Skip to content
ClinCalc Pro
Menu
Calculators Drugs Pathways AI Dx Donate Get the App
Progestogen-Only Contraceptive (Oral) Pregnancy: SPC section 4.6: Pregnancy - Noriday is not indicated during pregnancy. If pregnancy occurs during medication with Noriday, treatment should be withdrawn immediately. Like all norethisterone derivatives used for contraception, Noriday has slight androgenic activity. At doses higher than normally used in OC and HRT formulations, masculinisation of female foetuses has been observed. The results of most epidemiological studies to date relevant to inadvertent foetal exposure to combinations of oestrogens with progestogens, indicate no teratogenic or foetotoxic effects. Breast-feeding - There is no evidence that Noriday tablets diminish the yield of breast milk. Small amounts of steroid materials appear in the milk; their effect on the breast-fed child has not been determined.

Progestogen-Only Pill (POP / Mini-pill)

Brand names: Noriday (norethisterone), Micronor, Cerazette (desogestrel), Cerelle, Norgeston (levonorgestrel)

The progestogen-only pill is an oral contraceptive containing a progestogen alone, providing an option for those who cannot or prefer not to use oestrogen-containing contraception.

Adult dose

Dose: Noriday 350 microgram tablets (norethisterone 350 micrograms per tablet) ONLY - oral contraception: one pill (350 micrograms norethisterone) every day, starting on the first day of menstruation, without a break in medication for as long as contraception is required. Additional contraceptive precautions (such as a condom) should be taken for the first 7 days of the first pack.
Route: Oral
Frequency: Once daily, continuously with no break (no pill-free interval), at the same time each day.
SCOPE: this card is for ONE product only - Noriday 350 microgram tablets (norethisterone, Pfizer, PL000571019). This page covers the progestogen-only pill as a class, and other products in the class differ and are not covered: other brands and other progestogens have their own SPC with their own strength, starting instructions and missed-pill rule, and the missed-pill window below must not be applied to them without checking that product's own SPC. No maximum dose applies beyond one pill per day. MISSED PILLS (Noriday SPC section 4.2): if a pill is missed within 3 hours of the correct dosage time, the missed pill should be taken as soon as possible, which ensures contraceptive protection is maintained. If a pill is taken 3 or more hours late, the woman should take the last missed pill as soon as possible and continue to take the rest of the pills in the normal manner, but an alternative method such as a condom is recommended for the next 7 days to provide continued contraceptive protection. CHANGING FROM ANOTHER ORAL CONTRACEPTIVE: the first pill is taken on the day immediately after finishing the previous pack. AFTER CHILDBIRTH: the first pill should be taken on the 21st day after childbirth, which protects immediately; if there is any delay, contraception may not be established until 7 days after the first pill and extra contraceptive methods are needed. AFTER A MISCARRIAGE OR ABORTION: the first pill can be taken on the next day, with immediate protection. VOMITING AND DIARRHOEA: gastrointestinal upset may interfere with absorption and reduce contraceptive efficacy; the woman should continue to take Noriday and also use another contraceptive method during the period of gastrointestinal upset and for the next 7 days. Indication (section 4.1): progestogen-only oral contraceptive, particularly useful for women for whom oestrogens may not be appropriate. The SPC gives no separate paediatric or adolescent posology. Each tablet contains 62.25 mg lactose (as monohydrate).

Dose adjustments

Renal

SPC section 4.2 gives no renal dose adjustment. Section 4.4: use in women with a history of migraine, epilepsy, or cardiac or renal dysfunction may result in exacerbation of these disorders because of fluid retention.

Hepatic

SPC section 4.3: contraindicated in acute or severe chronic liver diseases including past or present liver tumours and Dubin-Johnson or Rotor syndrome, in active liver disease, and with a history during pregnancy of idiopathic jaundice or severe pruritus. Section 4.4: take caution with a past history of liver disease; discontinue if jaundice occurs; a hepatic tumour should be considered in the differential diagnosis of upper abdominal pain, enlarged liver or signs of intra-abdominal haemorrhage.

Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via MHRA Products — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Known, suspected, or a past history of breast, genital or hormone dependent cancer (section 4.3)
  • Acute or severe chronic liver diseases including past or present liver tumours, Dubin-Johnson or Rotor syndrome; active liver disease (section 4.3)
  • History during pregnancy of idiopathic jaundice or severe pruritus (section 4.3)
  • Disorders of lipid metabolism (section 4.3)
  • Undiagnosed abnormal vaginal bleeding (section 4.3)
  • Known or suspected pregnancy (section 4.3)
  • Hypersensitivity to the active substance or to any of the excipients listed in section 6.1 (section 4.3)
  • Existing or history of thrombophlebitis, thromboembolic disorders, cerebral vascular disease, myocardial infarction, angina or coronary artery disease, in the absence of long-term epidemiological studies with progestogen-only oral contraceptives (section 4.3)

Side effects

  • Cycle irregularity during the first few months, spotting or breakthrough bleeding, amenorrhoea; if two consecutive periods are missed, pregnancy should be ruled out before continuing (section 4.8)
  • Breast discomfort, gastrointestinal symptoms, rash, headaches, migraine, depression, fatigue, nervousness, disturbance of appetite and changes in weight, libido changes (section 4.8)
  • Hepatic adenoma (in very rare cases; rupture may cause death through intra-abdominal haemorrhage) (sections 4.4, 4.8)
  • Hypertension, usually reversible on discontinuing treatment, in a small percentage of women taking oral contraceptives (section 4.8)
  • Thromboembolic and thrombotic disease, cardiovascular risk raised by smoking, hypercholesterolaemia, obesity, diabetes, history of pre-eclamptic toxaemia and increasing age (section 4.4)
  • A slightly increased relative risk of breast cancer diagnosis in current and recent users of oral contraceptives (section 4.4)
  • Progestogen-only oral contraceptives may offer less protection against ectopic pregnancy than against intrauterine pregnancy (section 4.4)
  • This side-effect list may be incomplete — check the full SPC.

Interactions

  • St John's wort (Hypericum perforatum) should not be taken concomitantly - possible loss of contraceptive effect (section 4.5)
  • Some drugs may modify the metabolism of Noriday and reduce effectiveness, including certain sedatives, antibiotics and antiepileptics; use an alternative method such as a condom while such agents are used (section 4.5)
  • Serum levels of prednisone, prednisolone, cloprednol and possibly other corticosteroids are considerably increased in those taking oral contraceptives, with increased therapeutic and toxic effects (section 4.5)

Monitoring

  • Assessment before starting and at regular intervals: personal and family medical history, blood pressure and, if judged appropriate, breast, abdominal and pelvic examination including cervical cytology (section 4.4)
  • Regular surveillance for the development of thromboembolism and cardiovascular risk factors; re-assess the risk/benefit ratio after age 35 (section 4.4)
  • Discontinue at least 4 weeks before elective surgery or prolonged immobilisation; it would be reasonable to resume 2 weeks after surgery provided the woman is ambulant (section 4.4)
  • Discontinue if there is loss of vision or ocular changes, onset or aggravation of migraine or new recurrent, persistent or severe headache, suspected thrombosis or infarction, a significant rise in blood pressure, or jaundice (section 4.4)
  • Caution with contact lenses, impaired carbohydrate tolerance, depression, gallstones, varicose veins, hypertension, asthma, or diseases prone to worsen in pregnancy (multiple sclerosis, porphyria, tetany, otosclerosis) (section 4.4)

Clinical monograph

How it works

It works mainly by thickening cervical mucus to impede sperm, with some formulations also inhibiting ovulation, and it thins the endometrium.

Prescribing in practice

  • Consistent daily timing is important; missed or late pills, and conditions causing vomiting or severe diarrhoea, can reduce contraceptive protection and may require additional precautions.
  • If pregnancy occurs on the progestogen-only pill, an ectopic pregnancy should be excluded as a cause of abdominal pain.
  • Irregular or unscheduled bleeding is a common reason for discontinuation but unexpected bleeding should still prompt consideration of other causes.

Monitoring

Monitoring is largely clinical, reviewing bleeding patterns, adherence, blood pressure and any new risk factors at follow-up.

Counselling the patient

  • Take the pill at around the same time each day for reliable protection.
  • Use additional contraception if a pill is missed or late, following the advice in the leaflet.
  • Irregular bleeding is common, especially early on, but seek review if it is troublesome or persistent.

Evidence & guidelines

The progestogen-only pill is a long-established contraceptive option covered by UK sexual and reproductive health guidance.

Reference: FSRH Progestogen-Only Pills Guideline 2022; UKMEC 2016; Confirm identity and dosing against the manufacturer SPC (eMC) and NICE. Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

Calculators
Pathways