- What other names is Bitter Orange known by?
- What is Bitter Orange?
- How does Bitter Orange work?
- Are there safety concerns?
- Are there any interactions with medications?
- Dosing considerations for Bitter Orange.
Aurantii Fructus, Aurantii fructus immaturus, Aurantii pericarpium, Aurantium, Bigarade, Bigarade Orange, Bitter Orange Flower, Bitter Orange Peel, Chao Zhi Ke, Chisil, Citrus amara, Citrus aurantium, Citrus Aurantium Fruit, Citrus bigarradia, Citrus vulgaris, Extrait de Zeste d'Orange, Fleur d'Orange Amère, Flos Citri Auranti, Fructus Aurantii, Fructus Aurantii Immaturus, Green Orange, Kijitsu, Marmalade Orange, Methyl-Synephrine, Methyl-Synephrine HCl, Méthyl-Synéphrine HCl, Methyl Synephrine, N-Methyltyramine, Naranja Amarga, Neroli Oil, Norsynephrine, Octopamine, Octopamine HCl, Orange Amère, Orange de Séville, Orange Peel Extract, Orange Verte, Seville Orange, Shangzhou Zhiqiao, Sour Orange, Synephrine, Synéphrine, Synephrine HCl, Synéphrine HCl, Synephrine Hydrochloride, Zeste d'Orange Amère, Zhi Ke, Zhi Qiao, Zhi Shi.
Bitter orange is a plant. The peel, flower, leaf, fruit, and fruit juice are used to make medicine. Bitter orange oil is made from the peel.
Bitter orange, both taken by mouth and applied to the skin, has many uses. But so far, science has shown only that the oil, when applied to the skin, might be effective for treatment of fungal skin infections (ringworm, jock itch, and athlete's foot).
Bitter orange peel is also used to improve appetite, and, in surprising contrast, it is also used for weight loss. Other uses for the fruit and peel are upset stomach, nasal congestion, and chronic fatigue syndrome (CFS).
The bitter orange flower and bitter orange oil are used for gastrointestinal (GI) disorders including ulcers in the intestine, constipation, diarrhea, blood in feces, drooping (prolapsed) anus or rectum, and intestinal gas. These parts of the bitter orange plant are also used for regulating fat levels in the blood, lowering blood sugar in people with diabetes, stimulating the heart and circulation, "blood purification," disorders of liver and gallbladder, kidney and bladder diseases, and as a sedative for sleep disorders.
Bitter orange peel is applied to the skin for swelling (inflammation) of the eyelid and its lining, as well as the retina in the eye. It is also used for bleeding from the retina, exhaustion accompanying colds, headaches, nerve pain, muscular pain, joint pain, bruises, swelling of the veins (phlebitis), and bed sores.
In aromatherapy, the essential oil of bitter orange is applied to the skin and also inhaled as a painkiller.
In foods, bitter orange oil is used as a flavoring agent. The fruit is used for making marmalades and liqueurs such as Triple Sec, Grand Marnier, Cointreau, and Curacao. Because the fruit is so sour and bitter, it is rarely eaten, except in Iran and Mexico. The dried peel of the fruit is also used as a seasoning.
In manufacturing, bitter orange oil is used in pharmaceuticals, cosmetics, and soaps.
In Asian medicine, the entire dried unripe fruit is used primarily for digestive disorders.
Bitter orange is frequently used in "ephedra-free" products since the FDA banned ephedra in 2004 for serious side effects on the heart. Bitter orange and caffeine, a frequent combination in weight loss and bodybuilding products, can cause high blood pressure and increased heart rate in healthy adults with otherwise normal blood pressure. There is no evidence to suggest that bitter orange is any safer than ephedra.
Bitter orange (synephrine) is considered a banned substance by the National Collegiate Athletic Association (NCAA).
Before taking bitter orange, talk with your healthcare professional if you take any medications. It can interact with many drugs.
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Possibly Effective for...
- Treating fungal skin infections such as ringworm, athlete's foot, and jock itch. Applying bitter orange oil seems to help treat fungal skin infections.
Insufficient Evidence to Rate Effectiveness for...
- Diabetes. Early research suggests that drinking tea made from the leaves of Indian snakeroot and the fruit of bitter orange for 4 months appears to decrease blood sugar levels in people with diabetes.
