Norethisterone 5mg is a prescription-only medicine (POM) licensed in the UK for the postponement of menstruation. It is a progestogen, meaning it is a synthetic form of the female hormone progesterone, and it works by mimicking the role progesterone plays in the menstrual cycle to prevent the uterine lining from shedding. For women who have an important event, holiday, or other reason to delay their period, Norethisterone can be an effective and well-established option when assessed and supplied appropriately by a qualified healthcare professional.
At C&H Barton Pharmacy, we offer Norethisterone 5mg tablets for period delay following a clinical consultation. Our pharmacists will assess your suitability for the treatment, explain how to use it correctly, and ensure you have all the information you need before starting. You can book your consultation online or speak to us directly via live chat. If you are also interested in other women’s health services we offer, including period delay tablets, you can find more information on our dedicated service page.
Key Takeaways
✓ Norethisterone 5mg is a prescription-only medicine licensed in the UK for the postponement of menstruation.
✓ The usual licensed regimen is one 5mg tablet three times a day, starting three days before your expected period.
✓ Norethisterone is not a contraceptive and does not protect against pregnancy. Appropriate contraception should be used if pregnancy is possible.
✓ A clinical assessment is required before Norethisterone can be supplied, as it is not suitable for everyone.
✓ Your period will usually begin within around 3 days of stopping the tablets.
✓ C&H Barton Pharmacy can carry out the consultation and supply the treatment if it is clinically appropriate for you.
Understanding the Menstrual Cycle
Before exploring how Norethisterone works, it is helpful to understand the basics of the menstrual cycle. The menstrual cycle is the monthly process through which the female reproductive system prepares for the possibility of pregnancy. It is regulated primarily by the hormones oestrogen and progesterone, which are produced by the ovaries. The cycle is divided into four phases:
✓ Follicular phase — the ovary develops a follicle containing an egg
✓ Ovulatory phase — the egg is released from the follicle and travels down the fallopian tube
✓ Luteal phase — the empty follicle produces progesterone to prepare the uterus for a potential pregnancy
✓ Menstrual phase — if no pregnancy occurs, progesterone levels drop and the uterine lining is shed, causing a period
It is the fall in progesterone at the end of the luteal phase that triggers menstruation. Norethisterone works by artificially maintaining progesterone levels during this phase, preventing the uterine lining from shedding and thereby delaying the onset of a period.
How Does Norethisterone 5mg Work?
Norethisterone is a progestogen, meaning it is a synthetic compound that mimics the actions of natural progesterone in the body. For period delay, the UK-licensed regimen is one 5mg tablet taken three times a day, starting three days before your expected period. By maintaining elevated progesterone levels artificially, the uterus is prevented from shedding its lining, which delays the start of menstruation for as long as the tablets are taken.
Norethisterone works by binding to progesterone receptors in the body, triggering the same physiological responses as natural progesterone. It can also suppress the release of luteinising hormone (LH), which plays a role in triggering ovulation. Once you stop taking the tablets, your progesterone levels will fall and your period will usually begin within around three days.
It is important to be clear that Norethisterone used for period delay does not provide contraception and does not protect against pregnancy. If there is any possibility of pregnancy, appropriate contraception must be used alongside the tablets. Additionally, if your period does not occur after completing a course of Norethisterone, you should speak to a healthcare professional and pregnancy should be excluded before another course is taken.
Who Can Take Norethisterone for Period Delay?
Before Norethisterone can be supplied, a healthcare professional must assess whether it is clinically appropriate for you. This is not a medicine that is suitable for everyone, and a thorough consultation is an essential part of the process. Norethisterone may not be suitable if you have certain medical conditions or risk factors.
According to the UK Summary of Product Characteristics (SmPC), Norethisterone is contraindicated in the following circumstances:
✓ Pregnancy — Norethisterone must not be taken during pregnancy as it can harm the developing foetus
✓ Current or previous venous thromboembolism — including deep vein thrombosis (DVT) or pulmonary embolism
✓ Active or recent arterial thromboembolic disease — such as angina or myocardial infarction
✓ Liver function disturbance
✓ Idiopathic jaundice during a previous pregnancy
✓ Severe pruritus or pemphigoid gestationis during a previous pregnancy
✓ Undiagnosed irregular vaginal bleeding
✓ Porphyria
✓ Known hypersensitivity to Norethisterone or any of its excipients
In addition to these contraindications, the UK SmPC highlights that Norethisterone should be used with caution in women with conditions including migraine, epilepsy, asthma, cardiac dysfunction, and renal dysfunction. Risk factors for venous thromboembolism, such as a personal or family history of blood clots or severe obesity, should also be carefully considered during the assessment.
This is why a clinical assessment before supply is not simply a formality. It is an important safeguard to ensure that the treatment is appropriate and safe for you as an individual. Our pharmacists at C&H Barton will carry out a thorough consultation and will not supply the treatment if it is not clinically suitable for you.
