Beta-blockers, Propranolol, and Metoprolol. Caffeine, including caffeine from green tea, may increase blood pressure in people taking propranolol Inderal and metoprolol Lopressor, Toprol XL.

These medications are used to treat high blood pressure and heart disease. Blood-Thinning Medications. People who take warfarin Coudamin should not drink green tea. Since green tea contains vitamin K, it can make this medication ineffective. Other compounds in green tea may slow blood clotting and therefore increase the blood-thinning effect of these medications.

You should not mix green tea and aspirin because they both prevent blood from clotting. Using the two together may increase your risk of bleeding. If you are taking medications that promote blood thinning, discuss green tea consumption with your physician.

The combination of green tea and chemotherapy medications, specifically doxorubicin and tamoxifen, increased the effectiveness of these medications in laboratory tests.

However, the same results have not been found in studies on people. On the other hand, there have been reports of both green and black tea extracts affecting a gene in prostate cancer cells that may make them less sensitive to chemotherapy drugs. For that reason, people should talk to their doctors before drinking black and green tea or taking tea extracts while undergoing chemotherapy.

Clozapine Clozaril. The effects of the clozapine may be reduced if taken within 40 minutes after drinking green tea. When taken with ephedrine, green tea may cause agitation, tremors, insomnia, and weight loss. Green tea has been shown to reduce blood levels of lithium, a medication used to treat bipolar disorder.

That can make lithium less effective. Monoamine Oxidase Inhibitors MAOIs. Green tea may cause a severe increase in blood pressure, called a "hypertensive crisis," when taken together with these drugs used to treat depression.

Examples of MAOIs include:. Birth control pills. Oral contraceptives can prolong the amount of time caffeine stays in the body, which may increase its stimulating effects. A combination of caffeine, including caffeine from green tea, and phenylpropanolamine, used in many over-the-counter and prescription cough and cold medications and weight loss products, may cause mania and a severe increase in blood pressure.

The FDA issued a public health advisory in November to warn people of the risk of bleeding in the brain from use of this medication and urged all manufacturers of this drug to remove it from the market.

Most drugs that contained phenylpropanolamine have been reformulated without it. Quinolone antibiotics. Green tea may make these medications more effective and also increase the risk of side effects.

These medications include:. Other medications. Green tea, especially caffeinated green tea, may interact with a number for medications, including:. To be safe, check with your health care provider before drinking or taking green tea if you also take other medications.

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J Nutr. Nagao T, Hase T, Tokimitsu I. Learn about seven teas and herbal infusions that might provide relief. Sipping a hot cup of tea makes us feel better when we're sick, but certain teas may actually ease the symptoms of your cold.

We look at the research…. Fennel tea tastes a little like licorice, with a relaxing scent and slightly bitter aftertaste. Learn about its benefits for your health. Over-the-counter antacids may help reduce indigestion symptoms, but what are some home remedies for indigestion?

We'll tell you what you can try…. A Quiz for Teens Are You a Workaholic? How Well Do You Sleep? Health Conditions Discover Plan Connect.

Nutrition Evidence Based 9 Teas to Soothe an Upset Stomach. Medically reviewed by Amy Richter, RD , Nutrition — By Rachael Ajmera, MS, RD — Updated on April 17, Green tea. Ginger tea. Peppermint tea. Black tea.

Fennel tea. Licorice tea. Chamomile tea. Holy basil tea. Spearmint tea. The bottom line. How we reviewed this article: Sources. Healthline has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations.

We avoid using tertiary references. You can learn more about how we ensure our content is accurate and current by reading our editorial policy. Apr 17, Written By Rachael Ajmera, MS, RD. Feb 22, Medically Reviewed By Amy Richter, MS, RD. Share this article. Read this next. By Marsha McCulloch, MS, RD and Rachael Ajmera, MS, RD.

Medically reviewed by Debra Rose Wilson, Ph. By Lizzie Streit, MS, RDN, LD. What Are the Best Teas for Soothing a Sore Throat?

Medically reviewed by Elaine K. Luo, M. What Is Fennel Tea? How to Treat Indigestion at Home. Green tea extract prevents obesity in male mice by alleviating gut dysbiosis in association with improved intestinal barrier function that limits endotoxin translocation and adipose inflammation.

The Journal of Nutritional Biochemistry, 67, Yan, Z. Antioxidant mechanism of tea polyphenols and its impact on health benefits. Animal Nutrition,6 2. Ogita, T. Oral Administration of Flavonifractor plautii Strongly Suppresses Th2 Immune Responses in Mice. Frontiers in Immunology, Exclusively written for thefunctionagutclinic.