- Indigestion. Early research suggests that taking a specific product containing bitter orange along with other ingredients (Zhizhu) three times daily for 4 weeks reduces indigestion.
- Weight loss. Research on the effects of bitter orange on weight are conflicting. Some research suggests that a combination of bitter orange, caffeine, and St. John's wort might help for weight reduction when used with a low calorie diet and exercise. Taking a specific combination product (Prograde Metabolism, Prograde Nutrition, Lutz, FL) containing bitter orange, raspberry ketone, caffeine, capsaicin, garlic, ginger, black pepper, cayenne pepper, and chromium along with diet and exercise for 8 weeks also seems to improve weight and energy. However, another study found that a combination of bitter orange, caffeine, and several other ingredients did not help people lose weight.
- Anxiety before surgery. Research suggests that taking bitter orange two hours before surgery reduces anxiety.
- Nasal congestion.
- Intestinal gas.
- Stomach and intestinal upset.
- Intestinal ulcers.
- Regulating cholesterol.
- Chronic fatigue syndrome (CFS).
- Liver and gallbladder problems.
- Stimulating the heart and circulation.
- Eye swelling.
- Nerve and muscle pain.
- Stimulating appetite.
- Mild sleep problems (insomnia).
- Other conditions.
Bitter orange has many chemicals that affect the nervous system. The concentration and effect of these chemicals can change depending on the part of the plant and the method used for preparation. These chemicals can squeeze blood vessels, increase blood pressure, and cause the heart to beat faster.
Bitter orange is LIKELY SAFE for children and adults when taken in the amounts found in food. Bitter orange essential oil is POSSIBLY SAFE when applied to the skin or inhaled as aromatherapy.
But bitter orange is POSSIBLY UNSAFE when taken as a supplement for a medical purpose such as weight loss. Bitter orange, particularly when taken with stimulants such as caffeine or caffeine-containing herbs, increases the risk for high blood pressure, fainting, heart attack, stroke, and other severe side effects.
Bitter orange can cause sensitivity to the sun. Wear sunblock outside, especially if you are light-skinned.
Special Precautions & Warnings:Pregnancy and breast-feeding: Bitter orange is LIKELY SAFE during pregnancy when used in the amounts found in food. However, it is POSSIBLY UNSAFE when used in medicinal amounts. The effects of bitter orange on breast-feeding infants aren't known. Stay on the safe side and avoid using bitter orange during pregnancy or breast-feeding.
Diabetes: Some evidence suggests that bitter orange may interfere with blood sugar control in patients with type 2 diabetes. Use with caution and monitor blood sugar levels closely.
High blood pressure: Some studies suggest that bitter orange, especially in combination with caffeine, can increase blood pressure in healthy people. Other studies have found no such blood pressure elevation. To date, there haven't been any studies looking at the effect of bitter orange on blood pressure in people who already have high blood pressure. Don't take a chance. Avoid using bitter orange, especially in combination with stimulants such as caffeine, if you have high blood pressure.
Heart disease: Using bitter orange, especially in combination with caffeine or other stimulants, might increase the risk of serious side effects in people with a particular heart problem called "long QT interval syndrome" (named after the wave pattern made by a electrocardiogram).
Irregular heartbeat (heart arrhythmia): Some studies suggest that bitter orange, especially in combination with caffeine, can increase heart rate in healthy people. Other studies have found no such effect on heart rate. So far, there have been no studies of the effect of bitter orange on people who have an irregular heartbeat. Avoid using bitter orange, especially in combination with stimulants such as caffeine, if you have an irregular heartbeat.
Surgery: Bitter orange acts like a stimulant, so it might interfere with surgery by increasing heart rate and blood pressure. Stop taking bitter orange at least 2 weeks before a scheduled surgery.
Medications for depression (MAOIs)Interaction Rating: Major Do not take this combination.
Bitter orange contains chemicals that stimulate the body. Some medications used for depression can increase these chemicals. Taking bitter orange with these medications used for depression might cause serious side effects including fast heartbeat, high blood pressure, seizures, nervousness, and others.
Some of these medications used for depression include phenelzine (Nardil), tranylcypromine (Parnate), and others.
Midazolam (Versed)Interaction Rating: Major Do not take this combination.
