Suggested Dosing
1-10 cups PO qD; 1 tsp tea leaves/ 8 oz boiling water
Mental Alertness
1 cup or 60 mg caffeine (3 cups = 240-320 mg polyphenols)
Hyperlipidemia
>10 cups/day
Suggested Uses
Cancer (prevention), cognitive improvement, Crohn's disease, diuresis, genital warts, headaches, heart disease (prevention), Parkinson's disease (prevention), stomach disorders, weight loss (combination products), hypercholesterolemia
Efficacy
Possibly effective for listed uses
Studies show benefit in prevention of bladder, esophageal, pancreatic cancer; neg. results for stomach cancer
Interactions
Interaction Checker
No Results

Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor

Contraindicated (1)
- bortezomib
green tea decreases effects of bortezomib by Other (see comment). Contraindicated. Comment: Avoid green tea in patients being treated with bortezomib.
Serious - Use Alternative (0)
Monitor Closely (107)
- abciximab
green tea increases effects of abciximab by pharmacodynamic synergism. Use Caution/Monitor. (Theoretical interaction). Combination may increase risk of bleeding.
- adenosine
green tea decreases effects of adenosine by unspecified interaction mechanism. Use Caution/Monitor. (Theoretical interaction).
- albuterol
green tea increases effects of albuterol by pharmacodynamic synergism. Use Caution/Monitor. Due to caffeine content. Combination may increase CNS stimulatory effects due to caffeine in green tea.
- alteplase
green tea, alteplase. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- anagrelide
green tea increases effects of anagrelide by pharmacodynamic synergism. Use Caution/Monitor. (Theoretical interaction). Combination may increase risk of bleeding.
- antithrombin alfa
green tea, antithrombin alfa. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding, caution is advised.
- antithrombin III
green tea, antithrombin III. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding, caution is advised.
- arformoterol
green tea increases effects of arformoterol by pharmacodynamic synergism. Use Caution/Monitor. Due to caffeine content. Combination may increase CNS stimulatory effects due to caffeine in green tea.
- argatroban
green tea, argatroban. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding, caution is advised.
- aspirin
green tea increases effects of aspirin by pharmacodynamic synergism. Use Caution/Monitor. (Theoretical, due to caffeine content). Combination may increase risk of bleeding.
- aspirin rectal
green tea increases effects of aspirin rectal by pharmacodynamic synergism. Use Caution/Monitor. (Theoretical, due to caffeine content). Combination may increase risk of bleeding.
- aspirin/citric acid/sodium bicarbonate
green tea increases effects of aspirin/citric acid/sodium bicarbonate by pharmacodynamic synergism. Use Caution/Monitor. (Theoretical, due to caffeine content). Combination may increase risk of bleeding.
- benzphetamine
green tea, benzphetamine. Other (see comment). Use Caution/Monitor. Comment: Green tea may include caffeine. Caffeine is a CNS-stimulant and additive effects may be seen when coadministered with other CNS stimulants. Caffeine should be avoided or used cautiously.
- bivalirudin
green tea, bivalirudin. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding, caution is advised.
- caffeine
green tea increases effects of caffeine by Other (see comment). Use Caution/Monitor. Comment: Potential for increased risk of CNS stimulation due to caffeine component of green tea. Caution advised.
- cilostazol
green tea increases effects of cilostazol by pharmacodynamic synergism. Use Caution/Monitor. (Theoretical interaction). Combination may increase risk of bleeding.
- citalopram
green tea, citalopram. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- clopidogrel
green tea increases effects of clopidogrel by pharmacodynamic synergism. Use Caution/Monitor. (Theoretical interaction). Combination may increase risk of bleeding.
- clozapine
green tea decreases effects of clozapine by Other (see comment). Use Caution/Monitor. Comment: (Theoretical, due to caffeine content) High caffeine doses (400 1000mg/day) may increase levels/toxicity of clozapine. Clozapine clearance may decrease during coadministration of caffeine, and a documented increase in clozapine serum concentrations has occurred in selected patients. .
- dabigatran
green tea, dabigatran. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding, caution is advised.
- dalteparin
green tea, dalteparin. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding, caution is advised.
