Prometrium (Micronised Progesterone)
Understanding cyclical and continuous use of Prometrium in menopausal hormone therapy
What is Prometrium?
Prometrium is a natural micronised progesterone capsule — bioidentical to the progesterone your body makes. It is used alongside oestrogen therapy (such as Estrogel or Sandrena) to protect the uterine lining (endometrium) from over-stimulation by oestrogen.
Because it is bioidentical, Prometrium is generally well-tolerated and has a more favourable side-effect profile than older synthetic progestogens.
🌿 Who needs Prometrium?
Prometrium is prescribed for women who still have their uterus. It is typically not needed if you have had a hysterectomy. Your doctor will advise you based on your individual circumstances.
Two Ways to Take Prometrium
Your doctor will prescribe one of two regimens, depending on your stage of menopause and symptoms:
Cyclical Use
Take Prometrium for 12–14 days per month, on the days your doctor specifies. You do not take it every day. The exact days will be on your prescription.
Take Prometrium from Day _____ to Day _____ each month.
A withdrawal bleed (similar to a light period) usually occurs in the days after you stop Prometrium each month. This is normal and expected.
Continuous Use
Take Prometrium every day, without a break. This is more common after menopause is established.
Aim for period-free (amenorrhoeic) therapy. Spotting may occur in the first few months.
How to Take Prometrium
Swallow the capsules whole — do not chew, crush, or open them. Take the number of capsules prescribed by your doctor.
Take at bedtime with a full glass of water — Prometrium can cause drowsiness, which is actually a benefit for sleep quality.
Do not take with food unless your doctor specifically advises it (food can alter absorption).
If you forget a dose, take it as soon as you remember that evening. If it is already the next day, skip the missed dose.
Always follow the specific number of capsules and regimen printed on your prescription label.
💤 Sleep benefit
Many women find that Prometrium improves sleep quality. The mild sedating effect is a natural property of progesterone — taking it at bedtime makes this work in your favour.
What to Expect – Withdrawal Bleeds
If you are on cyclical use, a withdrawal bleed (light, period-like bleed) usually occurs in the days after you stop Prometrium each month. This is normal and expected.
⚠️ When to contact your doctor
Bleeding that is heavy or painful
Bleeding occurring more than 6 months into continuous therapy
Any unexpected or unusual bleeding pattern
Reference Graphic
Prometrium dosing calendars — see panel 3 of the Arami Hormone Therapy Guide
Not sure which Prometrium regimen is right for you?
Book a consultation with our team to review your hormone therapy and get personalised advice.
Medical Disclaimer
This information is general in nature and does not replace professional medical advice. Always follow the specific instructions provided by your doctor or pharmacist, and refer to the Consumer Medicines Information (CMI) leaflet supplied with your medication. If you experience unexpected side effects or have concerns about your treatment, contact your healthcare provider promptly.