Is Prometrium The Same Thing As Progesterone?

In our latest question and answer, our pharmacist discusses whether or not Prometrium is the same thing as progesterone.


Hi, my question is the following: Are Prometrium and progesterone the same medication? Thank you in advance.

Asked by Beth On May 09, 2023

Answered by
Medical Content Reviewed By HelloPharmacist Staff

Published May 10, 2023
Last updated Jul 18, 2024

Key points

  • Prometrium is a brand-name product that contains micronized progesterone.
  • Prometrium is, therefore, the 'same' as progesterone. It is formulated as 'micronized progesterone' to improve absorption and overall effectiveness.


Yes, Prometrium and progesterone are the same in the sense that Prometrium is a brand-name product that contains micronized progesterone. Prometrium's micronized progesterone is structurally the same as the progesterone produced by the human ovary, meaning that it is 'bioidentical'. It is not synthetic.

As mentioned, Prometrium is a brand name, and it is available generically as 'progesterone'. Both the brand Prometrium and generic progesterone are available in 100mg and 200mg capsules.

The 'micronized' part of 'micronized progesterone' is simply referring to how the drug is formulated. 

Progesterone is micronized to increase its absorption and effectiveness in the body. When progesterone is micronized, it is broken down into smaller particles, which allows it to be better absorbed by the body when taken orally. This can increase the hormone's effectiveness and reduce the amount needed for treatment.

Other Forms Of Progesterone

Since you're asking about progesterone, I think it's worth pointing out that there are other drugs on the market that are classified as 'progestins'. A 'progestin' is a synthetic compound that is chemically similar to the naturally occurring hormone progesterone. Progestins are designed to have similar effects as progesterone in the body.

However, progestins may have additional effects and can be modified to have different properties, such as a longer half-life or greater potency.

The most commonly used 'progestin' is medroxyprogesterone. Technically, it is not progesterone but has progesterone-like effects.

This answer isn't intended to get into all the differences between progesterone and medroxyprogesterone, but I will say that progesterone is a natural hormone that is the same as the progesterone produced in a woman's ovaries. It is often preferred over the synthetic progestin, medroxyprogesterone, because it has fewer side effects.

For example, medroxyprogesterone has been linked to increased risks of heart disease and breast cancer. Micronized progesterone, on the other hand, does not seem to have these risks but there is still somewhat limited information available on the safety of these hormones overall.

Final Words

I hope this answer helped! Reach back out anytime.


  • Menopausal hormone replacement therapy with continuous daily oral micronized estradiol and progesterone, PubMed
  • Prometrium Prescribing Information, AccessFDA

About the Pharmacist

Dr. Brian Staiger, PharmD

Dr. Brian has been practicing pharmacy for over 13 years and has wide-ranging experiences in many different areas of the profession. From retail, clinical, program development, and administrative responsibilities, he's your knowledgeable and go-to source for all your pharmacy and medication-related questions! Dr. Brian Staiger also has herbalist training and educational certificates in the field of medical ethnobotany. Feel free to send him an email at [email protected]! You can also connect with Dr. Brian Staiger on LinkedIn.

Recent Questions