Primolut N: Uses, How It Works, Side Effects

What is Primolut N used for?

Primolut N is a prescription medicine. On a doctor's advice it is used for the following period-related problems.

• Abnormal bleeding from the womb (dysfunctional uterine bleeding) and heavy periods (menorrhagia)
• Painful periods (dysmenorrhoea) and premenstrual syndrome
• Endometriosis
• Postponing a period, in people who are not at risk of pregnancy during treatment

How does Primolut N work?

Norethisterone is a progestogen, a medicine that acts like the hormone progesterone. It keeps the womb lining steady so it does not shed while the tablets are taken, and bleeding follows when they stop.

What happens in your body after you take it

1. You swallow the tablet

   The tablet is swallowed whole with some liquid. It dissolves in the gut and norethisterone is absorbed into the blood.

2. It travels in the blood

   Norethisterone is carried around the body and reaches the womb lining and other tissues that respond to progesterone.

3. It attaches to progesterone receptors

   It binds to progesterone receptors in the womb lining and acts much like natural progesterone.

4. The womb lining is held steady

   The lining stops shedding while the tablets are taken, which helps with heavy or abnormal bleeding, or delays a period.

5. The body clears it

   The liver breaks the medicine down. When the course ends the lining sheds, and bleeding usually follows within a few days.

How to take Primolut N

Take Primolut N exactly as your doctor has prescribed or as printed on the pack. The number of tablets and the days they are taken depend on the reason it was prescribed.

• Swallow the tablets whole with some liquid.
• To postpone a period, doctors start the tablets a few days before the expected period; follow the doctor's instructions on timing.
• If you miss a dose, take it when you remember. If it is almost time for the next dose, skip the missed one. Do not take two doses together.
• It does not give contraceptive cover when used for period problems or postponement. Ask your doctor about contraception.
• Tell your doctor if bleeding is unusually heavy or no period comes after the course.

Side effects of Primolut N

Many people take norethisterone without serious problems. Some effects are common, but a few need medical help.

Uncommon or mild

• Spotting or bleeding between periods, or lighter periods
• Headache
• Nausea
• Swelling of hands or feet from fluid retention
• Absent periods when taken for endometriosis

Who should be careful

Norethisterone is partly changed into oestrogen in the body, so some cautions for combined contraceptive pills also apply. Tell your doctor your full history.

• Do not take it in pregnancy or if you may be pregnant, or while breastfeeding
• Do not take it if you have, or have had, blood clots in a vein or artery, or migraine with warning symptoms
• Severe liver disease or a liver tumour, breast cancer or another hormone-dependent cancer, and unexplained vaginal bleeding are reasons not to take it
• Smoking, being overweight, a family history of clots and long periods of immobility add to clot risk; the UK label advises stopping about six weeks before planned surgery
• Diabetes: blood sugar may need more checks
• Epilepsy, migraine, asthma, heart or kidney problems: fluid retention can make these worse
• Dark patches on the face can appear; limit strong sun and UV exposure
• If a period does not arrive after a course, pregnancy must be ruled out

Medicines and things that interact with Primolut N

Some medicines can change how Primolut N works. Tell your doctor or pharmacist about everything you take, including herbal remedies.

• Medicines for epilepsy such as phenytoin, carbamazepine and primidone, and barbiturates: may make it work less well
• Rifampicin (tuberculosis) and HIV medicines such as ritonavir, nevirapine and efavirenz: may make it work less well
• St John's wort: may make it work less well
• Azole antifungals, macrolide antibiotics, verapamil, diltiazem and grapefruit juice: may raise its level
• Ciclosporin and lamotrigine: their levels may be changed

If someone takes too much

Storage

Store below 30 C in a dry place, protected from light and moisture, in the original strip, and out of the reach of children. Do not use after the expiry date. Check the pack for the exact storage instructions.

Regulatory status in India

Approved for sale in India as a prescription medicine. Single-ingredient norethisterone is not on the CDSCO list of medicines banned under section 26A of the Drugs and Cosmetics Act. Primolut N contains norethisterone only.

Other brands with the same medicine

Norethisterone 5 mg tablets are sold under other brand names. They contain the same medicine; check the label for the strength. Some products with a similar name contain other medicines, so do not switch between them without asking your doctor.

Other strengths and forms

Norethisterone is sold in other strengths and in combination with oestrogen in contraceptive pills. The strength and contents are printed on the pack and are not the same across products, so check the label of the one you have.

Common questions