Grapefruit juice can affect statin therapy in what way, and what should a patient be advised?

• A. Grapefruit has no effect on statins
• B. Grapefruit can interact with certain statins by inhibiting metabolism via CYP3A4, increasing plasma levels
• C. Grapefruit reduces absorption of statins
• D. Grapefruit increases the metabolism of all statins, lowering levels

Answer: (B)

Grapefruit juice can inhibit the enzyme CYP3A4 in the gut, which is responsible for metabolizing many statins. When this metabolism is blocked, the statin isn’t broken down as quickly, leading to higher circulating levels in the blood. That increase in drug exposure raises the risk of adverse effects, especially muscle-related toxicity like myopathy or even rhabdomyolysis, and can stress the liver.

Because of this, the patient should be advised to avoid grapefruit juice while taking statins that are primarily metabolized by CYP3A4 (such as simvastatin, atorvastatin, and lovastatin) or at least limit it and discuss alternatives with the clinician. If a non-CYP3A4–metabolized statin (like pravastatin or rosuvastatin) is used, grapefruit interaction is less of a concern, but it’s still wise to confirm with a healthcare provider and monitor for symptoms.