Consumers and some healthcare providers may think that the term bioidentical hormones refers to custom mixes (custom compounded) of one or more hormones in differing amounts, depending on an individual prescriber’s order. Consumers may also assume that custom-compounded hormone formulations contain FDA-tested and approved drugs and are therefore safe.
But neither of these is true. Many well-tested, FDA-approved hormone therapy products available at retail pharmacies meet the definition of bioidentical, that is, with the same chemical and molecular structure as hormones that are produced in the body. And although compounded formulations may contain the active ingredients in FDA-approved products, the formulations themselves have not been tested for quality, safety, and effectiveness. Some have been found to contain too much or too little of one or more hormones to be effective and safe, and they may not actually contain the prescribed amounts.
What’s more, a custom-compounded formulation will also contain other ingredients that either hold everything together (in the case of a rectal suppository, an under-the-tongue tablet, or an under-the-skin pellet) or provide a vehicle for applying the product onto the skin (such as a cream or gel) or into the body (such as a liquid for a nasal spray) that affect how the hormones are absorbed.
A few consumers may need custom-compounded products to avoid allergies to certain ingredients or to provide dosages or mixtures that are not available commercially. However, custom-compounded hormones can pose risks. They do not have government approval because individually mixed preparations have not been tested to prove that they are absorbed appropriately or provide predictable levels in blood and tissue. And there is no scientific evidence of the effects these combinations of hormones have on the body, either good or bad. Preparation methods vary from one pharmacist to another and from one pharmacy to another, which means that consumers may not receive consistent amounts of medication. In addition, inactive ingredients may vary, and there can be batch-to-batch differences. Reliable sterility and freedom from undesired contaminants are also concerns. What’s more, these preparations can be expensive because they are often not covered by insurance plans.