Progesterone is not the same for every woman
On progesteronetherapy.com I read about withdrawal symptoms of progesterone.
I have a rare condition, that isn't actually so rare. Just unnoticed. Progesterone is metabolized, that means broken down by an enzyme. The enzyme Cytochrome P450 3A4 is not active in the same way in every person.
The enzyme that metabolizes progesterone is produced in the liver, and the digestive tract. The enzyme activity is genetically determined and also influenced by food.
The genetic testing can predict whether the enzyme activity is normal, decrease, or increased.
Depending on what kind of metabolizer you are (normal, poor, intermediate or rapid) you will react to progesterone. This is the reason why not every woman needs the same dose of progesterone. And some woman are sensitive to artificial progesterone.
I am a rare one. I am a rapid metabolizer, and I get allergic reactions to progesterone cream, even bioidentical ones. I also get horrible withdrawal symptoms (headache, weepiness, itchiness).
To manage menopause symptoms I take Cytochrome P450 3A4 inhibitors (like licorice, and astragalus). There are also inducers, that can boost the enzyme activity.