Aygestin vs Prometrium: side-by-side comparison
Aygestin (Women's Sexual Health) and Prometrium (Hormones and Birth Control) belong to different therapeutic classes and are rarely interchangeable. This page compares the medications' purposes, mechanisms and the situations where each is used.
| Property | Aygestin | Prometrium |
|---|---|---|
| Active ingredient | Norethindrone | Progesterone |
| Manufacturer | Various generics | Catalent / Virtus |
| Class | Women's Sexual Health | Hormones and Birth Control |
| Strengths | 5mg | 100mg, 200mg |
| Forms | tablet | capsule |
What's the same
Aygestin and Prometrium are used in very different patients, and the points in common are limited. The main shared element is that both meet regulatory standards for efficacy and safety and benefit from pharmacist oversight.
Key differences
Aygestin belongs to Women's Sexual Health while Prometrium belongs to Hormones and Birth Control. Indications, mechanisms and target populations differ. The comparison is most useful when a clinician has mentioned both medications and the patient wants to understand where each fits.
Mechanism and action
Aygestin: Norethindrone binds to progesterone receptors and exerts progestational effects: thickening cervical mucus, suppressing the LH surge, thinning the endometrium and reducing endometrial implant activity in endometriosis. Prometrium: Progesterone in Prometrium binds to progesterone receptors and modulates gene expression in reproductive and other tissues.
When Aygestin is preferred
Aygestin is approved for endometriosis-associated pain, abnormal uterine bleeding due to hormonal imbalance, and secondary amenorrhoea.
When Prometrium is preferred
Prometrium is approved for endometrial protection in postmenopausal women receiving estrogen, secondary amenorrhoea and selected ART indications.
Frequently asked questions
Is Aygestin or Prometrium better? ▾
Aygestin and Prometrium are not interchangeable — they treat different conditions. Asking which is "better" is meaningful only when a clinician has weighed both for the same specific clinical scenario.
Can I switch from Aygestin to Prometrium? ▾
Switching between Aygestin and Prometrium is rarely an appropriate decision since they belong to different classes and treat different conditions. The real question is usually whether the diagnosis calls for one medication or the other — which the prescriber resolves.
Do Aygestin and Prometrium have the same side effects? ▾
No — they belong to different classes and have distinct side-effect profiles. Each medication has its own prescribing information.
More Aygestin comparisons
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.