Period Delay · Clinical Information
Norethisterone for Period Delay
Pharmacist-reviewed information on Norethisterone 5mg tablets — a UK licensed prescription-only progestogen used to delay menstruation for short-term occasions, following a clinical assessment.
UK Pharmacist Reviewed
UK Licensed
GPhC Registered Pharmacy
Medication
Prescription Only
Period Delay Treatment
UK Licensed
Norethisterone
norethisterone 5 mg
Progestogen
What it is
Norethisterone is a synthetic progestogen used for short-term period delay. It is a prescription-only medicine commonly prescribed to postpone menstruation when started before bleeding begins.
How it works
Norethisterone works in a similar way to the natural hormone progesterone. It helps maintain the lining of the womb and delays the normal shedding process that causes a period. Once the tablets are stopped, hormone levels fall and bleeding usually begins within a few days.
Effectiveness
Usually effective when started at least 3 days before your expected period. If treatment is started too late, or after bleeding has already begun, spotting or breakthrough bleeding may still occur.
Dosing
For period delay, the usual dose is one 5 mg tablet three times daily, starting 3 days before your period is due.
5 mg Morning
5 mg Afternoon
5 mg Evening
Take exactly as prescribed. Do not take extra tablets to make up for missed doses.
When to start
Start taking Norethisterone 3 days before your period is expected to begin. Continue taking it for the number of days advised by your prescriber. Your period will usually start within 2 to 3 days after stopping the tablets.
Who it is for
Adult women who want to delay their period for a short-term occasion such as travel, sport, religious commitments, weddings, holidays, or other planned events. It is best suited to women with a predictable menstrual cycle who can start treatment in advance.
Important advice
Norethisterone is not a contraceptive. It will not protect against pregnancy. If you do not want to become pregnant, you should use a suitable contraceptive method while taking it.
Side effects
- Headache, dizziness, or tiredness
- Spotting, breakthrough bleeding, or changes in bleeding pattern
- Breast tenderness, bloating, or fluid retention
- Feeling sick, stomach discomfort, or changes in appetite
- Mood changes, reduced sex drive, or difficulty sleeping
Not suitable if
You are pregnant or think you may be pregnant, have unexplained vaginal bleeding, have ever had a blood clot, have a close family history of blood clots, have current or previous serious heart disease, have liver disease, or have been advised not to use hormonal medicines.
Seek urgent help
Seek urgent medical attention if you develop chest pain, sudden shortness of breath, coughing blood, one-sided leg swelling or calf pain, sudden vision changes, severe unusual headache, difficulty speaking, weakness or numbness, or yellowing of the skin or eyes.
Norethisterone Clinical Summary
| Clinical Detail | Patient Guidance | Important Notes | |
|---|---|---|---|
| Medication | Norethisterone | Used to delay a period short-term | Prescription Only |
| Drug class | Progestogen | Synthetic progesterone-like hormone | Helps maintain the womb lining |
| Strength | 5 mg tablet | Usually taken three times daily | Total daily dose is commonly 15 mg |
| When to start | 3 days before expected period | Start before bleeding begins | Starting late may reduce effectiveness |
| Standard dose | One 5 mg tablet | Three times daily | Take as prescribed |
| Period return | Usually within 2 – 3 days | After stopping treatment | Seek advice if bleeding does not return |
| Contraception | Not a contraceptive | Use contraception if pregnancy is possible | Does not prevent pregnancy |
| Common side effects | Headache, dizziness, spotting | Breast tenderness, bloating, nausea | Side effects vary between patients |
| Key cautions | Pregnancy, blood clots, liver disease | Unexplained bleeding needs assessment | Clinical screening required |
| UK licensed | Yes | Licensed for postponement of menstruation | Prescription-only medicine |
Clinical Disclaimer
This page is for informational purposes only and does not constitute medical advice. All prescriptions should be issued only after a clinical assessment by a UK-registered pharmacist prescriber or other appropriate prescriber. Norethisterone is not suitable for everyone — particularly those who are pregnant, have unexplained vaginal bleeding, have a history of thrombosis, or have liver disease. Norethisterone is not a contraceptive. Always read the patient information leaflet supplied with the medicine. If you develop chest pain, shortness of breath, one-sided leg swelling, sudden visual or speech changes, severe unusual headache, or yellowing of the skin or eyes, seek urgent medical attention.