How to Take Norethisterone 5mg for Period Delay
The UK-licensed regimen for period delay with Norethisterone 5mg is as follows:
✓ Dose: One 5mg tablet, three times a day
✓ When to start: Three days before your expected period
✓ Duration: Continue taking the tablets for as long as you need to delay your period. NHS Specialist Pharmacy Service guidance notes that Norethisterone can be used for up to 3 to 4 weeks if necessary, subject to clinical suitability being confirmed
✓ When your period will return: Your period will usually begin within approximately three days of stopping the tablets
The timing of when you start taking the tablets is particularly important. The UK-licensed regimen requires starting three days before the expected period, not on the day it is due. Starting too late may mean the tablets are not effective. Our pharmacist will explain the correct timing and provide full instructions during your consultation.
Always follow the instructions provided by your prescriber or pharmacist and read the current UK patient information leaflet, which you can download here.
What Are the Possible Side Effects of Norethisterone?
Like all medicines, Norethisterone may cause side effects in some women. The UK patient information leaflet provides a full list of possible adverse effects and should be read carefully before starting treatment. Common side effects that have been associated with Norethisterone include headaches, nausea, breast tenderness, and changes in mood. These are typically mild and resolve after stopping the tablets.
Treatment should be stopped and you should seek medical advice if you experience any of the following during your course:
✓ Jaundice or deterioration in liver function
✓ A significant increase in blood pressure
✓ A new onset of migraine-type headache
If you experience any concerning symptoms while taking Norethisterone, contact our pharmacy team or seek medical advice promptly. A full and current list of side effects, warnings, and drug interactions is available in the patient information leaflet for the specific product supplied to you. Always refer to the current leaflet rather than relying solely on online information, as product information can change.
Important Considerations Before Taking Norethisterone
There are several important points to keep in mind before taking Norethisterone for period delay:
✓ It is not a contraceptive. Norethisterone does not protect against pregnancy and should not be used as a method of contraception. If you require contraception, this should be arranged separately.
✓ Pregnancy must be excluded. If your period does not arrive within the expected timeframe after stopping treatment, you should exclude pregnancy before taking another course.
✓ It should not be used more often than necessary. The UK SmPC and prescribing guidance make clear that Norethisterone for period delay is intended for occasional use. It should not be taken routinely every month as a regular method of managing your cycle without proper clinical oversight.
✓ It is not suitable during pregnancy or breastfeeding. Norethisterone alters hormone levels and must not be taken if you are pregnant or breastfeeding.
✓ Always discuss with a healthcare professional. A consultation is required to ensure the treatment is appropriate for your specific circumstances, health history, and any medications you are taking.
Why Choose C&H Barton Pharmacy for Period Delay Treatment?
At C&H Barton Pharmacy, we take women’s health seriously. Our pharmacists are experienced in providing period delay consultations and take the time to ensure that every patient fully understands the treatment, its correct use, and any risks or considerations relevant to their individual circumstances. We do not supply Norethisterone without a proper assessment, and we will always signpost you to further support if the treatment is not appropriate for you.
Our service is convenient, confidential, and affordable. You can book your consultation online, speak to us in-store, or contact us via live chat. We also offer a range of other women’s health services including contraception, UTI treatment through the NHS Pharmacy First scheme, and blood testing for hormonal health. If you have questions about any of our services, our team is always happy to help.
Frequently Asked Questions
If you still have questions about Norethisterone 5mg for period delay, our most frequently asked questions are answered below.
Is Norethisterone available without a prescription?
No. Norethisterone 5mg is a prescription-only medicine (POM) in the UK. It cannot be purchased over the counter without a clinical assessment and a prescription from a qualified healthcare professional. At C&H Barton Pharmacy, our pharmacists can carry out the consultation and supply the treatment if it is clinically appropriate for you.
When exactly should I start taking Norethisterone?
According to the UK-licensed regimen, you should start taking Norethisterone three days before your expected period, not on the day it is due. Starting too late is a common reason for the tablets not working as intended. Our pharmacist will confirm the correct timing for you during your consultation based on your cycle.
Will Norethisterone stop my period completely?
Norethisterone delays the onset of your period for as long as you continue taking the tablets. Once you stop, your period will usually begin within approximately three days. It does not permanently suppress your menstrual cycle and your normal pattern should resume after the course is completed.
Can Norethisterone be used as a contraceptive?
No. Norethisterone used at the dose prescribed for period delay does not provide contraception and must not be relied upon to prevent pregnancy. If you require contraception, this should be discussed and arranged separately. Please speak to our pharmacist or your GP about suitable contraceptive options.
What should I do if my period does not return after stopping Norethisterone?
Your period should usually return within approximately three days of stopping Norethisterone. If it does not arrive within the expected timeframe, you should speak to a healthcare professional. As stated in the UK product information, pregnancy should be excluded before another course of Norethisterone is taken.
Period Delay Treatment at C&H Barton Pharmacy
Norethisterone 5mg is a well-established, UK-licensed medicine for the postponement of menstruation, but it is important that it is used correctly and only after a proper clinical assessment confirms it is suitable for you. At C&H Barton Pharmacy, our experienced pharmacists are here to guide you through the process, ensure you understand the treatment, and supply it safely and confidentially. If you would like to find out more or book your consultation, visit our period delay tablets page or book your appointment today.
☑ Clinically Reviewed by Pharmacy Mentor
A pharmacist reviews the content to help ensure medicines are presented responsibly and that patient-facing health information is accurate, appropriate, and aligned with current clinical guidance.
Last reviewed: 2 September 2026
Written on behalf of C&H Barton Pharmacy by Pharmacy Mentor.