Oolong tea is used to improve mental alertness. It is also used for obesity and heart disease, to prevent weak and brittle bones (osteoporosis), and for other conditions, but there is no good scientific evidence to support these other uses.
How does it work ?
Uses & Effectiveness ?
Likely Effective for
Insufficient Evidence for
- Eczema (atopic dermatitis). Early research suggests that drinking oolong tea might improve symptoms of eczema in some people. It may take 1 or 2 weeks of treatment to see improvement.
- Autism. Early research shows that drinking oolong tea might help to improve some symptoms of autism.
- Diabetes. Some research suggests that drinking oolong tea for 30 days might lower blood sugar in people with type 2 diabetes. However, tea drinking doesn't seem to prevent diabetes.
- Menstrual cramps (dysmenorrhea). Drinking oolong tea doesn't seem to help reduce menstrual cramps.
- High blood pressure. Some research in Chinese people suggests that drinking oolong tea or green tea daily prevents developing high blood pressure. Drinking more tea seems to lower the risk even more.
- Obesity. Early research suggests that drinking oolong tea does not decrease body weight in overweight or obese people.
- Weak and brittle bones (osteoporosis). There is some evidence that drinking oolong tea for 10 years is linked with having stronger bones (increased bone mineral density).
- Ovarian cancer. Women who regularly drink tea, including black tea, green tea, or oolong tea, appear to have a lower risk for ovarian cancer when compared with women who never or rarely drink tea.
- Rotting Teeth.
- Other conditions.
Drinking oolong tea is POSSIBLY UNSAFE when consumed for a long time or in high doses (more than 4 cups per day). Drinking large amounts of oolong tea might cause side effects due to the caffeine content. These side effects can range from mild to serious and include headache, nervousness, sleep problems, vomiting, diarrhea, irritability, irregular heartbeat, tremor, heartburn, dizziness, ringing in the ears, seizures (convulsions), and confusion. Also, people who drink a lot of oolong tea every day may need to drink more tea to get the same effects. They may also become "dependent" on tea to the point that they develop withdrawal symptoms if they suddenly stop drinking it.
Special Precautions and Warnings
Children: Oolong tea is POSSIBLY SAFE when taken by mouth by children in amounts commonly found in foods.
Anxiety disorders: The caffeine in oolong tea might make anxiety disorders worse.
Bleeding disorders: There is some reason to believe that the caffeine in oolong tea might slow blood clotting, though this hasn't been shown in people. Use caffeine cautiously if you have a bleeding disorder.
Heart problems: Caffeine in oolong tea can cause irregular heartbeat in certain people. If you have a heart condition, use caffeine with caution.
Diabetes: The caffeine in oolong day might affect blood sugar levels. Use oolong tea with caution if you have diabetes.
Diarrhea: Oolong tea contains caffeine. The caffeine in oolong tea, especially when taken in large amounts, can worsen diarrhea.
Seizures: Oolong tea contains caffeine. There is a concern that high doses of caffeine might cause seizures or decrease the effects of drugs used to prevent seizures. If you have ever had a seizure, don't use high doses of caffeine or caffeine-containing supplements such as oolong tea.
Glaucoma: The caffeine in oolong tea increases the pressure inside the eye. The increase occurs within 30 minutes and lasts for at least 90 minutes.
High blood pressure: The caffeine in oolong tea might increase blood pressure in people with high blood pressure. However, this doesn't seem to happen in people who regularly drink oolong tea or other caffeinated products.
Irritable bowel syndrome (IBS): Oolong tea contains caffeine. The caffeine in oolong tea, especially when taken in large amounts, can worsen diarrhea and might worsen symptoms of IBS.
Brittle bones (osteoporosis): Drinking oolong tea can increase the amount of calcium that is flushed out in the urine. This might weaken bones. If you have osteoporosis, don't drink more than 3 cups of oolong tea per day. If you are generally healthy and getting enough calcium from your food and supplements, taking up to 400 mg of caffeine daily (about 4 cups of oolong tea) doesn't seem to increase the risk of getting osteoporosis. Postmenopausal women who have an inherited condition that keeps them from processing vitamin D normally should be especially cautious when using caffeine.
Amphetamines interacts with OOLONG TEA
Stimulant drugs such as amphetamines speed up the nervous system. By speeding up the nervous system, stimulant medications can make you feel jittery and increase your heart rate. The caffeine in oolong tea might also speed up the nervous system. Taking oolong tea along with stimulant drugs might cause serious problems including increased heart rate and high blood pressure. Avoid taking stimulant drugs along with oolong tea.
