norethisterone: prescribing and clinical use
Focused clinical detail for use alongside current product information, local policy and patient-specific assessment.
norethisterone: clinical details
Prescribing considerations
- Confirm the exact product because Utovlan and Primolut N have different licensed indications and contraindications.
- Exclude pregnancy and investigate unexplained genital bleeding before prescribing.
- Assess thrombotic and arterial risk, migraine features, liver disease, blood pressure, diabetes, mood history, planned surgery and immobilisation.
- Review prescribed, non-prescribed and herbal medicines for clinically relevant interactions.
- Consider lactose content in patients with relevant hereditary carbohydrate-intolerance disorders.
Contraindications and cautions
- Across the selected products: pregnancy, hypersensitivity, current or previous idiopathic venous thromboembolism, active or recent arterial thromboembolic disease, significant liver dysfunction and unexplained genital bleeding.
- Primolut N additionally lists lactation, high venous or arterial thrombotic risk, migraine with focal neurological symptoms, diabetes with vascular involvement, liver tumours, hormone-dependent malignancy and untreated endometrial hyperplasia.
- Utovlan additionally lists porphyria and specified histories of pregnancy-associated jaundice, severe pruritus or pemphigoid gestationis.
Monitoring
- Investigate persistent or recurrent heavy bleeding.
- Monitor clinically for thromboembolism, new migraine, visual disturbance, jaundice, significant blood-pressure rise, fluid retention and mood deterioration.
- Check carbohydrate metabolism before and during Primolut N treatment in patients with diabetes.
- Be aware that progestogens can affect hepatic, thyroid and coagulation laboratory results.
Clinical pharmacology
Norethisterone is an orally absorbed estrane progestogen with progesterone-like activity, ovulation suppression and direct endometrial effects. It has weak androgenic and oestrogenic properties and is partly converted to ethinylestradiol.
Formulation and product differences
- Both selected products are oral tablets containing lactose, but their tablet markings, manufacturers, pack presentations and storage particulars differ.
- Their licences and contraindications are not interchangeable: Utovlan includes disseminated breast carcinoma, whereas Primolut N contraindicates known, past or suspected hormone-dependent malignancy and has broader thrombotic contraindications.
norethisterone preparations and strengths
Tablet
Route: Oral
Strengths: 5 mg
norethisterone interactions
Check prescribed, over-the-counter and herbal products before treatment. Important interactions include:
Enzyme-inducing antiseizure medicines, including carbamazepine, phenytoin, primidone and barbiturates
They can increase norethisterone clearance, causing altered bleeding or reduced therapeutic effect.
Rifampicin or rifabutin
These enzyme inducers can lower norethisterone exposure and reduce its effect.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.