Levonorgestrel

Generic Name: Levonorgestrel

Brand Names: Afirmelle 28 Day, Aftera, Alesse, Altavera 28 Day, Amethia 91 Day, Amethyst, Ashlyna 91 Day, Aubra 28 Day, Aviane 28, Ayuna 28 Day Pack, Balcoltra 28 Day, Bionafem, Camrese 91 Day, Camreselo 91 Day, Chateal 28 Day, Climara Pro, Curae, Daysee 91 Day, Delyla 28 Day, Dolishale 28 Day, Econtra, Enpresse 28 Day, Fallback Solo, Falmina 28 Day, Fayosim 91 Day, Her Style, Iclevia 91 Day, Indayo, Introvale 91 Day, Jaimiess 91 Day, Jolessa 91 Day, Joyeaux 28 Day, Kurvelo, Kyleena, Larissia 28 Day Pack, Levonest 28 Day, Levora 0.15/30 28 Day, Liletta, Lillow 28 Day, Lo Simpesse, LoJaimiess, Loseasonique, Lutera 28 Day, Marlissa 28 Day, Min-ovral, Mirena, Morning After, My Choice, My Way, Myzilra 28 Day, New Day, Next Choice, Next Choice One Dose, Opcicon One-step, Option 2, Orsythia 28 Day, Plan B, Plan B One-step, Portia 28 Day, Preventeza, Quartette 91 Day Pack, React, Rivelsa 91 Day, Seasonale, Seasonique, Setlakin 91 Day, Simpesse, Skyla, Sronyx 28 Day, Take Action, Triquilar, Trivora 28 Day, Twirla 3 Count Weekly Patch, Tyblume 28 Day, Vienva 28 Day

Drug Type: Small Molecule

Chemical Formula: C_₂₁H_₂₈O_₂

CAS Number: 797-63-7

Unique Ingredient Identifier: 5W7SIA7YZW

Background: Levonorgestrel (LNG) is a synthetic progestogen similar to Progesterone used in contraception and hormone therapy. 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. In addition to the above uses, levonorgestrel is used as a component of long-term combination contraceptives.

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.

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. 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. It has shown a lower efficacy when it is used off label within 96 hours.

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. It is used in various hormone-releasing intrauterine devices for long-term contraception ranging for a duration of 3-5 years. 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. A subdermal implant is also available for the prevention of pregnancy for up to 5 years.

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.Off-label, levonorgestrel may be used to treat menorrhagia, endometrial hyperplasia, and endometriosis.

Associated Conditions: Endometrial Hyperplasia, Endometriosis, Heavy Menstrual Bleeding, Hypermenorrhea, Postmenopausal Osteoporosis, Pregnancy, Moderate Menopausal Vasomotor Symptoms, Severe Vasomotor Symptoms Associated With Menopause