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Traditional Chinese Medicine


Denise Millstine

, MD, Mayo Clinic

Reviewed/Revised Dec 2023

Originating > 2000 years ago, traditional Chinese medicine (TCM) is a medical system based on the philosophy that illness results from improper flow of the life force (qi). The movement of qi is restored by balancing the opposing forces of yin and yang, which manifest in the body as cold and heat, internal and external, and deficiency and excess.

Various practices are used to preserve and restore qi and thus health. Most commonly used are

Other practices include diet, massage, and meditative exercise called qi gong.

TCM often uses diagnostic categories that do not correspond to current scientific understanding of biology and illness (eg, general deficiency, excess of yin or yang).

Evidence for Traditional Chinese Medicine

Obtaining high-quality evidence is difficult, mainly because the active ingredients in TCM herbs are not purified, are often unidentified, and may be numerous. Thus, determining the dose is difficult or impossible, and the dose may vary from one source of herbs to another. Information about bioavailability, pharmacokinetics, and pharmacodynamics is usually unavailable. Also, active ingredients may interact with each other in complex and variable ways.

Chinese herbal medicine traditionally uses formulas containing mixtures of herbs to treat various disorders. Traditional formulas can be studied as a whole, or each herb in the formula can be studied separately. One herb, used by itself, may not be as effective and may have adverse effects. Nevertheless, current conventional research favors study of single herbs to better control for variables. Another problem is the large number of herbal mixtures that could be studied.

Systematic reviews and meta-analyses of studies (most done in China) have shown evidence for efficacy of TCM for the following:

Many of these reviews had significant limitations, suggesting the need for confirmation with further prospective studies.

Studies of TCM herbs and herbal mixtures for irritable bowel syndrome have had mixed results, and reviews of these studies conclude that more rigorous studies are required.

Possible Adverse Effects

One problem with TCM is the standardization and quality control of Chinese herbs. Many are unregulated in Asia; they may be contaminated with heavy metals from polluted ground water or may be adulterated with drugs such as antibiotics or corticosteroids. Ingredients are often substituted, partly because the names of the herbs are translated incorrectly.

In herbal mixtures, adverse effects may also result from interactions between active ingredients. Interactions can also occur between TCM herbs and medications.


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  • 2. Wang YT, Zhang RQ, Wang SF, et al: A systematic review and meta-analysis of integrated traditional Chinese medicine and Western medicine in treating glomerulosclerosis. Medicine (Baltimore) 100(7):e24799, 2021. doi: 10.1097/MD.0000000000024799

  • 3. Zhang H, Li M, Xu T: Therapeutic effect of Chinese herbal medicines for post-stroke depression: A meta-analysis of randomized controlled trials. Medicine (Baltimore) 100(1):e24173, 2021. doi: 10.1097/MD.0000000000024173

  • 4. Di YM, Yang L, Shergis JL, et al: Clinical evidence of Chinese medicine therapies for depression in women during perimenopause and menopause. Complement Ther Med 47:102071, 2019. doi: 10.1016/j.ctim.2019.03.019

  • 5. Zhou LP, Wang J, Xie RH, et al: The effects of Traditional Chinese Medicine as an auxiliary treatment for COVID-19: A systematic review and meta-analysis. J Altern Complement Med 27(3):225-237, 2021. doi: 10.1089/acm.2020.0310

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