The body breaks down midazolam (Versed) to get rid of it. Bitter orange can decrease how quickly the body breaks down midazolam (Versed). Taking bitter orange along with midazolam (Versed) might increase the effects and side effects of midazolam (Versed).
Caffeine (Excedrin, Anacin, Vivarin, and others)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Bitter orange is a stimulant. Caffeine is also a stimulant. In combination, they can increase blood pressure and cause the heart to beat rapidly. This can cause serious adverse effects such as heat attack and stroke.
Dextromethorphan (Robitussin DM, and others)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
The body breaks down dextromethorphan (Robitussin DM, others) to get rid of it. Bitter orange might decrease how quickly the body breaks down dextromethorphan (Robitussin DM, others). Taking bitter orange along with dextromethorphan (Robitussin DM, others) might increase the effects and side effects of dextromethorphan (Robitussin DM, others).
Felodipine (Plendil)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Felodipine (Plendil) is used to lower blood pressure. The body breaks down felodipine (Plendil) to get rid of it. Bitter orange might decrease how quickly the body gets rid of felodipine (Plendil). Taking bitter orange along with felodipine (Plendil) might increase the effects and side effects of felodipine (Plendil).
Indinavir (Crixivan)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Indinavir (Crixivan) is used to treat HIV/AIDS. The body breaks down indinavir (Crixivan) to get rid of it. Bitter orange might decrease how quickly the body breaks down indinavir (Crixivan). Taking bitter orange along with indinavir (Crixivan) might increase the effects and side effects of indinavir (Crixivan).
Medications changed by the liver (Cytochrome P450 3A4 (CYP3A4) substrates)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Some medications are changed and broken down by the liver. Bitter orange might decrease how quickly the liver breaks down some of these medications. Taking bitter orange along with some medications that are broken down by the liver can increase the effects and side effects of some medications. Before taking bitter orange, talk to your healthcare provider if you are taking any medications that are changed by the liver.
Medications for diabetes (Antidiabetes drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Bitter orange might decrease blood sugar. Diabetes medications are also used to lower blood sugar. Taking bitter orange along with diabetes medications might cause your blood sugar to become too low. Monitor your blood sugar closely. The dose of your diabetes medication might need to be changed.
Some medications used for diabetes include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, metformin (Glucophage), pioglitazone (Actos), rosiglitazone (Avandia), and others.
Medications that can cause an irregular heartbeat (QT interval-prolonging drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Bitter orange might increase your heart rate. Taking bitter orange along with medications that can cause an irregular heartbeat might cause serious side effects including irregular heartbeat.
Some medications that can cause an irregular heartbeat include amiodarone (Cordarone), disopyramide (Norpace), dofetilide (Tikosyn), ibutilide (Corvert), procainamide (Pronestyl), quinidine, sotalol (Betapace), thioridazine (Mellaril), and many others.
Stimulant drugsInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Stimulant drugs speed up the nervous system. By speeding up the nervous system, stimulant medications can make you feel jittery and speed up your heartbeat. Bitter orange might also speed up the nervous system. Taking bitter orange along with stimulant drugs might cause serious problems including increased heart rate and high blood pressure. Avoid taking stimulant drugs along with bitter orange.
The following dose has been studied in scientific research:
APPLIED TO THE SKIN:
- For treatment of fungal skin infections: Pure oil of bitter orange has been applied once daily for 1-3 weeks.
Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).
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Akhlaghi, M., Shabanian, G., Rafieian-Kopaei, M., Parvin, N., Saadat, M., and Akhlaghi, M. Citrus aurantium blossom and preoperative anxiety. Rev Bras.Anestesiol. 2011;61(6):702-712. View abstract.
Arbo, M. D., Schmitt, G. C., Limberger, M. F., Charao, M. F., Moro, A. M., Ribeiro, G. L., Dallegrave, E., Garcia, S. C., Leal, M. B., and Limberger, R. P. Subchronic toxicity of Citrus aurantium L. (Rutaceae) extract and p-synephrine in mice. Regul.Toxicol.Pharmacol 2009;54(2):114-117. View abstract.
Bent, S., Padula, A., and Neuhaus, J. Safety and efficacy of citrus aurantium for weight loss. Am.J.Cardiol. 11-15-2004;94(10):1359-1361. View abstract.
