonorgestrel-releasing intrauterine system: Safety, efficacy, and patient acceptability.
Therapeutics Clinical Risk Manag
2009 Jun5(3):561-74. doi: 10.2147/tcrm.s5624. Epub 2009 Aug 3
Juchem M., Pollow K.
Binding of oral contraceptive progestogens to serum proteins and cytoplasmic receptor.
American Journal Obstetrics Gynecology
1990 Dec163(6 Pt 2):2171-83. doi: 10.1016/0002-9378(90)90559-p
Stanczyk F.Z., Roy S.
Metabolism of levonorgestrel, norethindrone, and structurally related contraceptive steroids.
Contraception
199042(1):67-96. doi: 10.1016/0010-7824(90)90093-b
Brinton L.A., Felix A.S.
Menopausal hormone therapy and risk of endometrial cancer.
Journal Steroid Biochemistry Molecular Biological
2014 Jul142:83-9. doi: 10.1016/j.jsbmb.2013.05.001. Epub 2013 May 13
Townsend S.
Fleming, Very Rev. Horace Townsend, (died 11 Dec. 1909). Who Was Who. 2007. doi: 10.1093/ww/9780199540884.
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UPA and LNG in emergency contraception: the information by EMA and the scientific evidences indicate a prevalent anti-implantation effect. Eur J Contracept Reprod Health Care. 2019 Jan 18:1-7. doi: 10.1080/13625187.
2018
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Gemzell-Danielsson K., Berger C., Lalitkumar P.G.
Mechanisms of action of oral emergency contraception.
Gynecology Endocrinol
2014 Oct30(10):685-7. doi: 10.3109/09513590.2014.950648. Epub 2014 Aug 12
Moreno I., Quinones L., Catalan J., Miranda C., Roco A., Sasso J., Tamayo E., Caceres D., Tchernitchin A.N., Gaete L., Saavedra I.
[Influence of CYP3A4/5 polymorphisms in the pharmacokinetics of levonorgestrel: a pilot study].
Biomedica
2012 Oct-Dec32(4):570-7. doi: 10.1590/S0120-41572012000400012
ATC classification(6 codes)
ATC G03AB03
ATC G03AD01
ATC G03AC03
ATC G03FB09
ATC G03AA07
ATC G03FA11
Affected organisms(1)
Humans and other mammals
International brands(10)
Experimental properties(6)
Commercial products(382)
Chemical identifiers
CAS, UNII, InChI Key and database cross-references
Show
Chemical identifiers
CAS, UNII, InChI Key and database cross-references
Linked compound data from DrugBank Open Data (CC BY-NC 4.0)
Levonorgestrel
Additional database identifiers
Drugs Product Database (DPD)
7490
ChemSpider
12560
BindingDB
50410522
PDB
NOG
Guide to Pharmacology
2881
ZINC
ZINC000003814395
HUGO Gene Nomenclature Committee (HGNC)
HGNC:8910
GenAtlas
PGR
GeneCards
PGR
GenBank Gene Database
X51730
GenBank Protein Database
35652
Guide to Pharmacology
627
UniProt Accession
PRGR_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:11284
GenAtlas
SRD5A1
GeneCards
SRD5A1
GenBank Gene Database
M32313
GenBank Protein Database
177767
UniProt Accession
S5A1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:3467
GenAtlas
ESR1
GeneCards
ESR1
GenBank Gene Database
X03635
GenBank Protein Database
31234
Guide to Pharmacology
620
UniProt Accession
ESR1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:644
GenAtlas
AR
GeneCards
AR
GenBank Gene Database
M20132
GenBank Protein Database
178628
Guide to Pharmacology
628
UniProt Accession
ANDR_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:10839
GenAtlas
SHBG
GeneCards
SHBG
GenBank Gene Database
X16349
GenBank Protein Database
296673
UniProt Accession
SHBG_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:7978
GenAtlas
NR3C1
GeneCards
NR3C1
GenBank Gene Database
X03225
GenBank Protein Database
31680
Guide to Pharmacology
625
UniProt Accession
GCR_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:2638
GenAtlas
CYP3A5
GeneCards
CYP3A5
GenBank Gene Database
J04813
GenBank Protein Database
181346
Guide to Pharmacology
1338
UniProt Accession
CP3A5_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:2637
GenAtlas
CYP3A4
GeneCards
CYP3A4
GenBank Gene Database
M18907
Guide to Pharmacology
1337
UniProt Accession
CP3A4_HUMAN
International reference pricing
15 formulations
Reference pricing from DrugBank. Prices are indicative and may not reflect current UK costs.
From $0.60/g
To $843.66/each
Acidophilus 10 bu/gm granules
$0.60/g
Trivora-28 tablet
$0.98/tablet
Levora-28 tablet
$1.10/tablet
Tri-levlen 28 tablet
$1.25/tablet
Levlen 28 tablet
$1.30/tablet
Source: DrugBank. Used under CC BY-NC 4.0 academic licence for non-commercial purposes.
Patent information
16 active patents, 16 expired
11571328
United States
Approved 7 Feb 2023 · Expires 7 Sept 2040
14y 5m
10028858
United States
Approved 24 Jul 2018 · Expires 22 Mar 2034
7y 11m
11090186
United States
Approved 17 Aug 2021 · Expires 24 Oct 2033
7y 6m
12004992
United States
Approved 11 Jun 2024 · Expires 6 Oct 2033
7y 6m
9668912
United States
Approved 6 Jun 2017 · Expires 1 Apr 2031
4y 12m
The earliest active patent expires February 2027. Generic versions may become available after this date.
Source: DrugBank · CC BY-NC 4.0. Patent data sourced from national patent offices. Expiry dates may not reflect extensions, regulatory exclusivity periods, or legal challenges.
DrugBank citations
If you use DrugBank data in your research, please cite the following publications:
Knox C., Wilson M., Klinger C.M., et al
DrugBank 6.
0: the DrugBank Knowledgebase for 2024
Nucleic Acids Res. 2024 Jan 552(D1):D1265-D1275
Wishart D.S., Feunang Y.D., Guo A.C., et al
DrugBank 5.
0: a major update to the DrugBank database for 2018
Nucleic Acids Res. 2017 Nov 846(D1):D1074-D1082
Show earlier publications
Law V., Knox C., Djoumbou Y., et al
DrugBank 4.
0: shedding new light on drug metabolism
Nucleic Acids Res. 2014 Jan 142(1):D1091-7
Knox C., Law V., Jewison T., et al
DrugBank 3.
0: a comprehensive resource for 'omics' research on drugs
Nucleic Acids Res. 2011 Jan39(Database issue):D1035-41
Wishart D.S., Knox C., Guo A.C., et al
DrugBank: a knowledgebase for drugs, drug actions and drug targets.
Nucleic Acids Research
2008 Jan36(Database issue):D901-6
Wishart D.S., Knox C., Guo A.C., et al
DrugBank: a comprehensive resource for in silico drug discovery and exploration.
Nucleic Acids Research
2006 Jan 134(Database issue):D668-72
Source: go.drugbank.comCC BY-NC 4.0
Updated 26 days ago(8 Mar 2026)