Indications
Norgestrel is a man-made progestogen (a female hormone). It is used to prevent pregnancy, either on its own as a progestogen-only pill or, more often, combined with an oestrogen such as Ethinylestradiol in a combined oral contraceptive pill. Combined pills may also be used to regulate periods and ease painful or heavy periods.
How It Works
Norgestrel thickens the mucus at the neck of the womb so sperm cannot pass easily, and changes the womb lining so a fertilised egg is less likely to settle. In combined pills, and sometimes on its own, it also stops the ovaries from releasing an egg each month.
Dosage and Administration
Take one tablet by mouth every day at the same time, following the order and pill-free or inactive-tablet days shown on the strip, as directed on the pack or by your doctor. Progestogen-only pills must be taken within the same 3 hours each day with no break. If you miss a pill, have vomiting within 3 to 4 hours, or severe diarrhoea, follow the missed-pill advice on the leaflet and use condoms until protection returns.
Interactions
Rifampicin, Carbamazepine, Phenytoin, Phenobarbital, Topiramate, some HIV medicines and St John’s Wort can make the pill fail; use extra or other contraception. Pills containing oestrogen may reduce Lamotrigine levels. Tell your doctor about all medicines you use.
Contraindications
- Known or suspected pregnancy
- Unexplained vaginal bleeding
- Current or past breast cancer
- Serious liver disease or liver tumour
- For combined pills: past blood clot, stroke or heart attack; migraine with aura; smoking at age 35 or over; uncontrolled high blood pressure; diabetes with blood vessel damage
Side Effects
Common effects include irregular bleeding or spotting, headache, breast tenderness, nausea, mood changes, acne and changes in weight. These often settle after the first few months.
Get urgent medical help for pain or swelling in one leg, sudden chest pain or breathlessness, a sudden severe headache, weakness or numbness on one side, sudden vision or speech problems, yellow skin or eyes, or severe tummy pain (which may rarely mean a pregnancy outside the womb).
Pregnancy and Lactation
Do not use if you are pregnant; stop and see a doctor if you think you may be pregnant. Progestogen-only pills are generally suitable while breastfeeding. Combined pills may reduce milk supply and are usually avoided in the first weeks after birth; ask your doctor.
Precautions and Warnings
Have your blood pressure checked regularly. Tell your doctor about migraine, diabetes, high cholesterol, depression, gallbladder disease or a family history of blood clots. Stop combined pills before major surgery or long immobility as advised. The pill does not protect against sexually transmitted infections.
Overdose
Taking several pills at once usually causes only nausea, vomiting or some vaginal bleeding. Seek medical advice if a child swallows tablets.
Therapeutic Class
Progestogen; hormonal contraceptive
Storage
Store below 30°C in a dry place, away from light and out of the reach of children. Keep tablets in the original strip.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.