Norgestrel
Indications
Norgestrel tablets are indicated for use by females of reproductive potential to prevent pregnancy. This tablet are not for use as emergency contraception.
Pharmacology
Progestin-only oral contraceptives such as Norgestrel tablets prevent conception by suppres sing ovulation in approximately half of the cycles in users, thickening the cervical mucus to inhibit sperm penetration, lowering the midcycle LH and FSH peaks, slowing the movement of the ovum through the fallopian tubes, and altering the endometrium. Serum progestin levels peak about two hours after oral administration, followed by rapid distribution and elimination. By 24 hours after drug ingestion, serum levels are near baseline, making efficacy dependent upon rigid adherence to the dosing schedule. There are large variations in serum levels among individual users. Progestin-only administration results in lower steady-state progestin levels and a shorter elimination half-life than concomitant administration with estrogens.
Dosage And Administration
To achieve maximum contraceptive effectiveness, Norgestrel Tablets must be taken exactly as directed. The woman should take one tablet every day, at the same time. The administration is continuous, with no interruption between pill packs.
Contraindications
Norgestrel tablet is contraindicated for use by women who are known to have the following conditions:
- Known or suspected pregnancy
- Known or suspected carcinoma of the breast, or other progestin-sensitive cancer, now or in the past
- Undiagnosed abnormal uterine bleeding
- Hypersensitivity to any component of this product
- Benign or malignant liver tumors
Side Effects
An increased risk of the following adverse reactions has been reported with the use of progestin-only oral contraceptives: Delayed follicular atresia/ovarian cysts, Menstrual irregularity, changes in menstrual flow; breakthrough bleeding/spotting; amenorrhea, prolonged bleeding. The following adverse reactions were reported in ≥5% of subjects in the Norgestrel Tablet clinical studies:
- Headache
- Dizziness
- Nausea
- Increased appetite
- Abdominal pain, cramps and bloating
- Fatigue
- Vaginal discharge
- Dysmenorrhea
- Nervousness
- Backache
- Breast discomfort
- Acne
Pregnancy And Lactation
Pregnancy: Norgestrel Tablets are contraindicated for use in pregnant women because there is no need for pregnancy prevention in a woman who is already pregnant. Published studies report no harmful effects on fetal development associated with long-term use of contraceptive doses of oral progestins in pregnant women. Discontinue Norgestrel Tablets if pregnancy is confirmed.
Nursing Mothers: Small amounts of progestin pass into the breast milk, resulting in steroid levels in infant plasma. No adverse effects have been reported on breastfeeding performance or infant health. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for Norgestrel Tablets and any potential adverse effects on the breastfed infant from Norgestrel Tablets or from the underlying maternal condition.
Precautions And Warnings
Migraine/Headache: The onset or exacerbation of migraine, or development of headache with a new pattern that is recurrent, persistent, or severe requires evaluation of the cause because women with migraine may be at increased risk of stroke.
Drug Interactions:
- The effectiveness of progestin-only pills is reduced by hepatic enzyme-inducing drugs such as phenytoin, carbamazepine, barbiturates, rifampin, efavirenz, bosentan and herbal preparations containing St. John’s Wort (hypericum perforatum ). This could result in unintended pregnancy or breakthrough bleeding. During concomitant use of Norgestrel and substances that may affect its efficacy, it is recommended that a nonhormonal back-up method of contraception (such as condom) be used in addition to the regular intake of Norgestrel Tablets. Use of a nonhormonal back-up method is recommeded for 28 days after discontinuation of substances that have led to induction of hepatic microsomal enzymes. For women receiving long-term therapy with hepatic enzyme inducers, another method of contraception should be considered.
- Effectiveness of progestin-containing hormonal contraceptives and emergency contraceptive ulipristal acetate may be decreased if progestin-containing hormonal contraceptives are used within five days after ulipristal acetate dosing. If a woman wishes to use Norgestrel Tablets after using ulipristal acetate, she should do so no sooner than 5 days after the intake of ulipristal acetate and she should use a reliable barrier method for subsequent acts of intercourse until her next menstrual period.
Gastrointestinal: Diarrhea and/or vomiting within 4 hours after taking a pill may reduce hormone absorption. Women should use of a nonhormonal back-up method of birth control (such as a condom or spermicide) during the next 48 hours.
Interactions with Laboratory Tests: The following endocrine tests may be affected by Norgestrel Tablets use:
- Sex hormone-binding globulin (SHBG) concentrations may be decreased.
- Total thyroxine concentrations may be decreased, due to a decrease in thyroid binding globulin (TBG). However, free thyroxine level should remain unchanged.
Overdose Effects
Symptoms of oral contraceptive overdosage may include nausea, vomiting, breast tenderness, dizziness, somnolence ( drowsiness/fatigue), and withdrawal bleeding in females. There is no specific antidote and further treatment of overdose, if necessary, is directed to the symptoms.
Therapeutic Class
Oral Contraceptive preparations
Use in special populations
Pediatric Use: The safety and efficacy of Norgestrel tablets have been established in women of reproductive age, including adolescents as young as 15 years of age, and almost 30% of subjects in the clinical trials who were under 20 years of age. Use of this product before menarche is not indicated.
Geriatric Use: Norgestrel tablet Tablets have not been studied in postmenopausal women and is not indicated in this population.
Storage Conditions
Store at controlled room temperature between 20° to 25°C.