Levonorgestrel
From DrugPedia: A Wikipedia for Drug discovery
Levonorgestrel Pubchem(13109)
A synthetic progestational hormone with actions similar to those of PROGESTERONE and about twice as potent as its racemic or (+-)-isomer (NORGESTREL). It is used for contraception, control of menstrual disorders, and treatment of endometriosis.
KEGG(C08149,C08153,D00950,D00954)
Activity Progestin
| Physical Property | Value | Units | Temp (deg C) | Source |
|---|---|---|---|---|
| Melting Point | 240 | deg C | EXP | |
| Water Solubility | 2.050 | mg/L | 25 | EST |
| Vapor Pressure | 3.93E-10 | mm Hg | 25 | EST |
| Henry's Law Constant | 7.70E-10 | atm-m3/mole | 25 | EST |
| Atmospheric OH Rate Constant | 1.14E-11 | cm3/molecule-sec | 25 | EST |
Contents |
[edit] Chemistry
Chemically, it is a hormonally active levorotatory enantiomer of the racemic mixture norgestrel. It is a gonane progestin derived from 19-nortestosterone.<ref>Edgren RA, Stanczyk FZ (1999). "Nomenclature of the gonane progestins". Contraception 60 (6): 313. doi:. PMID 10715364.</ref>
Its in vitro relative binding affinities at human steroid hormone receptors are: 323% that of progesterone at the progesterone receptor, 58% that of testosterone at the androgen receptor, 17% that of aldosterone at the mineralocorticoid receptor, 7.5% that of cortisol at the glucocorticoid receptor, and <0.02% that of estradiol at the estrogen receptor.<ref>Sitruk-Ware R (2006). "New progestagens for contraceptive use". Hum Reprod Update 12 (2): 169–78. doi:. PMID 16291771.</ref>
[edit] Usage
[edit] Oral contraceptives
At low doses, levonorgestrel is used in monophasic and triphasic formulations of combined oral contraceptive pills, with available monophasic doses ranging from 100-250 µg, and triphasic doses of 50 µg/75 µg/125 µg.
At very low daily dose of 30 µg, levonorgestrel is used in some progestogen only pill formulations.
[edit] Emergency contraception
Levonorgestrel is used in emergency contraceptive pills (ECPs), both in a combined Yuzpe regimen which includes estrogen, and as a levonorgestrel-only method. The levonorgestrel-only method uses levonorgestrel 1500 μg (as a single dose or as two 750 μg doses 12 hours apart) taken within 3 days of unprotected sex. There are many brand names of levonorgestrel-only ECPs, including: Escapelle, Plan B, Levonelle, NorLevo, Postinor-2, and 72-HOURS.<ref name="ecp worldwide">Template:Cite web</ref>
[edit] IUD
Levonorgestrel is the active ingredient in Mirena.
[edit] Contraceptive implants
Levonorgestrel is the active ingredient in Norplant and Jadelle.
[edit] References
[edit] External links
- Levonelle manufacturer's product information from Schering
- Monograph for levonorgestrel - Uk Medicines Information
