What kind of interaction is it?

Caution: an interaction that may reduce efficacy or raise side-effect risk and warrants monitoring.

Is this interaction backed by published research?

Yes. NutriStack lists 2 citation rows for the Felodipine + Green Tea Extract pair, each linking to PubMed by PMID where available. Full sourcing methodology at https://nutristackapp.com/methodology/interactions.

Supplement × Prescription·a caution·Insufficient evidence

Felodipine + Green Tea Extract

Q: Can I take Felodipine and Green Tea Extract together?

Possibly, but with caution. Felodipine and Green Tea Extract have a documented caution-tier interaction. Green tea catechins can inhibit intestinal organic anion transporting polypeptides and may modestly affect CYP3A4 and P-glycoprotein, with the potential to alter felodipine absorption. Concentrated green tea extracts in supplement form deliver far higher catechin loads than brewed tea and carry an established risk of hepatotoxicity that can complicate the picture.

Q: How does this affect a NutriStack Stack Score?

-5 to your Stack Score per scored caution row.

Caution Insufficient evidence

Green tea catechins can inhibit intestinal organic anion transporting polypeptides and may modestly affect CYP3A4 and P-glycoprotein, with the potential to alter felodipine absorption. Concentrated green tea extracts in supplement form deliver far higher catechin loads than brewed tea and carry an established risk of hepatotoxicity that can complicate the picture.

Supplement × Prescription

Open the interaction checker → Read the methodology

From the database

What the row says.

Every entry follows the same shape: what is happening, the mechanism, and the recommendation.

Substances

Felodipine and Green Tea Extract

Pair type

Caution

Evidence

Insufficient

Source citations

Scope

Supplement × Prescription

Last verified

June 4, 2026

CautionInsufficient evidence

What is happening. Green tea catechins can inhibit intestinal organic anion transporting polypeptides and may modestly affect CYP3A4 and P-glycoprotein, with the potential to alter felodipine absorption. Concentrated green tea extracts in supplement form deliver far higher catechin loads than brewed tea and carry an established risk of hepatotoxicity that can complicate the picture.

Mechanism. Green tea polyphenols (notably EGCG) can inhibit drug transporters and modulate CYP3A4 in the gut, potentially changing the oral exposure of CYP3A4 substrates such as felodipine; the high-potency extract also poses an independent hepatotoxicity risk.

Recommendation. Be cautious with high-dose green tea extract supplements while on felodipine. Separate ingestion from the dose where possible, watch for changes in blood pressure or unexpected adverse effects, and report signs of liver injury such as dark urine, jaundice, or abdominal pain.

Stack Score

How it moves the number.

Effect on the composite score

If both Felodipine and Green Tea Extract are in the same stack, this pair applies −5 to your Stack Score (per scored caution row).

The full algorithm, the clamping rules, and four worked stacks are at /methodology/stack-score.

Sources

Sources, by evidence tier.

Every claim on this page is cited. PMIDs link straight to PubMed.

Reference material

1Misaka S, Yatabe J, Muller F, et al. Green tea ingestion greatly reduces plasma concentrations of nadolol in healthy subjects. Clin Pharmacol Ther. 2014.Needs sourceNo link
2Hu J, Webster D, Cao J, Shao A. The safety of green tea and green tea extract consumption in adults. Regul Toxicol Pharmacol. 2018.Needs sourceNo link

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