Blumenthal, M., Goldberg, A., and Brinckmann, J. Herbal Medicine Expanded Commission E Monographs. 2000;
Calapai, G., Firenzuoli, F., Saitta, A., Squadrito, F. R., Arlotta, M., Costantino, G., and Inferrera, G. Antiobesity and cardiovascular toxic effects of Citrus aurantium extracts in the rat: a preliminary report. Fitoterapia 12-1-1999;70(6):586-592.
Campbell-Tofte, J. I., Molgaard, P., Josefsen, K., Abdallah, Z., Hansen, S. H., Cornett, C., Mu, H., Richter, E. A., Petersen, H. W., Norregaard, J. C., and Winther, K. Randomized and double-blinded pilot clinical study of the safety and anti-diabetic efficacy of the Rauvolfia-Citrus tea, as used in Nigerian traditional medicine. J Ethnopharmacol. 1-27-2011;133(2):402-411. View abstract.
Cherniack, E. P. Potential applications for alternative medicine to treat obesity in an aging population. Altern.Med Rev 2008;13(1):34-42. View abstract.
Colker, C., Kalman, D., and Torina, G. Effects of Citrus aurantium extract, caffeine, and St. John's Wort on body fat loss, lipid levels, and mood states in overweight healthy adults. Curr Ther Res 1999;60:145-153.
Gougeon, R., Harrigan, K., Tremblay, J. F., Hedrei, P., Lamarche, M., and Morais, J. A. Increase in the thermic effect of food in women by adrenergic amines extracted from citrus aurantium. Obes.Res 2005;13(7):1187-1194. View abstract.
Gray, S. and Woolf, A. D. Citrus aurantium used for weight loss by an adolescent with anorexia nervosa. J Adolesc.Health 2005;37(5):414-415. View abstract.
Haller, C. A., Duan, M., Jacob, P., III, and Benowitz, N. Human pharmacology of a performance-enhancing dietary supplement under resting and exercise conditions. Br J Clin Pharmacol 2008;65(6):833-840. View abstract.
Hansen, D. K., Juliar, B. E., White, G. E., and Pellicore, L. S. Developmental toxicity of Citrus aurantium in rats. Birth Defects Res B Dev.Reprod.Toxicol. 2011;92(3):216-223. View abstract.
Higgins, J. P., Tuttle, T. D., and Higgins, C. L. Energy beverages: content and safety. Mayo Clin Proc. 2010;85(11):1033-1041. View abstract.
Kaats, G. R., Miller, H., Preuss, H. G., and Stohs, S. J. A 60day double-blind, placebo-controlled safety study involving Citrus aurantium (bitter orange) extract. Food Chem Toxicol. 2013;55:358-362. View abstract.
Lynch B. Review of the safety of p-synephrine and caffeine. Intertek-Cantox Report, 2013;1-20.
Preuss, H. G., DiFerdinando, D., Bagchi, M., and Bagchi, D. Citrus aurantium as a thermogenic, weight-reduction replacement for ephedra: an overview. J.Med. 2002;33(1-4):247-264. View abstract.
Seifert, J. G., Nelson, A., Devonish, J., Burke, E. R., and Stohs, S. J. Effect of acute administration of an herbal preparation on blood pressure and heart rate in humans. Int J Med Sci 2011;8(3):192-197. View abstract.
Shara M, Stohs SJ. Safety evaluation of Bitter orange extract (p-synephrine) in healthy volunteers. J.Amer.Coll.Nutr. 2011;30:358.
Stohs, S. J., Preuss, H. G., and Shara, M. A review of the human clinical studies involving Citrus aurantium (bitter orange) extract and its primary protoalkaloid p-synephrine. Int J Med Sci 2012;9(7):527-538. View abstract.
Stohs, S. J., Preuss, H. G., Keith, S. C., Keith, P. L., Miller, H., and Kaats, G. R. Effects of p-synephrine alone and in combination with selected bioflavonoids on resting metabolism, blood pressure, heart rate and self-reported mood changes. Int J Med Sci 2011;8(4):295-301. View abstract.
Thomas, J. E., Munir, J. A., McIntyre, P. Z., and Ferguson, M. A. STEMI in a 24-year-old man after use of a synephrine-containing dietary supplement: a case report and review of the literature. Tex.Heart Inst.J 2009;36(6):586-590. View abstract.
