Can I Take These?

Can You Take Caffeine and Warfarin Together?

Caffeine is listed as a CYP1A2 inhibitor on warfarin's FDA label, a class that can increase warfarin's effect.

Use cautionEvidence: Moderate

What the interaction means

Warfarin's FDA prescribing information's Table 2 ("Examples of CYP450 Interactions with Warfarin") lists caffeine under CYP1A2 Inhibitors. The label states: "Inhibitors of CYP2C9, 1A2, and/or 3A4 have the potential to increase the effect (increase INR) of warfarin by increasing the exposure of warfarin... Closely monitor INR if a concomitant drug is a CYP2C9, 1A2, and/or 3A4 inhibitor or inducer."

Why it may happen

CYP1A2 enzyme inhibition, per the label's general explanation for this table -- not further specified for caffeine individually.

Practical context

This is a generic-class table listing many drugs as CYP450 inhibitors/inducers, not a caffeine-specific subsection, and the label itself says the list "should not be considered all-inclusive." No spacing interval or dose threshold for caffeine specifically is given -- the label's guidance is to monitor INR, not to avoid caffeine.

What the sources say

Warfarin Sodium Tablets — FDA Prescribing Information — Amneal Pharmaceuticals LLC (via DailyMed, U.S. National Library of Medicine)

Last reviewed 2026-08-23

Medical information disclaimer: this information is general and educational. It does not diagnose conditions, prescribe treatment, or determine whether a combination is safe for you personally. Follow your prescription label and ask a pharmacist or clinician before starting, stopping, or combining products. Full disclaimer.

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