What is Progesterone USP?

Progesterone USP is prescribed by physicians to supplement a woman's natural production of the hormone. USP stands for United States Pharmacopoeia, which is the national standard of purity for substances used in the manufacture of drugs and cosmetics. Natural progesterone USP simply confirms that the progesterone is molecularly identical to the progesterone produced by the human body, not the synthetic version generally referred to as progestin.

First isolated in 1934, progesterone USP is a white or creamy white crystalline powder, is odorless, stable in the air, and is nearly insoluble in water. These natural hormones, derived from wild yam or soy, are natural to what your body produces so they act in the same way.

''Micronized'' progesterone is progesterone USP, the natural form of progesterone, broken down into very tiny particles. The process of micronization allows for steady, even absorption of the medication. In this country, micronized progesterone is available as a bulk powder to pharmacies that specially prepare, or ''compound,'' the powder into capsules or slow-release tablets in different doses as prescribed by physicians.

Progesterone vs. Progestin

Natural or natural progesterone USP should not be confused with synthetic progestin. Progestins are derivatives of progesterone used in medications like oral contraceptives or drugs like Provera. While progestin's chemical structure is only slightly different, its effects in the body can be very different from natural progesterone. For example, synthetic progestins can inhibit ovulation, thus oppressing the body's output of its own natural progesterone. Synthetic progestin often intensifies rather than relieves PMS symptoms.

Forms of Administration

Natural progesterone USP is commonly prescribed for women experiencing symptoms of PMS, perimenopause, menopause, postpartum depression, and for pregnancy maintenance. Physicians prescribing natural progesterone have several dosage forms to choose between. Important considerations for physicians when choosing the appropriate dosage include:

• Absorption characteristics - how much of the medication is absorbed, how fast, and how long it lasts
• Symptom control and side effects
• Ease of administration
• Expense

Dosing Points to Remember

Patients and physicians should keep in mind that progesterone replacement therapy must be individualized for each patient. Saliva hormone testing can take the guesswork out of dosing and help find the lowest effective dose for each, individual woman.

• For cycling women, typical recommended dosing is Progesterone 300 mg Even Release Tablet two times per day, days 14-28, based on a 28-day cycle.
• For women no longer cycling or post-hysterectomy, dosing is daily.