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.
Some people use bitter orange flower and its oil for general feebleness, "tired blood" (anemia), impurities of the skin, hair loss, cancer, frostbite, and as a tonic.
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.
How does it work?
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.
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.
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).
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.
There are reports that bitter orange can trigger headaches, including migraine and cluster headaches, in some people.
Bitter orange can cause sensitivity to the sun. Wear sunblock outside, especially if you are light-skinned.
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.
Glaucoma: Bitter orange might worsen glaucoma. Avoid using it if you have this condition.
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.
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.
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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