Wu, H., Jing, Z., Tang, X., Wang, X., Zhang, S., Yu, Y., Wang, Z., Cao, H., Huang, L., Yu, Y., and Wang, Y. To compare the efficacy of two kinds of Zhizhu pills in the treatment of functional dyspepsia of spleen-deficiency and qi-stagnation syndrome: a randomized group sequential comparative trial. BMC.Gastroenterol 2011;11:81. View abstract.
Xu, L., Jiang, J., and Du, F. Z. [Application of dannang recipe no. 2 in the perioperative stage of laparoscopic cholecystectomy]. Zhongguo Zhong.Xi.Yi Jie.He.Za Zhi 2008;28(12):1090-1092. View abstract.
Zhou, L., Hao, R., and Jiang, L. [Clinical study on retarding aging effect of tongbu recipe to traditional Chinese medicine]. Zhongguo Zhong.Xi.Yi.Jie.He.Za Zhi. 1999;19(4):218-220. View abstract.
Allison DB, Cutter G, Poehlman ET, et al. Exactly which synephrine alkaloids does Citrus aurantium (bitter orange) contain? Int J Obes Relat Metab Disord 2005;29:443-6. View abstract.
Andrew R, Best SA, Watson DG, et al. Analysis of biogenic amines in plasma of hypertensive patients and a control group. Neurochem Res 1993;18:1179-82. View abstract.
Blumenthal M, Goldberg A, Brinckmann J, eds. Herbal Medicine Expanded Commission E Monographs. Newton, MA: Integrative Medicine Communications, 2000.
Bouchard NC, Howland MA, Greller HA, et al. Ischemic stroke associated with use of an ephedra-free dietary supplement containing synephrine. Mayo Clin Proc 2005;80:541-5. View abstract.
Buckle J. Use of aromatherapy as a complementary treatment for chronic pain. Altern Ther Health Med 1999;5:42-51. View abstract.
Bui LT, Nguyen DT, Ambrose PJ. Blood pressure and heart rate effects following a single dose of bitter orange. Ann Pharmacother 2006;40:53-7. View abstract.
Burke J, Seda G, Allen D, Knee TS. A case of severe exercise-induced rhabdomyolysis associated with a weight loss dietary supplement. Mil Med 2007;172:656-8. View abstract.
Calapai G, Firenzuoli F, Saitta A, et al. Antiobesity and cardiovascular toxic effects of Citrus aurantium extracts in the rat: A preliminary report. Fitoterapia 1999;70:586-92.
Carnat A, Carnat AP, Fraisse D, Lamaison JL. [Standardization of the sour orange flower and leaf]. Ann Pharm Fr 1999;57:410-4. View abstract.
Caron MF, Hotsko AL, Robertson S, et al. Electrocardiographic and hemodynamic effects of Panax ginseng. Ann Pharmacother 2002;36:758-63.. View abstract.
Colker CM, Kalman DS, Torina GC, et al. Effects of Citrus aurantium extract, caffeine, and St. John's wort on body fat loss, lipid levels, and mood states in overweight healthy adults. Curr Ther Res 1999;60:145-153.
D'Andrea G, Terrazzino S, Leon A, et al. Elevated levels of circulating trace amines in primary headaches. Neurology 2004;62:1701-5. View abstract.
Di Marco MP, Edwards DJ, Wainer IW, Ducharme MP. The effect of grapefruit juice and seville orange juice on the pharmacokinetics of dextromethorphan: the role of gut CYP3A and P-glycoprotein. Life Sci 2002;71:1149-60. View abstract.
Dragull K, Breksa AP 3rd, Cain B. Synephrine content of juice from Satsuma mandarins (Citrus unshiu Marcovitch). J Agric Food Chem 2008;56(19):8874-8. View abstract.
Edwards DJ, Fitzsimmons ME, Schuetz EG, et al. 6',7'-Dihydroxybergamottin in grapefruit juice and Seville orange juice: effects on cyclosporine disposition, enterocyte CYP3A4, and P-glycoprotein. Clin Pharmacol Ther 1999;65:237-44. View abstract.
Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
Firenzuoli F, Gori L, Galapai C. Adverse reaction to an adrenergic herbal extract (Citrus aurantium). Phytomedicine 2005;12:247-8. View abstract.
