Oolong Tea

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What other names is Oolong Tea known by?

Brown Tea, Camélia Chinois, Camellia sinensis, Camellia thea, Camellia theifera, Dragon Noir, EGCG, Epigallo Catechin Gallate, Epigallocatechin Gallate, Épigallocatéchine Gallate, Té Oolong, Tea, Tea Oolong, Thé Oolong, Thea bohea, Thea sinensis, Thea viridis, Theaflavin, Théaflavine, Wu Long, Wulong, Wu Long Tea, Wu-Long Tea, Wu Yi, Wuyi, Wuyi Oolong, Wuyi Tea, Wu Yi Wulong Tea.

What is Oolong Tea?

Oolong tea is a product made from the leaves, buds, and stems of the Camellia sinensis plant. This is the same plant that is also used to make black tea and green tea. The difference is in the processing. Oolong tea is partially fermented, black tea is fully fermented, and green tea is unfermented.

Oolong tea is used to sharpen thinking skills and improve mental alertness. It is also used to prevent cancer, tooth decay, osteoporosis, and heart disease.

Some people use oolong tea to treat obesity, diabetes, "hardening of the arteries" (atherosclerosis), high cholesterol and skin allergies such as eczema; and to boost the immune system.

Likely Effective for...

  • Mental alertness. Drinking oolong tea or other caffeinated beverages throughout the day seems to maintain alertness and mental performance. Combining caffeine with sugar as an "energy drink" seems to improve mental performance better than either caffeine or sugar alone.

Possibly Effective for...

  • Preventing ovarian cancer. Women who regularly drink tea, including black tea, green tea, or oolong tea, appear to have a significantly lower risk of developing ovarian cancer. One study found that drinking 2 or more cups of tea daily seems to cut ovarian cancer risk by almost half.

Insufficient Evidence to Rate Effectiveness for...

  • Treating skin allergies (eczema). Developing research suggests that drinking about 4 cups (34 oz or 1000 mL) of oolong tea per day in 3 divided doses improves eczema that hasn't responded to other treatments. It may take 1 or 2 weeks of treatment to see improvement.
  • Treating diabetes. Some research suggests that drinking about 6 cups (50 oz or 1500 mL) of oolong tea for 30 days might lower blood sugar in people with type 2 diabetes. However, tea drinking doesn't seem to prevent diabetes.
  • Preventing high blood pressure. Some research in Chinese people shows that drinking 1 or 2 cups (4-20 oz or 120-599 mL) of oolong tea or green tea daily seems to prevent high blood pressure. Drinking more tea seems to lower the risk even more.
  • Weak bones (osteoporosis). There is some evidence that drinking oolong tea for 10 years is associated with stronger bones (increased bone mineral density).
  • Promoting weight loss.
  • Preventing tooth decay.
  • Reducing the risk of cancer.
  • Other conditions.
More evidence is needed to rate the effectiveness of oolong tea for these uses.

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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How does Oolong Tea work?

Oolong tea contains caffeine. Caffeine works by stimulating the central nervous system (CNS), heart, and muscles. Oolong tea also contains theophylline and theobromine, which are chemicals similar to caffeine.

Are there safety concerns?

Too much oolong tea, more than five cups per day, can cause side effects because of the caffeine. 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, convulsions, and confusion.

Special Precautions & Warnings:

Pregnancy and breast-feeding: If you are pregnant or breast-feeding, oolong tea in small amounts is probably not harmful. However, do not drink more than 2 cups a day of oolong tea. That amount of tea contains about 200 mg of caffeine. Too much caffeine during pregnancy might cause premature delivery, low birth weight, and harm to the baby. Too much caffeine during breast-feeding might cause irritability and increase bowel movements in nursing infants.

Children: Caffeine is probably safe in children in amounts commonly found in foods.

Anxiety disorders: The caffeine in oolong tea might make anxiety disorders worse.

Bleeding disorders: Some research suggests that caffeine might slow blood clotting. Though this research was not done in humans, there is still some concern that caffeine might make bleeding disorders worse.

Heart conditions: Caffeine in oolong tea can cause irregular heartbeat in some people.

Diabetes: Some research suggests that the caffeine in oolong tea may affect the way people with diabetes process sugar and may complicate blood sugar control. Caffeine has been reported to both increase and decrease blood sugar. There is also some interesting research that suggests caffeine may make the warning signs of low blood sugar in people with type 1 diabetes more noticeable. This might increase the ability of people with diabetes to detect and treat low blood sugar. However, the downside is that caffeine might actually increase the number of low-sugar episodes. If you have diabetes, talk with your healthcare provider before using oolong tea.

Diarrhea. Oolong tea contains caffeine. The caffeine in oolong tea, especially when taken in large amounts, can worsen diarrhea.

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.

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.

Weak bones (osteoporosis): Drinking oolong tea can flush out calcium in the urine. That can affect bone health. If you have osteoporosis, don't drink more than 3 cups of oolong tea per day. Consider taking calcium supplements to make up for the calcium that is flushed out. If you have a genetic condition that harms the way your body processes vitamin D, get medical advice before consuming a lot of caffeine.

Are there any interactions with medications?



Amphetamines
Interaction Rating: Major Do not take this combination.

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
Interaction Rating: Major Do not take this combination.

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
Interaction Rating: Major Do not take this combination.

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. This could lead to serious side effects and heart problems. Do not take caffeine-containing products and ephedrine at the same time.



Adenosine (Adenocard)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

Oolong tea contains caffeine. The caffeine in oolong tea might block the effects 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)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

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)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

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)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

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)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

Oolong tea contains caffeine. The caffeine in oolong tea might block the effects 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)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

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
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

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)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

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
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

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 for asthma (Beta-adrenergic agonists)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

Oolong tea contains caffeine. Caffeine can stimulate the heart. Some medications for asthma can also stimulate the heart. Taking caffeine with some medications for asthma might cause too much stimulation and cause heart problems.

Some medications for asthma include albuterol (Proventil, Ventolin, Volmax), metaproterenol (Alupent), terbutaline (Bricanyl, Brethine), and isoproterenol (Isuprel).



Medications for depression (MAOIs)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

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.



Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

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.



Nicotine
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

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)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

The stimulant effects of the caffeine in oolong tea can block the sleep-producing effects of pentobarbital.



Phenylpropanolamine
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

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)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

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
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

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)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

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.



Alcohol
Interaction Rating: Minor Be cautious with this combination.
Talk with your health provider.

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)
Interaction Rating: Minor Be cautious with this combination.
Talk with your health provider.

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)
Interaction Rating: Minor Be cautious with this combination.
Talk with your health provider.

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)
Interaction Rating: Minor Be cautious with this combination.
Talk with your health provider.

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)
Interaction Rating: Minor Be cautious with this combination.
Talk with your health provider.

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)
Interaction Rating: Minor Be cautious with this combination.
Talk with your health provider.

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.

Dosing considerations for Oolong Tea.

The following doses have been studied in scientific research:

BY MOUTH:

Doses of oolong tea vary significantly, but usually range between 1-10 cups daily.
  • For headache or restoring mental alertness: The typical dose of caffeine is up to 250 mg (about 5 cups of oolong tea) per day. Oolong tea contains 50-60 mg caffeine per cup.
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Reviewed on 3/29/2011 12:35:40 PM

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