OOLONG TEA: Overview, Uses, Side Effects, Precautions, Interactions, Dosing and Reviews

Overview

Oolong tea is made from the Camellia sinensis plant. Its dried leaves and leaf buds are used to make several different teas, including black and green teas.

Oolong tea is fermented for longer than green tea, but less than black tea. It contains caffeine which affects thinking and alertness. Caffeine works by stimulating the central nervous system, heart, and muscles.

People use oolong tea for mental alertness. It is also used for obesity, diabetes, high blood pressure, autism, and many other conditions, but there is no good scientific evidence to support these other uses.

Don't confuse oolong tea with other caffeine sources, including coffee, black tea, and green tea. These are not the same.

Uses & Effectiveness

Likely Effective for

Mental alertness. Drinking oolong tea or other caffeinated beverages throughout the day seems to help maintain alertness and mental performance.

There is interest in using oolong tea for a number of other purposes, but there isn't enough reliable information to say whether it might be helpful.

Side Effects

When taken by mouth: Oolong tea is commonly consumed as a beverage. Drinking oolong tea in moderate amounts (about 4 cups daily) is likely safe for most people.

Drinking more than 4 cups of oolong tea daily is possibly unsafe. Drinking large amounts might cause side effects due to the caffeine content. These side effects can range from mild to serious and include headache and irregular heartbeat.

Special Precautions and Warnings

Pregnancy: Drinking moderate amounts of oolong tea during pregnancy is possibly safe. Do not drink more than 3 cups of oolong tea daily. This provides about 300 mg of caffeine. Consuming more than this during pregnancy is possibly unsafe and has been linked to an increased risk of miscarriage, increased risk of sudden infant death syndrome (SIDS), and other negative effects, including symptoms of caffeine withdrawal in newborns and lower birth weight.

Breast-feeding: Drinking moderate amounts of oolong tea while breast-feeding is possibly safe. But drinking more than 3 cups of oolong tea daily is possibly unsafe. The caffeine in oolong tea is passed into breastmilk. It might cause irritability and increased bowel movements in nursing infants.

Children: Oolong tea is possibly safe in children when consumed in amounts found in food and beverages.

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

Bleeding disorders: Oolong tea contains caffeine. Caffeine might slow blood clotting. Use caffeine cautiously if you have a bleeding disorder.

Heart problems: Oolong tea contains caffeine. Caffeine can cause irregular heartbeat in certain people. If you have a heart condition, use caffeine with caution.

Diabetes: Oolong tea contains caffeine. Caffeine might affect blood sugar levels. Use caffeine with caution if you have diabetes.

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

Seizures: Oolong tea contains caffeine. 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 products such as oolong tea.

Glaucoma: Oolong tea contains caffeine. Caffeine can increase the pressure inside the eye. The increase occurs within 30 minutes and lasts for at least 90 minutes.

High blood pressure: Oolong tea contains caffeine. Caffeine might increase blood pressure. But 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 daily. If you are generally healthy and get enough calcium from your food or supplements, drinking about 4 cups of oolong tea daily doesn't seem to increase the risk of getting osteoporosis.

Interactions

Major Interaction

Do not take this combination

Ephedrine interacts with OOLONG TEA
Oolong tea contains caffeine. Caffeine is a stimulant drug. Stimulant drugs speed up the nervous system. Ephedrine is also a stimulant drug. Taking oolong tea along with ephedrine might cause too much stimulation and sometimes serious side effects and heart problems.

