• Norethisterone is a synthetic version of progesterone
• The most common reason for using norethisterone is to delay your period
• Norethisterone can delay a period for up to 17 days
• It can also be used to control or regulate the menstrual cycle, as well as treating endometriosis and premenstrual tension (PMT)
• You should use a non-hormonal form of contraception when taking norethisterone, such as condoms
• It is important to read the patient leaflet for a full list of side effects and cautions.

Norethisterone is a synthetic form of progesterone that works by mimicking the natural progesterone a woman makes during the menstrual cycle. When you take norethisterone, you keep the levels of progesterone in the body higher for longer than usual. 

High levels of progesterone make the body think that you have become pregnant. The body therefore maintains the thick uterine (womb) lining, and does not begin to shed it. This means that whilst taking norethisterone, your period will not start.  

When you stop taking norethisterone, the levels of progesterone in the body fall. The body begins to shed the lining of the uterus and a period occurs.

Women may choose to take norethisterone to occasionally delay menstruation for a variety of reasons. These might include:

• Travel or holidays
• Sporting events
• Operations
• Religious events.

Norethisterone is not a contraceptive, and so you must use a non-hormonal form of contraception such as condoms if you are sexually active.

Each norethisterone tablet should be swallowed with some water. The tablets can be taken with or without food. 1 tablet of norethisterone is taken 3 times a day.

To delay menstrual bleeding, you should start taking norethisterone 3 days before your period is due to start. 

Continue taking 1 tablet 3 times a day for no longer than 10 to 14 days. 

On stopping norethisterone, your period is likely to start within 2 to 3 days.

Each tablet contains 5 milligrams of norethisterone. One tablet should be taken 3 times a day for up to 14 days.

Like all medications, norethisterone can have some side effects. The most common side effects include:

• Nausea (feeling sick)
• Tender breasts
• Tiredness
• Feeling bloated
• A reduced sex drive
• Headache.

These side effects are likely to settle down, but if they persist or become troublesome you should speak to your doctor for further advice.

Occasionally it can worsen some chronic conditions, including:

• Migraine
• High blood pressure
• Depression.

Your prescriber will discuss the risks with you as part of your Consultation.

More serious side effects include:

• Blood clots to the legs or lungs
• Yellowing of the skin or whites of the eyes due to liver problems
• Weakness on one side of the body.

If any of these occur, you should speak to a doctor immediately.

Serious allergic reactions happen very rarely. If you have a severe allergic reaction (anaphylaxis) including breathlessness, lip swelling or tongue swelling, call 999 immediately.

Norethisterone may not be suitable for everyone. You should tell your prescriber if you:

• Are breastfeeding
• Are pregnant, or could have become pregnant just before starting norethisterone
• Have unexplained or irregular vaginal bleeding
• Have a history of cervical or breast cancer (unless norethisterone is being used to treat breast cancer)
• Have ever had a blood clot to the legs or lungs
• Have recently had angina, a heart attack or stroke caused by a blood clot
• Have liver problems
• Have porphyria.

Your prescriber can then advise whether norethisterone is a suitable medication for you.

Some medications can interact with norethisterone. You may be advised that norethisterone will not suit you if you already take:

• Medications for epilepsy
• Antibiotics or antiretroviral medications
• St John’s Wort (hypericum perforatum), a herbal remedy
• Aminoglutethimide
• Cyclosporin
• NSAIDs
• Medications that cause the blood vessels to dilate.

Because norethisterone may not suit everyone, we will complete a Consultation with you including a health questionnaire. This will ensure that the medication will be suitable for you.

A qualified prescriber will review your current medications, including any herbal remedies or supplements, to ensure that norethisterone will not interact with them. 

Once prescribed, norethisterone will be ordered on your behalf via electronic prescription. Norethisterone will then be conveniently dispatched from one of our partner pharmacies.

Can I buy Norethisterone online?

You can safely buy Norethisterone online at EU Meds. You will first need to have an online consultation with a pharmacist independent prescriber before your order will be supplied. The online consultation will ensure that Norethisterone is the right medication for your medical condition.

Do I need a prescription for Norethisterone?

Yes, in order to purchase Norethisterone you will need a valid prescription. Please note, all requests for supply of prescription medications are subject to an online clinical consultation and the decision to prescribe will be made by a doctor.