- darunavir
green tea, darunavir. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- dasatinib
green tea, dasatinib. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- deferasirox
green tea, deferasirox. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- desirudin
green tea, desirudin. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- dextroamphetamine
green tea, dextroamphetamine. Other (see comment). Use Caution/Monitor. Comment: Green tea may include caffeine. Caffeine is a CNS-stimulant and additive effects may be seen when coadministered with other CNS stimulants. Caffeine should be avoided or used cautiously.
- diclofenac
green tea, diclofenac. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- diethylpropion
green tea, diethylpropion. Other (see comment). Use Caution/Monitor. Comment: Green tea may include caffeine. Caffeine is a CNS-stimulant and additive effects may be seen when coadministered with other CNS stimulants. Caffeine should be avoided or used cautiously.
- diflunisal
green tea, diflunisal. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- dipyridamole
green tea increases effects of dipyridamole by pharmacodynamic synergism. Use Caution/Monitor. (Theoretical interaction). Dipyridamole is a platelet inhibitor and green tea has demonstrated antiplatelet effects in animals, it may be prudent to avoid the concomitant use of green tea with chronic dipyridamole therapy as the risk of bleeding may be increased.
- disulfiram
disulfiram increases levels of green tea by decreasing elimination. Use Caution/Monitor. Combination may increase caffeine levels. Caution should be taken due to increased risk of adverse effects due to caffeine in green tea.
- dobutamine
green tea increases effects of dobutamine by pharmacodynamic synergism. Use Caution/Monitor. Due to caffeine content. Combination may increase CNS stimulatory effects due to caffeine in green tea.
- dopamine
green tea increases effects of dopamine by pharmacodynamic synergism. Use Caution/Monitor. Combination may increase CNS stimulatory effects due to caffeine in green tea.
- duloxetine
green tea, duloxetine. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- enoxaparin
green tea, enoxaparin. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding, caution is advised.
- ephedrine
green tea increases effects of ephedrine by pharmacodynamic synergism. Use Caution/Monitor. Due to caffeine content. Combination may increase CNS stimulatory effects due to caffeine in green tea.
- epinephrine
green tea increases effects of epinephrine by pharmacodynamic synergism. Use Caution/Monitor. Due to caffeine content. Combination may increase CNS stimulatory effects due to caffeine in green tea.
- epinephrine racemic
green tea increases effects of epinephrine racemic by pharmacodynamic synergism. Use Caution/Monitor. Due to caffeine content. Combination may increase CNS stimulatory effects due to caffeine in green tea.
- eptifibatide
green tea increases effects of eptifibatide by pharmacodynamic synergism. Use Caution/Monitor. (Theoretical interaction). Combination may increase risk of bleeding.
- escitalopram
green tea, escitalopram. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- ethinylestradiol
ethinylestradiol increases levels of green tea by decreasing elimination. Use Caution/Monitor.
- etodolac
green tea, etodolac. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- fenoprofen
green tea, fenoprofen. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- ferric maltol
green tea, ferric maltol. Other (see comment). Use Caution/Monitor. Comment: When possible, do not consume green tea or green tea extract within 1 hour before or 2 hours after giving iron salts.
- ferrous fumarate
green tea, ferrous fumarate. Other (see comment). Use Caution/Monitor. Comment: When possible, do not consume green tea or green tea extract within 1 hour before or 2 hours after giving iron salts.
- ferrous sulfate
green tea, ferrous sulfate. Other (see comment). Use Caution/Monitor. Comment: When possible, do not consume green tea or green tea extract within 1 hour before or 2 hours after giving iron salts.
- fluoxetine
green tea, fluoxetine. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- flurbiprofen
green tea, flurbiprofen. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- fluvoxamine
green tea, fluvoxamine. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor.
- folic acid
green tea, folic acid. Other (see comment). Use Caution/Monitor. Comment: Concomitant consumption of green tea with folic acid is not recommended in pregnant women, megaloblastic anemia, or when a reduction in folic acid may have clinical consequences. A folate transporter interaction has been described, leading to decreases in bioavailability of folic acid.
- fondaparinux
green tea, fondaparinux. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding, caution is advised.