Cocaine interacts with OOLONG TEA
Stimulant drugs such as cocaine speed up the nervous system. By speeding up the nervous system, stimulant medications can make you feel jittery and increase your heart rate. The caffeine in oolong tea might also speed up the nervous system. Taking oolong tea along with stimulant drugs might cause serious problems including increased heart rate and high blood pressure. Avoid taking stimulant drugs along with oolong tea.
Ephedrine interacts with OOLONG TEA
Stimulant drugs speed up the nervous system. Caffeine (contained in oolong tea) and ephedrine are both stimulant drugs. Taking caffeine along with ephedrine might cause too much stimulation and sometimes serious side effects and heart problems. Do not take caffeine-containing products and ephedrine at the same time.
Do not take this combination
Adenosine (Adenocard) interacts with OOLONG TEA
Oolong tea contains caffeine. The caffeine in oolong tea might block the affects of adenosine (Adenocard). Adenosine (Adenocard) is often used by doctors to do a test on the heart. This test is called a cardiac stress test. Stop consuming oolong tea or other caffeine-containing products at least 24 hours before a cardiac stress test.
Antibiotics (Quinolone antibiotics) interacts with OOLONG TEA
The body breaks down caffeine to get rid of it. Some antibiotics might decrease how quickly the body breaks down caffeine. Taking these antibiotics along with oolong tea can increase the risk of side effects including jitteriness, headache, increased heart rate, and other side effects.
Some antibiotics that decrease how quickly the body breaks down caffeine include ciprofloxacin (Cipro), enoxacin (Penetrex), norfloxacin (Chibroxin, Noroxin), sparfloxacin (Zagam), trovafloxacin (Trovan), and grepafloxacin (Raxar).
Cimetidine (Tagamet) interacts with OOLONG TEA
Oolong tea contains caffeine. The body breaks down caffeine to get rid of it. Cimetidine (Tagamet) can decrease how quickly your body breaks down caffeine. Taking cimetidine (Tagamet) along with oolong tea might increase the chance of caffeine side effects including jitteriness, headache, fast heartbeat, and others.
Clozapine (Clozaril) interacts with OOLONG TEA
The body breaks down clozapine (Clozaril) to get rid of it. The caffeine in oolong tea seems to decrease how quickly the body breaks down clozapine (Clozaril). Taking oolong tea along with clozapine (Clozaril) can increase the effects and side effects of clozapine (Clozaril).
Dipyridamole (Persantine) interacts with OOLONG TEA
Oolong tea contains caffeine. The caffeine in oolong tea might block the affects of dipyridamole (Persantine). Dipyridamole (Persantine) is often used by doctors to do a test on the heart. This test is called a cardiac stress test. Stop consuming oolong tea or other caffeine-containing products at least 24 hours before a cardiac stress test.
Disulfiram (Antabuse) interacts with OOLONG TEA
The body breaks down caffeine to get rid of it. Disulfiram (Antabuse) can decrease how quickly the body gets rid of caffeine. Taking oolong tea (which contains caffeine) along with disulfiram (Antabuse) might increase the effects and side effects of caffeine including jitteriness, hyperactivity, irritability, and others.
Estrogens interacts with OOLONG TEA
The body breaks down the caffeine in oolong tea to get rid of it. Estrogens can decrease how quickly the body breaks down caffeine. Taking oolong tea along with estrogens can cause jitteriness, headache, fast heartbeat, and other side effects. If you take estrogens limit your caffeine intake.
Some estrogen pills include conjugated equine estrogens (Premarin), ethinyl estradiol, estradiol, and others.
Fluvoxamine (Luvox) interacts with OOLONG TEA
The body breaks down the caffeine in oolong tea to get rid of it. Fluvoxamine (Luvox) can decrease how quickly the body breaks down caffeine. Taking oolong tea along with fluvoxamine (Luvox) might cause too much caffeine in the body, and increase the effects and side effects of caffeine.
Lithium interacts with OOLONG TEA
Your body naturally gets rid of lithium. The caffeine in oolong tea can increase how quickly your body gets rid of lithium. If you take products that contain caffeine and you take lithium, stop taking caffeine products slowly. Stopping oolong tea too quickly can increase the side effects of lithium.
Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs) interacts with OOLONG TEA
Oolong tea contains caffeine. Caffeine might slow blood clotting. Taking oolong tea along with medications that also slow clotting might increase the chances of bruising and bleeding.
Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), diclofenac (Voltaren, Cataflam, others), ibuprofen (Advil, Motrin, others), naproxen (Anaprox, Naprosyn, others), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, warfarin (Coumadin), and others.
