How to Take Norethisterone: Step-by-Step Schedule
How to take norethisterone 5mg for period delay: when to start, how to space your doses, what to do if you miss one, travelling across time zones, and when your period returns.
Part of the Period Delay Health Guide.
When to get urgent help: Call 999 or go to A&E if you have signs of a blood clot or stroke while taking norethisterone: pain, swelling or redness in one leg; sudden chest pain or breathlessness; coughing up blood; sudden weakness or numbness on one side of the body, difficulty speaking or a sudden severe headache. Also call 999 for a severe allergic reaction, such as swelling of the face, lips, tongue or throat, wheezing or difficulty breathing. Stop taking it and see a doctor the same day if your skin or eyes turn yellow, you get a migraine for the first time, or you have sudden changes to your vision.
Key fact: take one 5mg tablet three times a day, roughly 8 hours apart, starting at least 3 days before your period is due. Keep taking it until you want your period to come — it usually starts within 3 days of your last tablet.
Get Norethisterone 5mg Online
Prescribed after an online consultation with our GPhC-registered pharmacist independent prescribers, and dispensed from our UK pharmacy in plain packaging.
Get norethisterone 5mg →This guide is for people who have been prescribed norethisterone and want to know exactly how to take it. To find out whether it suits you, see how norethisterone works. For timing around a trip, see period delay for a holiday or event.
Basic schedule
| Detail | Instruction |
|---|---|
| Dose | One 5mg tablet |
| How often | Three times a day |
| Spacing | Roughly every 8 hours, for example 7am, 3pm and 11pm |
| When to start | At least 3 days before your period is due |
| How long | As long as your prescriber advises (the Primolut N licence describes no longer than 10–14 days; NHS guidance allows up to 3–4 weeks if necessary) |
| When your period comes | Usually within 3 days of your last tablet |
Step by step
1
Work out your start day
Count back at least 3 days from the day your period is due. If your cycle is irregular, start a little earlier, as your prescriber advises.
2
Take your first tablet
Take it with water at your chosen time and set phone reminders for the next two doses.
3
Keep to three doses a day
Consistency matters more than exact times. If 7am, 3pm and 11pm doesn’t suit you, pick another routine about 8 hours apart and stick with it.
4
Travelling across time zones
Keep your doses roughly 8 hours apart and move to local times gradually. Carry your tablets in your hand luggage in their original pack. On long flights, keep hydrated and walk around regularly.
5
Stop when you want your period
Take your last tablet when you are ready for your period. It usually starts within 3 days. If it doesn’t, take a pregnancy test and speak to your GP or our pharmacist before taking another course.
How many tablets you need
At three tablets a day, a pack of 30 tablets lasts 10 days. Count the days from your start day (3 days before your period is due) to the day you want your period to start, multiply by three, and your prescriber will confirm the quantity during your consultation.
If you miss a dose
The patient leaflet says to take the missed tablet as soon as you remember, then carry on taking your tablets at the normal times. Do not take a double dose to make up for a forgotten one.
Missed several doses? Spotting or bleeding becomes more likely if levels drop. Carry on as normal and contact your prescriber or pharmacist for advice.
What to expect
| When | What usually happens |
|---|---|
| First few days | Some people notice nausea, headache or breast tenderness at first |
| While taking it | Your period stays delayed. Spotting can happen and does not usually mean it has stopped working |
| After your last tablet | Your period usually starts within 3 days. It may be heavier or longer than usual |
| Following months | If your periods do not return to your usual pattern, speak to your GP |
For what side effects to look out for and when to contact your prescriber, see norethisterone side effects: what to expect.
UK safety and prescribing information
- Legal status: norethisterone is a prescription-only medicine (POM). At Access Doctor it is prescribed only after an online consultation with a GPhC-registered pharmacist independent prescriber, who may decline and suggest an alternative or that you see your GP.
- Licence: it is the only progestogen licensed in the UK to delay periods (NHS Specialist Pharmacy Service). The dose is 5mg three times a day, starting 3 days before your period is due.
- Course length: take it for as long as your prescriber advises. The Primolut N licence describes courses of no longer than 10 to 14 days, and NHS Specialist Pharmacy Service guidance says it can be taken for up to 3 to 4 weeks if necessary.
- Not a contraceptive: use condoms or another method while you take it.
- Blood clots: part of each dose is converted in the body to ethinylestradiol, the oestrogen in the combined pill (about 4–6 micrograms for every 1mg, according to the Primolut N product information), so the same blood clot warnings apply. Your prescriber will check risk factors such as a previous clot, smoking, a BMI over 30, being over 35, recent surgery and long-haul travel.
- Pregnancy and breastfeeding: do not take it if you are or might be pregnant. The Primolut N product information says it should be avoided while breastfeeding, so ask your prescriber.
- Reporting side effects: you can report suspected side effects to the MHRA through the Yellow Card scheme website or the Yellow Card app.
Planning to Delay Your Period?
Start your consultation at least a week before your period is due, so your tablets arrive in time to begin 3 days beforehand. Approved orders placed before 3pm Monday to Friday are dispatched that day by Royal Mail Tracked 24.
Get norethisterone 5mg →Frequently asked questions
When should I take my norethisterone tablets?
Take one 5mg tablet three times a day, roughly 8 hours apart, for example at 7am, 3pm and 11pm. Start at least 3 days before your period is due.
What if I forget a dose of norethisterone?
Take the missed tablet as soon as you remember, then carry on at your normal times. Do not take a double dose. Missing doses makes spotting or bleeding more likely.
Can I take norethisterone with food?
The leaflet does not say it must be taken with or without food. If it makes you feel sick, taking it with a snack or meal may help. Ask your pharmacist if you are unsure.
How do I know norethisterone is working?
If your period has not started by its usual date, it is working. Spotting can happen and does not usually mean it has stopped working. Contact your prescriber if you get heavy bleeding.
What happens when I stop taking norethisterone?
Your period usually starts within 3 days of your last tablet and may be heavier or longer than usual. If it does not start, take a pregnancy test and speak to your GP or pharmacist.
Can I stop norethisterone early if I don't need the full delay?
Yes. You can stop whenever you are ready for your period, and it usually starts within 3 days. Tell your prescriber if you are stopping because of side effects.
References
- electronic Medicines Compendium. Norethisterone 5mg Tablets — Summary of Product Characteristics and Patient Information Leaflet. medicines.org.uk
- electronic Medicines Compendium. Primolut N 5mg Tablets — Summary of Product Characteristics. medicines.org.uk
- NHS Specialist Pharmacy Service. Choosing a medicine to delay periods. 2025. sps.nhs.uk
- NHS. Norethisterone. nhs.uk
- MHRA. Yellow Card scheme. yellowcard.mhra.gov.uk
Medical disclaimer: This article is for information only and does not replace advice from your GP, pharmacist or prescriber. Norethisterone is a prescription-only medicine; always follow the instructions on your label and leaflet. In a medical emergency, call 999.