1. What Norethisterone tablets are and what it they are used for
Norethisterone tablets belong to a group of medicines called progestogens. These work by acting on receptors in the body to mimic or exaggerate the effects of the natural hormone, progesterone.
Norethisterone tablets may be used to treat:
- or prevent abnormal or unexpected bleeding from the uterus
- the symptoms of pre-menstrual syndrome which occur before a period including breast pain, headache, migraine, water retention and mood disturbances
- painful or heavy periods
- certain types of breast cancer.
The tablets can also be used to stop periods.
2. Before you take
Your doctor will discuss your medical and family history with you. Your doctor will also need to check your blood pressure and make sure you are not pregnant. You may also need additional checks, such as a breast examination, that will be specific to your medical needs and/or concerns.
Do not take Norethisterone tablets and tell your doctor if you have:
allergic to norethisterone or any of the other ingredients. The ingredients are listed in section 6
pregnant or if you think you might be pregnant
or if you have:
- ever had a problem with your blood circulation. This includes a blood clot (thrombosis) in the legs (deep vein thrombosis), lungs (pulmonary embolism), heart (heart attack), brain (stroke) or any other parts of the body
- any symptoms of a blood clot, such as chest pain, unexplained and often sudden shortness of breath and/or cough
- any condition which makes you more at risk of a blood clot (thrombosis)
- ever suffered migraine with visual disturbance
- (or are recovering from) a liver disease and the blood tests show that your liver is not yet working normally
- (or have ever had) liver tumours.
diabetes with damaged blood vessels.
any type of cancer which might be made worse by exposure to female sex hormones (including breast cancer).
- problems with genital bleeding for which the cause is not yet known.
- a condition called endometrial hyperplasia which has not been treated.
In addition, do not take Norethisterone tablets if you have had any of the following conditions when you were pregnant:
- yellowing of the skin (idiopathic jaundice of pregnancy)
- itching of the whole body (pruritus of pregnancy)
Check with your doctor or pharmacist before taking Norethisterone tablets if you:
- have diabetes. Norethisterone tablets can produce changes in blood sugar levels. If you are diabetic, your doctor will check your blood sugar before starting treatment and regularly during treatment.
- are overweight (BMI≥30kg/m2)
- have high blood pressure
- have a heart valve disorder or a certain heart rhythm disorder (heart problems)
- have had a thrombosis/embolism or anyone in your close family has had a thrombosis, a heart attack or a stroke at a young age
- suffer from migraine, asthma, or kidney problems
- suffer from epilepsy (see “Other medicines and Norethisterone tablets”)
- have an inflammation of your veins (superficial phlebitis)
- have varicose veins
- have anyone in your immediate family who has had breast cancer
- have previously had a condition called chloasma where the skin on your face may develop brownish blotches. You may be advised to avoid exposure to the sun and to ultraviolet light while you are taking Norethisterone tablets.
- have previously suffered from depression.
- or someone in your close family has ever had high blood levels of cholesterol or triglycerides (fatty substances)
- have a disease of the liver or gall bladder
- have certain rare medical conditions such as systemic lupus erythematosus (SLE), sickle cell disease, Crohn’s disease or ulcerative colitis
- have haemolytic uremic syndrome (‘HUS)’
- have a condition that occurred for the first time or worsened during pregnancy or previous use of sex hormones (e.g. hearing loss, porphyria, or Sydenham's chorea)
- have hereditary angioedema. Consult your doctor immediately if you experience symptoms of angioedema such as swollen face, tongue or throat, and/or difficulty swallowing, or hives, together with difficulty breathing. Products containing oestrogens may induce or worsen symptoms of angioedema
- have an intolerance to some types of sugar (galactose intolerance, Lapp lactase deficiency or glucose-galactose malabsorption)
- are using other medications as mentioned in “Other Medicines & Norethisterone tablets”.
