Grapefruit juice (GFJ to its friends), like all citrus, bursts with crucial nutrients like vitamins C and A, antioxidants and potassium. But if you’re on HIV meds, squeeze an orange, lemon, lime or tangerine instead of a grapefruit. GFJ jacks up bloodstream levels of some HIV meds—especially protease inhibitors—too quickly, increasing the potential for harmful side effects. An equal-opportunity booster, GFJ also increases levels of antihistamines and drugs for blood pressure, high cholesterol and anxiety.
Blame bioflavonoids—compounds that provide anti-inflammatory and antiviral punch and help your body process vitamin C. Those in the juice and rind of grapefruit (naringenin, quercetin and kaempferol) inhibit a liver and intestinal enzyme vital to drug metabolism—and the resulting med-boosting effect lingers for days. The culprits also hide in bioflavonoid and quercetin supplements. But the grapefruit-seed extract NutriBiotic (liquid drops or capsules, which I use to soothe sore throats and sinus infections) is safe. The bummer bioflavonoids are too tiny there to matter. Now, orange you glad you know this?