NutriStack
Royal Jelly and Warfarin, a caution.
Royal Jelly has case-report evidence of potentiating warfarin. An elderly patient with previously stable warfarin therapy developed hematuria with INR 6.88-7.29 after starting Royal Jelly one week earlier, with no other clear medication, diet, travel, illness, alcohol, tobacco, or adherence explanation. The mechanism is unknown, but the observed INR rise and bleeding make the combination clinically important.
One pair, every claim cited. The two substances, the type, the mechanism, the recommendation, and the primary literature.
Same shape as the other 1,729 pairs in the public database.
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What the row says.
Every entry follows the same shape: what is happening, the mechanism, the recommendation, and the primary literature.
At a glance
- Substances
- Royal Jelly and Warfarin
- Pair type
- Caution
- Evidence (highest tier)
- Emerging
- Source citations
- 2 sources
- Stack Score effect
- −5 to your Stack Score (per scored caution row).
- Scope
- Supplement × Prescription
- Last verified
- May 30, 2026
Caution · Emerging evidence
Caution
What is happening. Royal Jelly has case-report evidence of potentiating warfarin. An elderly patient with previously stable warfarin therapy developed hematuria with INR 6.88-7.29 after starting Royal Jelly one week earlier, with no other clear medication, diet, travel, illness, alcohol, tobacco, or adherence explanation. The mechanism is unknown, but the observed INR rise and bleeding make the combination clinically important.
Mechanism. The mechanism has not been established. The published case suggests Royal Jelly exposure may increase warfarin anticoagulant response, but the responsible constituent and whether the effect is pharmacokinetic or pharmacodynamic are unknown.
Recommendation. Avoid Royal Jelly while taking warfarin unless your anticoagulation clinician has reviewed the risk. If Royal Jelly has already been started, tell the anticoagulation clinic promptly and ask whether INR should be checked sooner. Seek urgent care for visible bleeding, black stools, blood in urine, severe headache, weakness, or dizziness.
Stack Score
How this pair moves the number.
Effect on the composite score
If both Royal Jelly and Warfarin 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 documented at /methodology/stack-score.
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