Moderate Interaction

Be cautious with this combination

Adenosine (Adenocard) interacts with OOLONG TEA
Oolong tea contains caffeine. The caffeine in oolong tea might block the effects of adenosine, which is used to do a test called a cardiac stress test. Stop consuming oolong tea or other caffeine-containing products at least 24 hours before a cardiac stress test.
Cimetidine (Tagamet) interacts with OOLONG TEA
Oolong tea contains caffeine. The body breaks down caffeine to get rid of it. Cimetidine can decrease how quickly the body breaks down caffeine. Taking cimetidine along with oolong tea might increase the risk of side effects from caffeine, such as jitteriness, headache, and fast heartbeat.
Clozapine (Clozaril) interacts with OOLONG TEA
The body breaks down clozapine to get rid of it. The caffeine in oolong tea seems to decrease how quickly the body breaks down clozapine. Taking oolong tea along with clozapine can increase the effects and side effects of clozapine.
Dipyridamole (Persantine) interacts with OOLONG TEA
Oolong tea contains caffeine. The caffeine in oolong tea might block the effects of dipyridamole. Dipyridamole is often used by doctors to do a test on the heart 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
Oolong tea contains caffeine. The body breaks down caffeine to get rid of it. Disulfiram can decrease how quickly the body gets rid of caffeine. Taking oolong tea along with disulfiram might increase the risk of side effects from caffeine, such as jitteriness, headache, and fast heartbeat.
Estrogens interacts with OOLONG TEA
Oolong tea contains caffeine. The body breaks down caffeine to get rid of it. Estrogens can decrease how quickly the body breaks down caffeine. Taking estrogen and drinking oolong tea can increase the risk of side effects from caffeine, such as jitteriness, headache, and fast heartbeat.
Fluvoxamine (Luvox) interacts with OOLONG TEA
Oolong tea contains caffeine. The body breaks down caffeine to get rid of it. Fluvoxamine can decrease how quickly the body breaks down caffeine. Taking oolong tea along with fluvoxamine might increase the risk of side effects from caffeine, such as jitteriness, headache, and fast heartbeat.
Lithium interacts with OOLONG TEA
The caffeine in oolong tea can increase how quickly the body gets rid of lithium. If you take products that contain caffeine and you also take lithium, do not stop taking caffeine all at once. Stopping caffeine too quickly can increase the side effects of lithium.
Medications for depression (MAOIs) interacts with OOLONG TEA
Oolong tea contains caffeine. There is some concern that caffeine can interact with certain medications, called MAOIs. If caffeine is taken with these medications, it might increase the risk for serious side effects including fast heartbeat and very high blood pressure.

Some common MAOIs include phenelzine (Nardil), selegiline (Zelapar), and tranylcypromine (Parnate).
Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs) interacts with OOLONG TEA
Oolong tea might slow blood clotting. Taking oolong tea along with medications that also slow blood clotting might increase the risk of bruising and bleeding.
Nicotine interacts with OOLONG TEA
Oolong tea contains caffeine. Caffeine can stimulate the heart. Nicotine can also stimulate the heart. Taking oolong tea with nicotine might cause too much stimulation and cause heart problems, such as increased heart rate or blood pressure.
Pentobarbital (Nembutal) interacts with OOLONG TEA
Oolong tea contains caffeine. The stimulant effects of caffeine 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 caffeine along with phenylpropanolamine might cause too much stimulation and increase the risk of a fast heartbeat, high blood pressure, and nervousness.
Riluzole (Rilutek) interacts with OOLONG TEA
Drinking oolong tea might decrease how quickly the body breaks down riluzole. This might 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. This might increase the effects and side effects of theophylline.
Verapamil (Calan, others) interacts with OOLONG TEA
Oolong tea contains caffeine. Verapamil can decrease how quickly the body gets rid of caffeine. Taking caffeine along with verapamil can increase the risk of caffeine side effects including jitteriness, headache, and fast heartbeat.
Medications for asthma (Beta-adrenergic agonists) interacts with OOLONG TEA
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.
Stimulant drugs interacts with OOLONG TEA
Stimulants, such as amphetamines and cocaine, speed up the nervous system. By speeding up the nervous system, stimulant medications can increase blood pressure and speed up the heartbeat. Oolong tea contains caffeine. Caffeine can 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.
Pioglitazone (Actos) interacts with OOLONG TEA
Oolong tea contains caffeine. Caffeine might increase the amount of pioglitazone that the body absorbs. Taking caffeine might increase the effects and adverse effects of pioglitazone.

