Caverject vs Prometrium: side-by-side comparison
Caverject (Erectile Dysfunction (ED)) 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 | Caverject | Prometrium |
|---|---|---|
| Active ingredient | Alprostadil | Progesterone |
| Manufacturer | Pfizer | Catalent / Virtus |
| Class | Erectile Dysfunction (ED) | Hormones and Birth Control |
| Strengths | 10mcg, 20mcg, 40mcg | 100mg, 200mg |
| Forms | injection | capsule |
What's the same
Caverject 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
Caverject belongs to Erectile Dysfunction (ED) 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
Caverject: Alprostadil binds prostaglandin E receptors on smooth muscle of the corpus cavernosum, triggering cAMP-mediated relaxation of cavernosal smooth muscle independent of the nitric oxide pathway used by PDE5 inhibitors. Prometrium: Progesterone in Prometrium binds to progesterone receptors and modulates gene expression in reproductive and other tissues.
When Caverject is preferred
Caverject is approved for erectile dysfunction of vasculogenic, neurogenic, psychogenic or mixed aetiology in adult men.
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 Caverject or Prometrium better? ▾
Caverject 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 Caverject to Prometrium? ▾
Switching between Caverject 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 Caverject 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 Caverject comparisons
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.