Citrus X aurantium

Bitter Orange

Citrus X aurantium

Bitter Orange

Citrus X aurantium, commonly called bitter orange, Seville orange, or sour orange, is a distinct species from the commonly consumed sweet orange, Citrus X sinensis. The ‘X’ present in the Latin binomials for both orange species represent hybridization, and is included in the Latin names for all popular citrus fruit (C. X limon = lemon, C. X paradisi = grapefruit, and C. X aurantiifolia = key lime). Bitter orange belongs to the Rutaceae family along with all other citrus fruits, and the medicinal plants of Buchu, Prickly Ash, and Rue. Bitter orange is thought to be native to the tropical and semi-tropical regions of India & China. The use of bitter orange migrated to the middle east and beyond, earning a place in the European materia medica. Bitter orange was introduced to the Americas during 16th century expeditions and is now both naturalized and cultivated in tropical regions worldwide.

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Traditional Health Benefits of Bitter Orange

Respiratory Support, Digestive Support

What is Bitter Orange Used for?

The use of bitter orange originally descends from traditional Chinese medicine, though the use of bitter orange has been adopted into the European practice of herbal medicine as well. Both modalities utilize extracts and preparations of fruit rind. As a bitter herb, bitter orange stimulates the release of bile from the gallbladder, which in turn supports healthy digestion of foods (especially dietary fats), and regular bowel movements. The volatile oils of bitter orange are thought to be relaxing to the smooth muscle of the GI tract, and orange marmalade (traditionally made with bitter and not sweet orange) can make a good breakfast for those with stagnant digestion. Bitter orange is not typically eaten raw. It is usually cooked or processed and used for its flavor and aroma in medicine, cooking, and aromatherapy. The rind can be cooked, extracted, or expressed, the latter resulting in an essential oil. Energetically, bitter orange is considered cooling. The volatile oils, which can have a calming effect on muscular contraction, have a calming effect on the nervous system as well. Bitter orange essential oil is considered relaxing and is used in aromatherapy to uplift and calm the nervous system. Internally, the essential oil and the specific monoterpene limonene was found to support gastric mucus production, which helps to maintain the health of the GI tract tissues. Another monoterpene from bitter orange, β-myrcene, has also been highlighted as supporting the integrity of the gastric mucosa, and supporting cellular glutathione levels. Bitter orange became the subject of controversy due to concentrated extracts containing especially high amounts of synephrine (~6%) that became associated with safety concerns. Fresh bitter orange fruit contains approximately 0.02% p-synephrine. Bitter orange is typically used in small, synergistic amounts in herbal formulas, and synephrine is even produced in the body in small amounts by conversation from tyramine. It is important to note that a single compound from a plant is not representative of the chemical complexity or actions of the whole plant. Therefore, a single compound’s effects (i.e. synephrine) are not equivalent to the effects and chemical complexity of a full spectrum extract (i.e. bitter orange).

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Active Constituents of Bitter Orange

Flavonoids (hesperidin, neohesperidin, and naringin), polymethoxyflavones (nobiletin, and tangeretin), terpenes (limonene, linalool, and myrcene), alkaloids (p-synephrine), furanocoumarins (bergapten and oxypeucedanin)

Parts Used

Essential oil of the fruit rind

Additional Resources

1. 2. Fugh-Berman, A., & Myers, A. (2004). Citrus aurantium, an Ingredient of Dietary Supplements Marketed for Weight Loss: Current Status of Clinical and Basic Research. Experimental Biology and Medicine, 229(8), 698 704. doi:10.1177/153537020422900802 3. Moslemi, F., Alijaniha, F., Naseri, M., Kazemnejad, A., Charkhkar, M., & Heidari, M. R. (2019). The Journal of Alternative and Complementary Medicine. doi:10.1089/acm.2019.0061 4. Shara, M., Stohs, S. J., & Smadi, M. M. (2017). Safety evaluation of p-synephrine following 15 days of oral administration to healthy subjects: A clinical study. Phytotherapy Research, 32(1), 125–131. doi:10.1002/ptr.5956 5. Heydari, N., Abootalebi, M., Jamalimoghadam, N., Kasraeian, M., Emamghoreishi, M., & Akbarzadeh, M. (2018). Complementary Therapies in Clinical Practice, 32, 1–5. doi:10.1016/j.ctcp.2018.04.006 6. Shara, M., Stohs, S. J., & Mukattash, T. L. (2016). Cardiovascular Safety of Oral p-Synephrine (Bitter Orange) in Healthy Subjects: A Randomized Placebo-Controlled Cross-over Clinical Trial. Phytotherapy Research, 30(5), 842–847. doi:10.1002/ptr.5590 7. Kaats, G. R., Miller, H., Preuss, H. G., & Stohs, S. J. (2013). A 60day double-blind, placebo-controlled safety study involving Citrus aurantium (bitter orange) extract. Food and Chemical Toxicology, 55, 358–362. doi:10.1016/j.fct.2013.01.013 8. Penzak, S. R., Jann, M. W., Cold, J. A., Hon, Y. Y., Desai, H. D., & Gurley, B. J. (2001). Seville (sour) Orange Juice: Synephrine Content and Cardiovascular Effects in Normotensive Adults. The Journal of Clinical Pharmacology, 41(10), 1059–1063. doi:10.1177/00912700122012652 9. Nadkarni, K.M. Dr. K.M. Nadkarni’s Indian Materia Medica. Vol. 1. 3rd Edition. Bombay Popular Prakashan. 1976. 10. Wood, Matthew. The Earthwise Herbal: The Complete Guide to Old World Medicinal Plants. North Atlantic Books: Berkeley, CA. 2008. 11. Suntar, I., Khan, H., Patel, S., Celano, R., & Rastrelli, L. (2018). An Overview on Citrus aurantium L.: Its Functions as Food Ingredient and Therapeutic Agent. Oxidative Medicine and Cellular Longevity, 2018, 1-12. doi:10.1155/2018/7864269

Important Precautions

Essential oils are not for internal use in pregnancy or lactation. If you have a medical condition or take medications please consult with your doctor prior to use


This information in our Herbal Reference Guide is intended only as a general reference for further exploration, and is not a replacement for professional health advice. This content does not provide dosage information, format recommendations, toxicity levels, or possible interactions with prescription drugs. Accordingly, this information should be used only under the direct supervision of a qualified health practitioner such as a naturopathic physician.

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