Fugh-Berman A, Myers A. Citrus aurantium, an ingredient of dietary supplements marketed for weight loss: Current status of clinical and basic Research. Exp Biol Med 2004;229:698-704. View abstract.
Gange CA, Madias C, Felix-Getzik EM, et al. Variant angina associated with bitter orange in a dietary supplement. Mayo Clin Proc 2006;81:545-8. View abstract.
Gray SG, Clair AA. Influence of aromatherapy on medication administration to residential-care residents with dementia and behavioral challenges. Am J Alzheimers Dis Other Demen 2002;17(3):169-74. View abstract.
Greenway F, de Jonge-Levitan L, Martin C, et al. Dietary herbal supplements with phenylephrine for weight loss. J Med Food 2006;9:572-8. View abstract.
Haller CA, Benowitz NL, Jacob P 3rd. Hemodynamic effects of ephedra-free weight-loss supplements in humans. Am J Med 2005;118:998-1003.. View abstract.
Health Canada. Synephrine, Octopamine and Caffeine Health Risk Assessment (HRA) Report. Approved May 16, 2011. Accessed May 25, 2016. Available at: http://www.nutratechinc.com/advz/Studies2011/Safety/S1%20Health%20Canada%200511.pdf.
Hu JF. [Inhibitory effects of Phyllanthus emblica juice on formation of N-nitrosomorpholine in vitro and N-nitrosoproline in rat and human]. Chung Hua Yu Fang I Hsueh Tsa Chih 1990;24:132-5. View abstract.
Huang YT, Wang GF, Chen CF, et al. Fructus aurantii reduced portal pressure in portal hypertensive rats. Life Sci 1995;57:2011-20. View abstract.
Ishiwa J, Sato T, Mimaki Y, et al. A citrus flavonoid, nobiletin, suppresses production and gene expression of matrix metalloproteinase 9/gelatinase B in rabbit synovial fibroblasts. J Rheumatol 2000;27:20-5. View abstract.
Jordan S, Murty M, Pilon K. Products containing bitter orange or synephrine: suspected cardiovascular adverse reactions. Canadian Adverse Reaction Newsletter 2004;14:3-4.
Keogh AM, Baron DW. Sympathomimetic abuse and coronary artery spasm. Br Med J 1985;291:940.
Kim DH, Song MJ, Bae EA, Han MJ. Inhibitory effect of herbal medicines on rotavirus infectivity. Biol Pharm Bull 2000;23:356-8. View abstract.
Kim KW, Kim HD, Jung JS, et al. Characterization of antidepressant-like effects of p-synephrine stereoisomers. Naunyn Schmiedebergs Arch Pharmacol 2001;364:21-6. View abstract.
Liu Y, Santillo MF. Cytochrome P450 2D6 and 3A4 enzyme inhibition by amine stimulants in dietary supplements. Drug Test Anal. 2016;8(3-4):307-10. View abstract.
Lopez HL, Ziegenfuss TN, Hofheins JE, et al. Eight weeks of supplementation with a multi-ingredient weight loss product enhances body composition, reduces hip and waist girth, and increases energy levels in overweight men and women. J Int Soc Sports Nut 2013;10(1):22. View abstract.
Malhotra S, Bailey DG, Paine MF, Watkins PB. Seville orange juice-felodipine interaction: comparison with dilute grapefruit juice and involvement of furocoumarins. Clin Pharmacol Ther 2001;69:14-23. View abstract.
Martin KW, Ernst E. Herbal medicines for treatment of fungal infections: a systematic review of controlled clinical trials. Mycoses 2004;47:87-92. View abstract.
McBride BF, Karapanos AK, Krudysz A, et al. Electrocardiographic and hemodynamic effects of a multicomponent dietary supplement containing ephedra and caffeine: a randomized controlled trial. JAMA 2004;291:216-21. View abstract.
Min B, Cios D, Kluger J, White CM. Absence of QTc-interval-prolonging or hemodynamic effects of a single dose of bitter-orange extract in healthy subjects. Pharmacotherapy 2005;25:1719-24. View abstract.
Mwaiko GL. Citrus peel oil extracts as mosquito larvae insecticides. East Afr Med J 1992;69:223-6. View abstract.
Naganuma M, Hirose S, Nakayama Y, et al. A study of the phototoxicity of lemon oil. Arch Dermatol Res 1985;278:31-6. . View abstract.
