Bioidentical hormones are artificial hormones that are similar to the hormones produced by the human body. They are used as treatment for people whose own hormones are low or unbalanced. Some people benefit from bioidentical hormones, but there are risks to treatment.
Bioidentical hormones are processed hormones designed to mimic the hormones made by your body’s glands. Taking bioidentical hormones can help people who experience symptoms of low or unbalanced hormones. This is often the case for people experiencing symptoms of perimenopause or menopause.
Hormones are chemicals made by your endocrine glands. They are messengers that tell other parts of your body how and when to work. Hormones affect many systems and functions in your body. Even the slightest imbalance can cause symptoms that interfere with your day. Healthcare providers may recommend hormone replacement therapy as a treatment for these symptoms.
Bioidentical hormone therapy (BHRT) uses processed hormones that come from plants. Estrogen, progesterone and testosterone are the most commonly used bioidentical hormones.
Some prescription forms of bioidentical hormones are premade by drug companies. The U.S. Food and Drug Administration (FDA) has approved certain types of bioidentical hormones. Other forms of bioidentical hormones are custom-made by a pharmacist based on a healthcare provider's prescription. These are compounded (or mixed) bioidentical hormones.
The compounded forms have not been tested and approved by the FDA. Though it is often advertised that products that are made from plants are "natural" choices, they are altered in a lab so are no longer natural when done with processing.
Both the FDA-approved and compounded hormones come in various doses and forms (pills, creams, gels, sprays and vaginal inserts). Be sure to talk to your healthcare provider to find out which type of BHRT is right for you.
Compounded bioidentical hormones are advertised as being a safer, more effective, natural and individualized alternative to conventional hormone therapy. However, these claims remain unsupported. Also, the lack of FDA oversight for compounded hormones generates additional risks regarding the purity and safety of compounded bioidentical hormones. Although custom hormone combinations often include blends of the same ingredients found in FDA-approved bioidentical hormones, some include additional hormones. These additional hormones have not had adequate testing and are not included in any FDA-approved products.
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Using any type of hormone therapy is a decision made between you and your healthcare provider after carefully weighing the risks and benefits. Bioidentical hormones have been controversial, and many are not FDA-approved, but that doesn't mean your healthcare provider will rule them out as a treatment option.
If you've had or are at high risk for the following conditions, hormone therapy may not be safe:
The levels of certain hormones in your body go down with age. These hormones include estrogen, progesterone and testosterone. Some common effects of low hormones include:
Replacing these lost or low hormones is the goal of bioidentical hormone therapy or conventional hormone therapy. Once hormone levels are increased, most people see their symptoms improve. However, there is not much evidence to support that bioidentical hormones are equal to conventional hormone therapy. Your healthcare provider can discuss your options for hormone replacement with you based on your symptoms and health history.
One study suggests that approximately 1 to 2.5 million women in the U.S. over age 40 are using compounded bioidentical hormones.
Bioidentical hormones come in many forms. These include:
Your healthcare provider will decide which method is best for you. You may try more than one way before you find one that works well for you.
People on hormone treatment are watched very closely by their healthcare providers. The goal is to relieve symptoms with the lowest dose possible for the shortest amount of time. Depending on your healthcare provider, you might have routine blood, urine or saliva tests to check your hormone levels. Your healthcare provider may adjust your dose based on your changing hormone needs.
The FDA recommends against using hormone levels to guide the dosing of hormone therapy in women, as normal levels fluctuate day to day. In particular, salivary hormone levels are known to fluctuate and have not been shown to be related to menopausal symptoms.
The amount of time it takes for bioidentical hormones to work varies. Some people may feel mild relief within a few weeks. Most of the time, it takes about three months to feel the full effect of any type of hormone therapy.
It has been shown in research studies that there are risks to taking hormones. It can increase the risk of blood clots, stroke, and gallbladder disease. Your risk of heart disease and breast cancer may also increase if you are older or use hormonal therapy for an extended period. Many healthcare providers who use bioidentical hormones claim they are safer than traditional hormone therapy treatments. But there have been no large research studies of bioidentical hormones to show evidence of this.
The bioidentical hormones that are approved by the FDA have been tested for safety. They have passed the FDA's strict standards and are safe for people to use. Like all hormone treatments, there are risks involved. You should weigh the pros and cons of even the FDA-approved bioidentical hormones with your healthcare provider.
There are risks to taking compounded bioidentical hormones, but in some cases, they may be a better choice. Compounded bioidentical hormones are not FDA-approved. They are not tested for safety or effectiveness. Many major medical groups do not support using them because not enough is known about their safety and long-term side effects.
When the FDA approves a drug, the drug company must report any side effects they are told about. These side effects are included in the paperwork you get when you pick your medication up at the pharmacy. Pharmacies that compound hormones do not have to report drug side effects to the FDA or provide paperwork. This contributes to the myth that compounded hormones are safer when healthcare providers don't know all of the possible side effects of these hormones.
Side effects can occur, especially after the first dose. Your body is not used to the new level of hormones. Many side effects get better as the body adjusts to the new level of hormones. In some cases, the dose may need to be changed.
Some common side effects of bioidentical hormones include:
You may itch or get red around the area where you apply your hormones if you use a patch, cream or gel.
Yes, they work for some people. You will have different results depending on your symptoms and health history. Talk with your healthcare provider about bioidentical hormones and what form may work best for you. In some cases, your healthcare provider may recommend against using bioidentical hormones in favor of a more traditional hormone replacement therapy option.
Call your healthcare provider if you have any negative side effects after getting a dose of hormones. If you have a side effect that you cannot manage or does not go away in a short time, your hormone level might be too high. Talk to your healthcare provider before hormone treatment so you know what to expect.
Yes, weight gain is a side effect of bioidentical hormones.
A note from Cleveland Clinic
Bioidentical hormones are used to help people manage symptoms of menopause or other hormonal imbalances. The FDA does not approve some bioidentical hormones. All hormone replacement therapy comes with risks. Compounded bioidentical hormones may come with more risk because their effects are not well studied. Talk to your healthcare provider about the pros and cons of hormone replacement. Most importantly, know that you do not need to live with unpleasant symptoms of low hormones. Your provider can help safely manage your symptoms.
Last reviewed by a Cleveland Clinic medical professional on 04/15/2022.
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