What is green tea?
The use of green tea in cultural and traditional settings may differ from concepts accepted by current Western medicine. When considering the use of herbal supplements, consultation with a primary health care professional is advisable. Additionally, consultation with a practitioner trained in the uses of herbal/health supplements may be beneficial, and coordination of treatment among all health care providers involved may be advantageous.
Green tea is also known as Camellia sinensis.
Green tea has been used for stomach disorders, vomiting, diarrhea, to prevent dental cavities, to lower cholesterol levels, as an antioxidant, to reduce cancer, and as a stimulant.
Green tea has not been evaluated by the FDA for safety, effectiveness, or purity. All potential risks and/or advantages of green tea may not be known. Additionally, there are no regulated manufacturing standards in place for these compounds. There have been instances where herbal/health supplements have been sold which were contaminated with toxic metals or other drugs. Herbal/health supplements should be purchased from a reliable source to minimize the risk of contamination.
Green tea may also have uses other than those listed in this medication guide.
Do not use green tea without first talking to your doctor if you have
- heart problems or high blood pressure,
- kidney disease,
- an overactive thyroid (hyperthyroidism),
- an anxiety or nervous disorder, or
- a bleeding or blood clotting disorder or if you take a blood thinner such as warfarin (Coumadin).
Green tea contains a large amount of caffeine and may be problematic if used by people with any of the conditions listed above. You may not be able to use green tea, or your doctor or health care provider may recommend a lower dose or special monitoring.
Before taking green tea, talk to your doctor, pharmacist, or health care professional if you have allergies (especially to plants), have any medical condition, or if you take other medicines or other herbal/health supplements. Green tea may not be recommended in some situations.
Do not take green tea without first talking to your doctor if you are pregnant or could become pregnant. Green tea contains a large amount of caffeine.
Do not take green tea without first talking to your doctor if you are breast-feeding a baby. Green tea contains a large amount of caffeine, which may cause restlessness, sleep disorders, and other effects in breast-feeding infants.
There is no information available regarding the use of green tea by children. Green tea contains a large amount of caffeine, which may cause anemia and other problems in children. Do not give any herbal/health supplement to a child without first talking to the child’s doctor.
The amount of caffeine consumed in other products should be monitored while taking green tea.
There are no restrictions on food, beverages, or activity while taking green tea, unless otherwise directed by your health care provider.
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Seek emergency medical attention.
Symptoms of a green tea overdose are not well known but might include restlessness, tremor, vomiting, and abdominal spasms.
No information is available regarding a missed dose of green tea. Consult your doctor, pharmacist, or health care professional if you require further information.
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Although rare, allergic reactions to green tea may occur. Stop taking green tea and seek emergency medical attention if you experience symptoms of a serious allergic reaction including difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives.
Heavy and prolonged consumption of green tea may be associated with esophageal cancer.
Other less serious side effects have also been reported with the use of green tea. Talk to your doctor or health care provider if you experience
- upset stomach;
- loss of appetite;
- constipation or diarrhea;
- nervousness, irritability, or anxiety;
- irregular heartbeats; or
Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.
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Do not use green tea without first talking to your doctor if you are taking a blood thinner such as warfarin (Coumadin).
Interactions between green tea and other prescription or over-the-counter medicines or herbal/health supplements may also occur. Talk to your doctor, pharmacist, or health care professional before taking green tea if you are taking any other medicines or supplements.
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Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.
Copyright 1996-2004 Cerner Multum, Inc. Version 2.05. Revision date 8/23/04