Drug/Small Molecule:

levonorgestrel

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. PubChem (source: Drug Bank)

For the treatment of menopausal and postmenopausal disorders and alone or in combination with other hormones as an oral contraceptive. (source: Drug Bank)

Binds to the progesterone and estrogen receptors. Target cells include the female reproductive tract, the mammary gland, the hypothalamus, and the pituitary. Once bound to the receptor, progestins like levonorgestrel will slow the frequency of release of gonadotropin releasing hormone (GnRH) from the hypothalamus and blunt the pre-ovulatory LH (luteinizing hormone) surge. (source: Drug Bank)

Levonorgestrel is a progestin or a synthetic form of the naturally occurring female sex hormone, progesterone. In a woman's normal menstrual cycle, an egg matures and is released from the ovaries (ovulation). The ovary then produces progesterone, preventing the release of further eggs and priming the lining of the womb for a possible pregnancy. If pregnancy occurs, progesterone levels in the body remain high, maintaining the womb lining. If pregnancy does not occur, progesterone levels in the body fall, resulting in a menstrual period. Levonorgestrel tricks the body processes into thinking that ovulation has already occurred, by maintaining high levels of the synthetic progesterone. This prevents the release of eggs from the ovaries. (source: Drug Bank)

Avoid alcohol.
Avoid excessive quantities of coffee or tea (Caffeine).
Increase dietary intake of magnesium, folate, vitamin B6, B12, and/or consider taking a multivitamin.
Take at the same time everyday.
Take with food. (source: Drug Bank)

Hepatic (source: Drug Bank)

55% (source: Drug Bank)

Levonorgestrel is not subjected to a "first-pass" effect and is virtually 100% bioavailable. (source: Drug Bank)

LD₅₀>5000 mg/kg (orally in rats) (source: Drug Bank)

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