Interaction databaseSupplement × PrescriptionReviewed May 2026

Grapefruit Juice and Lovastatin, contraindicated.

Grapefruit juice inhibits intestinal CYP3A4 and can substantially increase lovastatin exposure, raising myopathy and rhabdomyolysis risk.

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

At a glance

Substances
Grapefruit Juice and Lovastatin
Pair type
Contraindicated
Evidence (highest tier)
Strong
Source citations
1 source
Stack Score effect
−25 to your Stack Score (per scored contraindication row).
Scope
Supplement × Prescription
Last verified
May 30, 2026

Contraindicated · Strong evidence

Contraindicated

What is happening. Grapefruit juice inhibits intestinal CYP3A4 and can substantially increase lovastatin exposure, raising myopathy and rhabdomyolysis risk.

Mechanism. Furanocoumarins in grapefruit inhibit intestinal CYP3A4, reducing first-pass metabolism of lovastatin.

Recommendation. Avoid grapefruit and grapefruit juice while taking lovastatin unless your prescriber specifically says otherwise.

Sources (1)
  1. Bailey DG et al. Grapefruit juice-drug interactions. Br J Clin Pharmacol. 1998. PMID 9723817

Stack Score

How this pair moves the number.

Effect on the composite score

If both Grapefruit Juice and Lovastatin are in the same stack, this pair applies −25 to your Stack Score (per scored contraindication row).

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

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