- fosphenytoin
fosphenytoin decreases levels of green tea by increasing metabolism. Use Caution/Monitor. Potential for decreased effects of caffeine in green tea. .
- heparin
green tea, heparin. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding, caution is advised.
- ibuprofen
green tea, ibuprofen. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- ibuprofen IV
green tea, ibuprofen IV. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- indomethacin
green tea, indomethacin. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- isocarboxazid
green tea, isocarboxazid. Other (see comment). Use Caution/Monitor. Comment: Avoid combination or excessive consumption of green tea. Combination may increase risk of cardiac arrhythmias or severe hypertension can occur due to caffeine component of green tea.
- isoniazid
green tea, isoniazid. Other (see comment). Use Caution/Monitor. Comment: Avoid combination or excessive consumption of green tea. Combination may increase risk of cardiac arrhythmias or severe hypertension can occur due to caffeine component of green tea.
- isoproterenol
green tea increases effects of isoproterenol by pharmacodynamic synergism. Use Caution/Monitor. Due to caffeine content. Combination may increase CNS stimulatory effects due to caffeine in green tea.
- ketoprofen
green tea, ketoprofen. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- ketorolac
green tea, ketorolac. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- levalbuterol
green tea increases effects of levalbuterol by pharmacodynamic synergism. Use Caution/Monitor. Due to caffeine content. Combination may increase CNS stimulatory effects due to caffeine in green tea.
- linezolid
green tea, linezolid. Other (see comment). Use Caution/Monitor. Comment: Avoid combination or excessive consumption of green tea. Combination may increase risk of cardiac arrhythmias or severe hypertension can occur due to caffeine component of green tea.
- lisdexamfetamine
green tea, lisdexamfetamine. Other (see comment). Use Caution/Monitor. Comment: Green tea may include caffeine. Caffeine is a CNS-stimulant and additive effects may be seen when coadministered with other CNS stimulants. Caffeine should be avoided or used cautiously.
- meclofenamate
green tea, meclofenamate. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- mefenamic acid
green tea, mefenamic acid. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- meloxicam
green tea, meloxicam. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- metaproterenol
green tea increases effects of metaproterenol by pharmacodynamic synergism. Use Caution/Monitor. Due to caffeine content. Combination may increase CNS stimulatory effects due to caffeine in green tea.
- methamphetamine
green tea, methamphetamine. Other (see comment). Use Caution/Monitor. Comment: Green tea may include caffeine. Caffeine is a CNS-stimulant and additive effects may be seen when coadministered with other CNS stimulants. Caffeine should be avoided or used cautiously.
- methylphenidate
green tea, methylphenidate. Other (see comment). Use Caution/Monitor. Comment: Green tea may include caffeine. Caffeine is a CNS-stimulant and additive effects may be seen when coadministered with other CNS stimulants. Caffeine should be avoided or used cautiously.
- mexiletine
mexiletine increases levels of green tea by decreasing elimination. Use Caution/Monitor. (Caffeine). Combination may increase caffeine levels. Caution should be taken in patients with cardiac arrhythmias. Avoid or limit intake of caffeine.
- milnacipran
green tea, milnacipran. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- modafinil
green tea, modafinil. Other (see comment). Use Caution/Monitor. Comment: Green tea may include caffeine. Caffeine is a CNS-stimulant and additive effects may be seen when coadministered with other CNS stimulants. Caffeine should be avoided or used cautiously.
- nabumetone
green tea, nabumetone. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- naproxen
green tea, naproxen. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- nicotine inhaled
green tea, nicotine inhaled. Other (see comment). Use Caution/Monitor. Comment: Green tea may include caffeine. Caffeine is a CNS-stimulant and additive effects may be seen when coadministered with other CNS stimulants. Caffeine should be avoided or used cautiously.
- nicotine intranasal
green tea, nicotine intranasal. Other (see comment). Use Caution/Monitor. Comment: Green tea may include caffeine. Caffeine is a CNS-stimulant and additive effects may be seen when coadministered with other CNS stimulants. Caffeine should be avoided or used cautiously.
- norepinephrine
green tea increases effects of norepinephrine by pharmacodynamic synergism. Use Caution/Monitor. Due to caffeine content. Combination may increase CNS stimulatory effects due to caffeine in green tea.