Nasir JM, Durning SJ, Ferguson M, et al. Exercise-induced syncope associated with QT prolongation and ephedra-free Xenadrine. Mayo Clin Proc 2004;79:1059-62.. View abstract.
National Collegiate Athletic Association. NCAA Banned-Drug Classes 2005-2006. Available at: http://www1.ncaa.org/membership/ed_outreach/health-safety/drug_testing/banned_drug_classes.pdf.
Nykamp DL, Fackih MN, Compton AL. Possible association of acute lateral-wall myocardial infarction and bitter orange supplement. Ann Pharmacother 2004;38:812-6. View abstract.
Pellati F, Benvenuti S, Melegari M, Firenzuoli F. Determination of adrenergic agonists from extracts and herbal products of Citrus aurantium L. var. amara by LC. J Pharm Biomed Anal 2002;29:1113-9. . View abstract.
Penzak SR, Acosta EP, Turner M, et al. Effect of Seville orange juice and grapefruit juice on indinavir pharmacokinetics. J Clin Pharmacol 2002;42:1165-70. View abstract.
Penzak SR, Jann MW, Cold JA, et al. Seville (sour) orange juice: synephrine content and cardiovascular effects in normotensive adults. J Clin Pharmacol 2001;41:1059-63. View abstract.
Ramadan W, Mourad B, Ibrahim S, Sonbol F. Oil of bitter orange: new topical antifungal agent. Int J Dermatol 1996;35:448-9. View abstract.
Sale C, Harris RC, Delves S, Corbett J. Metabolic and physiologic effects of ingesting extracts of bitter orange, green tea and guarana at rest and during treadmill walking in overweight males. Int J Obes (Lond) 2006;30(5):764-73. View abstract.
Satoh Y, Tashiro S, Satoh M, et al. [Studies on the bioactive constituents of Aurantii Fructus Immaturus]. Yakugaku Zasshi 1996;116:244-50. View abstract.
Shara M, Stohs SJ, Mukattash TL. Cardiovascular safety of oral p-synephrine (bitter orange) in healthy subjects: a randomized placebo-controlled cross-over clinical trial. Phytother Res. 2016;30(5):842-7. View abstract.
Smith TB, Staub BA, Natarajan GM, et al. Acute myocardial infarction associated with dietary supplements containing 1,3-dimethylamylamine and Citrus aurantium. Tex Heart Inst J 2014;41(1):70-2. View abstract.
Song DK, Suh HW, Jung JS, et al. Antidepressant-like effects of p-synephrine in mouse models of immobility tests. Neurosci Lett 1996;214:107-10. View abstract.
Sultan S, Spector J, Mitchell RM. Ischemic colitis associated with use of a bitter orange-containing dietary weight-loss supplement. Mayo Clin Proc 2006;81:1630-1.. View abstract.
Suzuki O, Matsumoto T, Oya M, Katsumata Y. Oxidation of synephrine by type A and type B monoamine oxidase. Experientia 1979;35:1283-4. View abstract.
The Federal Institute for Risk Assessment (Bundesinstitut fur Risikobewertung - Germany). Health assessment of sports and weight loss products containing synephrine and caffeine. 2012. BfR Opinion No. 004/2012.
Uckoo RM, Jayaprakasha GK, Nelson SD, Patil BS. Rapid simultaneous determination of amines and organic acids in citrus using high-performance liquid chromatography. Talanta 2011;83(3):948-54. View abstract.
Vierck JL, Icenoggle DL, Bucci L, Dodson MV. The effects of ergogenic compounds on myogenic satellite cells. Med Sci Sports Exerc 2003;35:769-76. View abstract.
Visentin V, Morin N, Fontana E, et al. Dual action of octopamine on glucose transport into adipocytes: inhibition via beta3-adrenoceptor activation and stimulation via oxidation by amine oxidases. J Pharmacol Exp Ther 2001;299:96-104. View abstract.
Vitetta L, Thomsen M, Sali A. Black cohosh and other herbal remedies associated with acute hepatitis. Med J Aust 2003;178:411-2.. View abstract.
Zhao XW, Li JX, Zhu ZR, et al. Anti-shock effects of synthetic effective compositions of fructus aurantii immaturus. Experimental study and clinical observation. Chin Med J (Engl) 1989;102:91-3. View abstract.