Tell your doctor before you take Norethisterone tablets if any of these applies to you. Also tell your doctor if any of these conditions develop or worsen while you are taking Norethisterone tablets, because you may need to stop taking it.
Norethisterone tablets and blood clots:
The main ingredient in Norethisterone (progestogen) is partly converted into oestrogen so you should also consider the general warnings given for combined oral contraceptive pills (“the Pill”).
Do not take Norethisterone tablets if you have a blood clot or have any medical condition which makes you more at risk of developing clots.
The risk of blood clots occurring in the veins and arteries is slightly greater in women who take the combined oral contraceptive pill than in women who don’t. People do not always fully recover from such blood clots, which can cause strokes, heart attacks and bleeding into the brain (subarachnoid haemorrhage). In very rare cases these blood clots can be fatal.
You are more at risk of having a blood clot:
- as you get older
- if you’re off your feet for a long time because of major surgery, injury or illness.
- if you smoke
- if you or any of your close family have had blood clots
- if you are overweight (BMI ≥ 30kg/m2)
- if you have a disorder of blood fat (lipid) metabolism
- if you have a blood disorder
- if you have high blood pressure
- if you suffer from migraines
- if you have a heart valve disorder or a particular type of irregular heartbeat (atrial fibrillation)
- if you have recently had a baby
- if you have diabetes
- if you have certain medical conditions such as systemic lupus erythematosus (SLE), sickle cell disease, Crohn’s disease or ulcerative colitis
Tell your doctor if any of these apply to you. Taking Norethisterone tablets may add to this risk so it may not be suitable for you.
To reduce the risk of blood clots, treatment with Norethisterone tablets must be stopped:
- six weeks before any planned major operation
- before any surgery to the legs
- before medical treatment for varicose veins
- if you are going to be immobilised for a long time (e.g. if you need bed-rest after an accident or operation, or if you have a plaster cast on a broken leg)
Signs of a blood clot include:
- a migraine for the first time or one that is worse than normal
- unusually frequent or severe headaches
- any sudden changes to your eyesight (such as loss of vision or blurred vision)
- any sudden changes to your hearing, speech, sense of smell, taste or touch
pain or swelling in your leg
stabbing pain when you breathe
coughing for no apparent reason
pain and tightness in the chest
- sudden weakness or numbness in one side or part of your body
dizziness or fainting.
See a doctor as soon as possible if you notice any possible signs of blood clot. Do not take any more Norethisterone tablets until your doctor says you can.
Norethisterone tablets and cancer
If you have breast cancer, or have had it in the past, you should not take combined oral contraceptives (the Pill). The Pill slightly increases your risk of breast cancer. This risk goes up the longer you’re on it, but returns to normal within about 10 years of stopping it. Because breast cancer is rare in women under the age of 40, the extra cases of breast cancer in current and recent Pill users is small. For example:
- Of 10,000 women who have never taken the Pill, about 16 will have breast cancer by the time they are 35 years old.
- Of 10,000 women who take the Pill for 5 years in their early twenties, about 17–18 will have breast cancer by the time they are 35 years old.
- Of 10,000 women who have never taken the Pill, about 100 will have breast cancer by the time they are 45 years old.
- Of 10,000 women who take the Pill for 5 years in their early thirties, about 110 will have breast cancer by the time they are 45 years old.
Your risk of breast cancer is higher if:
- you have a close relative (mother, sister or grandmother) who has had breast cancer
- you are overweight (BMI ≥ 30kg/m2)
See a doctor as soon as possible if you notice any changes in your breasts, such as dimpling of the skin, changes in the nipple or any lumps you can see or feel.
Very rarely, the Pill has been linked with some forms of liver cancer in women who take it for a long time. These may lead to bleeding in the abdomen.
Taking the Pill has also been linked to liver diseases, such as jaundice and non-cancerous liver tumours, but this is rare.