- oxaprozin
green tea, oxaprozin. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- paroxetine
green tea, paroxetine. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- phendimetrazine
green tea, phendimetrazine. Other (see comment). Use Caution/Monitor. Comment: Green tea may include caffeine. Caffeine is a CNS-stimulant and additive effects may be seen when coadministered with other CNS stimulants. Caffeine should be avoided or used cautiously.
- phenelzine
green tea, phenelzine. Other (see comment). Use Caution/Monitor. Comment: Avoid combination or excessive consumption of green tea. Combination may increase risk of cardiac arrhythmias or severe hypertension can occur due to caffeine component of green tea.
- phentermine
green tea, phentermine. Other (see comment). Use Caution/Monitor. Comment: Green tea may include caffeine. Caffeine is a CNS-stimulant and additive effects may be seen when coadministered with other CNS stimulants. Caffeine should be avoided or used cautiously.
- phenytoin
phenytoin decreases levels of green tea by increasing metabolism. Use Caution/Monitor. (Caffeine). Potential for decreased effects of caffeine in green tea. .
- pirbuterol
green tea increases effects of pirbuterol by pharmacodynamic synergism. Use Caution/Monitor. Due to caffeine content. Combination may increase CNS stimulatory effects due to caffeine in green tea.
- piroxicam
green tea, piroxicam. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- prasugrel
green tea increases effects of prasugrel by pharmacodynamic synergism. Use Caution/Monitor. (Theoretical interaction). Combination may increase risk of bleeding.
- procarbazine
green tea, procarbazine. Other (see comment). Use Caution/Monitor. Comment: Avoid combination or excessive consumption of green tea. Combination may increase risk of cardiac arrhythmias or severe hypertension can occur due to caffeine component of green tea.
- rasagiline
green tea, rasagiline. Other (see comment). Use Caution/Monitor. Comment: Avoid combination or excessive consumption of green tea. Combination may increase risk of cardiac arrhythmias or severe hypertension can occur due to caffeine component of green tea.
- reteplase
green tea, reteplase. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- salmeterol
green tea increases effects of salmeterol by pharmacodynamic synergism. Use Caution/Monitor. Due to caffeine content. Combination may increase CNS stimulatory effects due to caffeine in green tea.
- selegiline
green tea, selegiline. Other (see comment). Use Caution/Monitor. Comment: Avoid combination or excessive consumption of green tea. Combination may increase risk of cardiac arrhythmias or severe hypertension can occur due to caffeine component of green tea.
- selegiline transdermal
green tea, selegiline transdermal. Other (see comment). Use Caution/Monitor. Comment: Avoid combination or excessive consumption of green tea. Combination may increase risk of cardiac arrhythmias or severe hypertension can occur due to caffeine component of green tea.
- sertraline
green tea, sertraline. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- sulindac
green tea, sulindac. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- tenecteplase
green tea, tenecteplase. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- terbutaline
green tea increases effects of terbutaline by pharmacodynamic synergism. Use Caution/Monitor. Due to caffeine content. Combination may increase CNS stimulatory effects due to caffeine in green tea.
- theophylline
green tea increases levels of theophylline by decreasing renal clearance. Use Caution/Monitor. Due to caffeine content.
- ticlopidine
green tea increases effects of ticlopidine by pharmacodynamic synergism. Use Caution/Monitor. (Theoretical interaction). Combination may increase risk of bleeding.
- tirofiban
green tea increases effects of tirofiban by pharmacodynamic synergism. Use Caution/Monitor. (Theoretical interaction). Combination may increase risk of bleeding.
- tolmetin
green tea, tolmetin. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- tranylcypromine
green tea, tranylcypromine. Other (see comment). Use Caution/Monitor. Comment: Avoid combination or excessive consumption of green tea. Combination may increase risk of cardiac arrhythmias or severe hypertension can occur due to caffeine component of green tea.
- trazodone
green tea, trazodone. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- treprostinil
green tea, treprostinil. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- venlafaxine
green tea, venlafaxine. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.