Minor Interaction

Be watchful with this combination

Alcohol (Ethanol) interacts with OOLONG TEA
Oolong tea contains caffeine. 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 increase the risk for side effects from caffeine, including jitteriness, headache, and fast heartbeat.
Antibiotics (Quinolone antibiotics) interacts with OOLONG TEA
Oolong tea contains caffeine. 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 for side effects from caffeine, such as jitteriness, headache, and fast heartbeat.
Birth control pills (Contraceptive drugs) interacts with OOLONG TEA
Oolong tea contains caffeine. The body breaks down caffeine to get rid of it. Birth control pills can decrease how quickly the body breaks down caffeine. This might increase the risk for side effects from caffeine, such as jitteriness, headache, and fast heartbeat.
Fluconazole (Diflucan) interacts with OOLONG TEA
Oolong tea contains caffeine. The body breaks down caffeine to get rid of it. Fluconazole might decrease how quickly the body gets rid of caffeine. Taking oolong tea along with fluconazole might increase the risk of side effects from caffeine, such as jitteriness, headache, and fast heartbeat.
Medications for diabetes (Antidiabetes drugs) interacts with OOLONG TEA
Oolong tea contains caffeine. Caffeine can either increase or decrease blood sugar. Diabetes medications are used to lower blood sugar. Taking some medications for diabetes along with caffeine might change the effects of the diabetes medications. Monitor your blood sugar closely. The dose of your diabetes medication might need to be changed.
Mexiletine (Mexitil) interacts with OOLONG TEA
Oolong tea contains caffeine. The body breaks down caffeine to get rid of it. Mexiletine can decrease how quickly the body breaks down caffeine. Taking mexiletine along with oolong tea might increase the risk of side effects from caffeine, such as jitteriness, headache, and fast heartbeat.
Terbinafine (Lamisil) interacts with OOLONG TEA
Oolong tea contains caffeine. Terbinafine can decrease how quickly the body gets rid of caffeine. Taking terbinafine with oolong tea might increase the risk of side effects from caffeine, such as jitteriness, headache, and fast heartbeat.

Dosing

Oolong tea is commonly consumed by adults as a beverage, typically in amounts of 1-4 cups daily. Speak with a healthcare provider to find out what dose might be best for a specific condition.

View References

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What Are Bruises? And What Causes Them?

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Oolong Tea - Uses, Side Effects, and More

Overview

Uses & Effectiveness

Likely Effective for

Side Effects

Special Precautions and Warnings

Interactions

Major Interaction

Ephedrine interacts with OOLONG TEA

Moderate Interaction

Adenosine (Adenocard) interacts with OOLONG TEA

Cimetidine (Tagamet) interacts with OOLONG TEA

Clozapine (Clozaril) interacts with OOLONG TEA

Dipyridamole (Persantine) interacts with OOLONG TEA

Disulfiram (Antabuse) interacts with OOLONG TEA

Estrogens interacts with OOLONG TEA

Fluvoxamine (Luvox) interacts with OOLONG TEA

Lithium interacts with OOLONG TEA

Medications for depression (MAOIs) interacts with OOLONG TEA

Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs) interacts with OOLONG TEA

Nicotine interacts with OOLONG TEA

Pentobarbital (Nembutal) interacts with OOLONG TEA

Phenylpropanolamine interacts with OOLONG TEA

Riluzole (Rilutek) interacts with OOLONG TEA

Theophylline interacts with OOLONG TEA

Verapamil (Calan, others) interacts with OOLONG TEA

Medications for asthma (Beta-adrenergic agonists) interacts with OOLONG TEA

Stimulant drugs interacts with OOLONG TEA

Pioglitazone (Actos) interacts with OOLONG TEA

Minor Interaction

Alcohol (Ethanol) interacts with OOLONG TEA

Antibiotics (Quinolone antibiotics) interacts with OOLONG TEA

Birth control pills (Contraceptive drugs) interacts with OOLONG TEA

Fluconazole (Diflucan) interacts with OOLONG TEA

Medications for diabetes (Antidiabetes drugs) interacts with OOLONG TEA

Mexiletine (Mexitil) interacts with OOLONG TEA

Terbinafine (Lamisil) interacts with OOLONG TEA

Dosing

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