See a doctor as soon as possible if you get severe pain in your stomach that does not go away, or yellow skin or eyes (jaundice). You may need to stop taking Norethisterone tablets.
Taking other medicines
Please tell your doctor or pharmacist if you are taking or have recently taken any other medicines, including medicines obtained without a prescription. Especially:
- other hormonal products (oestrogens or progestogens)
- medicines used to treat epilepsy (e.g. phenobarbital, phenytoin, carbamazepine)
- medicines used to treat infections (e.g. rifampicin, nevirapine, tetracyclines, ampicillin, oxacillin, co-trimoxazole, ritonavir, nelfinavir)
- St John’s Wort (hypericum perforatum) (a herbal remedy)
- ciclosporin (to prevent transplant rejection)
- other medicines which can also cause fluid retention such as anti-inflammatory medicines (e.g. ibuprofen) or vasodilators
Pregnancy and breast-feeding
If you are pregnant, planning to become pregnant or are breast-feeding ask your doctor or pharmacist for advice before taking this medicine as you should not take these tablets.
Driving and using machines
Norethisterone tablets may make you feel dizzy, drowsy or affect your vision. Make sure you are not affected before you drive or operate machinery.
If you have been told you have an intolerance to some sugars, contact your doctor before taking this medicine, as it contains a type of sugar called lactose.
If you go to a different doctor than the one who has prescribed you this medicine, or go to the hospital, let them know that you are taking Norethisterone tablets as they may affect certain tests.
3. How to take
Always take Norethisterone tablets exactly as your doctor has told you. If you are not sure, check with your doctor or pharmacist.
Swallow the tablets with water.
This medicine should be taken for as long as your doctor tells you to. If you finish the course of Norethisterone tablets you will usually have a menstrual bleed 2-3 days after the last tablet. If you do not have a period you must make sure you are not pregnant before taking more.
Day one of the cycle is the first day of your period.
Abnormal bleeding – 1 tablet three times a day for 10 days. Bleeding usually stops within 1-3 days. A period usually starts 2-4 days after stopping treatment.
Prevention of abnormal bleeding – 1 tablet twice a day from the 19th - 26th day of the cycle.
Premenstrual syndrome - 2 to 3 tablets a day from the 19th - 26th day of the cycle. You will normally be treated for several months.
Stopping a period - 1 tablet three times a day starting three days before the expected beginning of the period. Your period should occur 2-3 days after you have stopped taking the medicine.
Painful periods - 1 tablet three times a day for 20 days starting on the 5th day of the cycle. You will usually be treated for 3-4 cycles.
Heavy periods - 1 tablet two to three times a day from the 19th - 26th day of the cycle.
Endometriosis - 2 tablets a day starting on the 5th day of your cycle. If you continue having small bleeds (“spotting”), the dosage may be increased to 4 to 5 tablets a day. Once bleeding has stopped the dosage may be reduced. You will usually be treated continuously for 4-6 months or longer.
Breast cancer - 8 tablets a day, the dosage may be increased to 12 tablets a day.
Elderly & Children - Not recommended.
If you take more than you should
If you (or someone else) swallow a lot of tablets at the same time, or you think a child may have swallowed any, contact your nearest hospital casualty department or tell your doctor immediately. Signs of an overdose include feeling or being sick, breast enlargement or vaginal bleeding.
If you forget to take the tablets
Do not take a double dose to make up for a forgotten dose. If you forget to take a dose take it as soon as you remember it and then take the next dose at the right time.
If you stop taking the tablets
Talk to your doctor before you stop taking the tablets and follow their advice.
5. How to store
Keep out of the reach and sight of children.
Do not store the tablets above 25°C and keep in the original packaging.
Do not use Norethisterone tablets after the expiry date stated on the label/carton/bottle. The expiry date refers to the last day of that month.
Medicines should not be disposed of via wastewater or household waste. Ask your pharmacist how to dispose of medicines no longer required. These measures will help to protect the environment.