- verapamil
verapamil increases levels of green tea by decreasing elimination. Use Caution/Monitor. (Caffeine). Verapamil reduces clearance of caffeine and increases serum caffeine concentrations, presumably via inhibition of hepatic metabolism. May advise patients to limit or minimize the intake of caffeinated products to minimize caffeine-related side effects.
- yohimbine
green tea, yohimbine. Other (see comment). Use Caution/Monitor. Comment: Avoid combination or excessive consumption of green tea. Combination may increase risk of cardiac arrhythmias or severe hypertension can occur due to caffeine component of green tea.
Minor (36)
- acetaminophen
green tea increases effects of acetaminophen by pharmacodynamic synergism. Minor/Significance Unknown. (Theoretical, due to caffeine content).
- acetaminophen IV
green tea increases effects of acetaminophen IV by pharmacodynamic synergism. Minor/Significance Unknown. (Theoretical, due to caffeine content).
- acetaminophen rectal
green tea increases effects of acetaminophen rectal by pharmacodynamic synergism. Minor/Significance Unknown. (Theoretical, due to caffeine content).
- alprazolam
green tea decreases effects of alprazolam by pharmacodynamic antagonism. Minor/Significance Unknown. Caffeine component of green tea may decrease sedative effects of benzodiazepines.
- American ginseng
green tea, American ginseng. Other (see comment). Minor/Significance Unknown. Comment: Use caution when combining green tea with herbs that exhibit antiplatelet effects or anticoagulant activity.
- carbamazepine
carbamazepine will decrease the level or effect of green tea by increasing metabolism. Minor/Significance Unknown.
- chlordiazepoxide
green tea decreases effects of chlordiazepoxide by pharmacodynamic antagonism. Minor/Significance Unknown. Caffeine component of green tea may decrease sedative effects of benzodiazepines.
- cimetidine
cimetidine will increase the level or effect of green tea by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown. Green tea may contain caffeine. CYP1A2 inhibitors may inhibit the hepatic oxidative metabolism of caffeine.
- ciprofloxacin
ciprofloxacin increases levels of green tea by decreasing elimination. Minor/Significance Unknown. (Caffeine). Some quinolones can inhibit the hepatic clearance of caffeine. Caution is advised.
- clonazepam
green tea decreases effects of clonazepam by pharmacodynamic antagonism. Minor/Significance Unknown. Caffeine component of green tea may decrease sedative effects of benzodiazepines.
- clorazepate
green tea decreases effects of clorazepate by pharmacodynamic antagonism. Minor/Significance Unknown. Caffeine component of green tea may decrease sedative effects of benzodiazepines.
- diazepam
green tea decreases effects of diazepam by pharmacodynamic antagonism. Minor/Significance Unknown. Caffeine component of green tea may decrease sedative effects of benzodiazepines.
- dihydroergotamine
green tea increases levels of dihydroergotamine by enhancing GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown. Due to caffeine content.
- dihydroergotamine intranasal
green tea increases levels of dihydroergotamine intranasal by enhancing GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown. Due to caffeine content.
- dong quai
green tea, dong quai. Other (see comment). Minor/Significance Unknown. Comment: Use caution when combining green tea with herbs that exhibit antiplatelet effects or anticoagulant activity.
- ergotamine
green tea increases levels of ergotamine by enhancing GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown. Due to caffeine content.
- feverfew
green tea, feverfew. Other (see comment). Minor/Significance Unknown. Comment: Use caution when combining green tea with herbs that exhibit antiplatelet effects or anticoagulant activity.
- formoterol
green tea increases effects of formoterol by pharmacodynamic synergism. Minor/Significance Unknown. Due to caffeine content. Combination may increase CNS stimulatory effects due to caffeine in green tea.
- garlic
green tea, garlic. Other (see comment). Minor/Significance Unknown. Comment: Use caution when combining green tea with herbs that exhibit antiplatelet effects or anticoagulant activity.
- ginger
green tea, ginger. Other (see comment). Minor/Significance Unknown. Comment: Use caution when combining green tea with herbs that exhibit antiplatelet effects or anticoagulant activity.
- ginkgo biloba
green tea, ginkgo biloba. Other (see comment). Minor/Significance Unknown. Comment: Use caution when combining green tea with herbs that exhibit antiplatelet effects or anticoagulant activity.
