As with atorvastatin, simvastatin, and other statin drugs metabolized via CYP3A4, drinking grapefruit juice during lovastatin therapy may increase the risk of side effects. Components of grapefruit juice, the flavonoid naringin, or the furanocoumarin bergamottin inhibit CYP3A4 in vitro, and may account for the in vivo effect of grapefruit juice concentrate decreasing the metabolic clearance of lovastatin, and increasing its plasma concentrations.