Medications for depression (MAOIs) interacts with OOLONG TEA
Oolong tea contains caffeine. Caffeine can stimulate the body. Some medications used for depression can also stimulate the body. Taking oolong tea with these medications used for depression might cause serious side effects including fast heartbeat, high blood pressure, nervousness, and others.
Some of these medications used for depression include phenelzine (Nardil), tranylcypromine (Parnate), and others.
Nicotine interacts with OOLONG TEA
Stimulant drugs such as nicotine speed up the nervous system. By speeding up the nervous system, stimulant medications can make you feel jittery and increase your heart rate. The caffeine in oolong tea might also speed up the nervous system. Taking oolong tea along with stimulant drugs might cause serious problems including increased heart rate and high blood pressure. Avoid taking stimulant drugs along with caffeine.
Pentobarbital (Nembutal) interacts with OOLONG TEA
The stimulant effects of the caffeine in oolong tea can block the sleep-producing effects of pentobarbital.
Phenylpropanolamine interacts with OOLONG TEA
The caffeine in oolong tea can stimulate the body. Phenylpropanolamine can also stimulate the body. Taking oolong tea along with phenylpropanolamine might cause too much stimulation and increase heartbeat, blood pressure, and cause nervousness.
Riluzole (Rilutek) interacts with OOLONG TEA
The body breaks down riluzole (Rilutek) to get rid of it. Taking oolong tea can decrease how fast the body breaks down riluzole (Rilutek) and increase the effects and side effects of riluzole.
Theophylline interacts with OOLONG TEA
Oolong tea contains caffeine. Caffeine works similarly to theophylline. Caffeine can also decrease how quickly the body gets rid of theophylline. Taking oolong tea along with theophylline might increase the effects and side effects of theophylline.
Verapamil (Calan, Covera, Isoptin, Verelan) interacts with OOLONG TEA
The body breaks down the caffeine in oolong tea to get rid of it. Verapamil (Calan, Covera, Isoptin, Verelan) can decrease how quickly the body gets rid of caffeine. Taking oolong tea along with verapamil (Calan, Covera, Isoptin, Verelan) can increase the risk of caffeine side effects including jitteriness, headache, and an increased heartbeat.
Be cautious with this combination
Alcohol interacts with OOLONG TEA
The body breaks down the caffeine in oolong tea to get rid of it. Alcohol can decrease how quickly the body breaks down caffeine. Taking oolong tea along with alcohol might cause too much caffeine in the bloodstream and caffeine side effects including jitteriness, headache, and fast heartbeat.
Birth control pills (Contraceptive drugs) interacts with OOLONG TEA
The body breaks down the caffeine in oolong tea to get rid of it. Birth control pills can decrease how quickly the body breaks down caffeine. Taking oolong tea along with birth control pills can cause jitteriness, headache, fast heartbeat, and other side effects.
Some birth control pills include ethinyl estradiol and levonorgestrel (Triphasil), ethinyl estradiol and norethindrone (Ortho-Novum 1/35, Ortho-Novum 7/7/7), and others.
Fluconazole (Diflucan) interacts with OOLONG TEA
Oolong tea contains caffeine. The body breaks down caffeine to get rid of it. Fluconazole (Diflucan) might decrease how quickly the body gets rid of caffeine. Taking oolong tea along with fluconazole (Diflucan) might increase the risk of caffeine side effects such as nervousness, anxiety, and insomnia.
Medications for diabetes (Antidiabetes drugs) interacts with OOLONG TEA
Oolong tea might increase blood sugar. Diabetes medications are used to lower blood sugar. By increasing blood sugar, oolong tea might decrease the effectiveness of diabetes medications. 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, pioglitazone (Actos), rosiglitazone (Avandia), chlorpropamide (Diabinese), glipizide (Glucotrol), tolbutamide (Orinase), and others.
Mexiletine (Mexitil) interacts with OOLONG TEA
Oolong tea contains caffeine. The body breaks down caffeine to get rid of it. Mexiletine (Mexitil) can decrease how quickly the body breaks down caffeine. Taking mexiletine (Mexitil) along with oolong tea might increase the caffeine effects and side effects of oolong tea.
Terbinafine (Lamisil) interacts with OOLONG TEA
The body breaks down caffeine (contained in oolong tea) to get rid of it. Terbinafine (Lamisil) can decrease how fast the body gets rid of caffeine and increase the risk of side effects including jitteriness, headache, increased heartbeat, and other effects.
Be watchful with this combination
- For mental alertness: A single cup of tea containing 60 mg of caffeine has been used.
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