- grapefruit
grapefruit will increase the level or effect of green tea by Other (see comment). Minor/Significance Unknown. This food-drug interaction might potentiate the clinical effects and duration of action of caffeine.
- guarana
green tea, guarana. Other (see comment). Minor/Significance Unknown. Comment: Concurrent administration of guarana to patients taking caffeine may produce excessive caffeine-like side effects, such as nausea, irritability or nervousness. Caution in patients consuming large amounts of caffeine.
- levofloxacin
levofloxacin increases levels of green tea by decreasing elimination. Minor/Significance Unknown. (Caffeine). Some quinolones can inhibit the hepatic clearance of caffeine. Caution is advised.
- lithium
green tea increases levels of lithium by unspecified interaction mechanism. Minor/Significance Unknown. Lithium levels may increase following abrupt caffeine withdrawal.
- lorazepam
green tea decreases effects of lorazepam by pharmacodynamic antagonism. Minor/Significance Unknown. Caffeine component of green tea may decrease sedative effects of benzodiazepines.
- mestranol
mestranol increases levels of green tea by decreasing elimination. Minor/Significance Unknown. (Caffeine).
- midazolam
green tea decreases effects of midazolam by pharmacodynamic antagonism. Minor/Significance Unknown. Caffeine component of green tea may decrease sedative effects of benzodiazepines.
- oxazepam
green tea decreases effects of oxazepam by pharmacodynamic antagonism. Minor/Significance Unknown. Caffeine component of green tea may decrease sedative effects of benzodiazepines.
- panax ginseng
green tea, panax ginseng. Other (see comment). Minor/Significance Unknown. Comment: Use caution when combining green tea with herbs that exhibit antiplatelet effects or anticoagulant activity.
- phenobarbital
phenobarbital will decrease the level or effect of green tea by increasing metabolism. Minor/Significance Unknown. Green tea products may contain caffeine. The metabolism of xanthines, such as caffeine, can be increased by concurrent use with barbiturates.
- primidone
primidone will decrease the level or effect of green tea by increasing metabolism. Minor/Significance Unknown. Green tea products may contain caffeine. The metabolism of xanthines, such as caffeine, can be increased by concurrent use with barbiturates.
- St John's Wort
St John's Wort will decrease the level or effect of green tea by increasing metabolism. Minor/Significance Unknown.
- temazepam
green tea decreases effects of temazepam by pharmacodynamic antagonism. Minor/Significance Unknown. Caffeine component of green tea may decrease sedative effects of benzodiazepines.
- willow bark
green tea, willow bark. Other (see comment). Minor/Significance Unknown. Comment: Use caution when combining green tea with herbs that exhibit antiplatelet effects or anticoagulant activity.
- zolpidem
green tea decreases effects of zolpidem by pharmacodynamic antagonism. Minor/Significance Unknown. Caffeine component of green tea may decrease sedative effects of zolpidem.
Adverse Effects
Frequency Not Defined
Agitation
Anxiety
Arrhythmias
Constipation
Convulsions
Delirium
Dependence
Diarrhea
Diuresis
Dizziness
GI upset
Headache
Heartburn
Hepatotoxicity
Hyperglycemia
Hypertension
Increased cholesterol
Increased respiration
Insomnia
Irritability
Loss of appetite
Nausea/vomiting
Nervousness
Palpitations
Restlessness
Tachycardia
Tinnitus
Tremor
Withdrawal symptoms
Warnings
Contraindications
Hypersensitivity
Avoid prior to surgery: may cause bleeding
Cautions
Anxiety disorders, arrhythmias, cardiac disease, depression, diabetes mellitus, hypertension, kidney disease, ulcers (gastric/duodenal)
Pregnancy & Lactation
Pregnancy Category: avoid use
Lactation: avoid use
Pregnancy Categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available.Pharmacology
Metabolism: N/A
Excretion: N/A
Mechanism of Action
Contains polyphenols (flavonoids): antioxidant, reduce DNA oxidative damage, inhib. carcinogen formation (e.g., nitrosamines)
Caffeine: CNS stimulant