Is it safe to drink green tea while taking omeprazole, or can it reduce the medication’s effectiveness?

Most people can safely drink green tea while taking omeprazole, and typical amounts of brewed green tea are unlikely to reduce omeprazole’s effectiveness. Omeprazole’s official labeling does not list green tea as a known interaction, though it does advise caution with herbal supplements in general. ^{[1] [2]} However, very high-dose green tea extracts (concentrated catechins such as EGCG found in some weight‑loss or “fat burner” supplements) could, in theory, affect how some medicines are absorbed or metabolized, so it’s wise to avoid large, supplemental doses unless discussed with a clinician. ^[3]

What the medication label says

• Omeprazole can change stomach acidity and may alter absorption of certain drugs (for example, it can decrease absorption of ketoconazole and increase absorption of digoxin), so manufacturers advise telling your doctor about all medicines and herbal products you use. ^{[4] [5]}
• The consumer guidance explicitly highlights herbals like St. John’s wort and rifampin as known concerns; green tea is not listed among specific contraindicated herbals. This suggests no established, clinically significant interaction with ordinary green tea. ^{[1] [2]}

What research shows about green tea and drug interactions

• Green tea catechins (like EGCG) can bind some drugs or influence drug‑metabolizing enzymes and transporters in lab and animal studies. In humans, at common beverage doses, only limited interactions have been observed. ^[3]
• Omeprazole’s main interaction pathway is via CYP2C19 (a liver enzyme) inhibition and by raising gastric pH; green tea’s effects at typical beverage doses do not reliably counteract these mechanisms in clinical studies. ^{[6] [5]}

Practical guidance

• Brewed green tea in moderation (for example, 1–3 cups per day) is unlikely to change omeprazole’s acid‑reducing effect or its overall benefit for reflux or ulcers. ^{[3] [6]}
• If you use high‑dose green tea extract capsules or powders, consider spacing them from your omeprazole by a few hours and monitor for symptom changes (heartburn relief, regurgitation), because concentrated catechins may have stronger pharmacologic effects than tea beverages. Discuss supplement use with your clinician or pharmacist. ^[3]
• Take omeprazole as directed (usually 30–60 minutes before a meal) to ensure it works as intended; timing tends to matter more than common beverages for its effectiveness. ^[5]

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Key points to remember

• No specific, proven interaction between brewed green tea and omeprazole is listed in official labeling, and moderate intake is generally considered safe. ^{[1] [2]}
• High‑dose green tea extracts may pose a greater theoretical risk of affecting drug handling, so use caution and seek advice before combining with omeprazole. ^[3]

If you notice your heartburn control worsening after starting a green tea extract supplement, it would be reasonable to stop the supplement and check in with your clinician or pharmacist for personalized advice.