Food & Nutrient Drug Interactions PDF

DRUG-FOOD AND DRUG -NUTRIENT INTERACTIONS DRUG-FOOD INTERACTIONS MAOl-tyramine interactions MAOI + tyramine in food → ↑blood tyramine (due to ↓of tyramine metabolism by the MAOl) Tyramine → (indirect sympat...

DRUG-FOOD AND DRUG -NUTRIENT INTERACTIONS DRUG-FOOD INTERACTIONS MAOl-tyramine interactions MAOI + tyramine in food → ↑blood tyramine (due to ↓of tyramine metabolism by the MAOl) Tyramine → (indirect sympathomimetic) ↑ blood catecholamines by stimulating their release Uncontrolled catecholamine release ↓ Hypertensive crisis which is characterized by symptoms beginning with H: Hypertension Headache Heart problem (tachycardia, arrhythmia) Hemorrhage in brain ( stroke). Milk and dairy product-interactions Calcium in milk or dairy products + tetracycline or ciprofloxacin → Ca-antibiotic chelate → poor absorption of the antibiotic → ↓antimicrobial effectiveness. Drug-food rich in vitamin K interactions Warfarin (anticoagulant) + excessive amount of food rich in vitamin K (e.g. bran, liver, spinach, broccoli, cabbage, cauliflower and lettuce) → ↓warfarin effect → ↑possibility of thrombosis. Drug-grapefruit interactions Grapefruit juice → ↓CYP3A4 in small intestine and liver → ↓ intestinal and liver metabolism of drugs → ↑ blood levels, actions and side effects of drugs. Drug-fiber interactions Drug (e.g. atorvastatin) + fiber →↓GI absorption of the drug → ↓serum levels and effects of the drug. Drug-caffiene interactions Drug (e.g. cimetidine, ciprofloxacin, norfloxacin) + caffeine → ↓ metabolism of caffeine → ↑serum blood levels → excessive CNS or cardiovascular effects. 1  Drug-nutrient Interactions Drug-vitamin interactions B-carotene B-carotene + drug ( antibiotics, laxative, cholesterol lowering drugs) interfering with absorption of fat-soluble vitamins ADEK →↓ absorption and blood levels of B-carotene Folic acid Folic acid + antiepileptic drug (e.g. phenytoin) →↓folate ( by inhibiting folate absorption and induction of CYP450). Folic acid + antacids →↓folate absorption. Folic acid → folinic acid (active form) ↓of dihydrofolate reductase (by methotrexate) → ↓folinic acid → interference with physiological function of folic acid. Antibiotics (e.g. tetracycline) →↓intestinal flora (a major source of folic acid ) → folate depletion. Ascorbic acid Ascorbic acid (antioxidant) + aspirin → ↓mucosal damage and gastric acidity caused by aspirin-generated free radicals. Ascorbic acid → serum levels of estrogen in oral contraceptives → adverse reactions. Vitamin B complex + Oral contraceptives or tetracyclines → inhibiting absorption and blood levels of vitamins. + Isoniazid or cyclosporine → causing deficiency of vitamin B6 → anaemia and peripheral neuropathies. 2  Vitamin D + CYP450 inducer (phenobarbitone or phenytoin) → ↑vitamin D metabolism → ↓blood levels → symptoms of deficiency. + drug interfering with absorption (e.g. cholestyramine, neomycin, orlistat) → vitamin D deficiency. + drug enhancing bone mineralization (e.g. biphosphonate, estrogen/progestin) →synergestic interaction. Vitamin K + drug interfering with absorption (e.g. cholestyramine, mineral oil) → ↓absorption of vitamin K + Tetracyclines → ↓intestinal flora (major source of vitamin K) → vitamin K deficiency. Vitamin K (in excess) + warfarin → ↓warfarin effect → ↑risk of thrombosis. + CYP450 inducer (phenytoin) → ↑metabolism of vitamin K → vitamin K deficiency. 3  Drug-mineral Interactions Calcium + drug interfering with absorption of calcium (e.g. aluminium or magnesium-containing antacids, cholestyramine, tetracyclines, quinolones, corticosteroids) → ↓Ca absorption. + (phenytoin or phenobarbitone) → ↓ Ca absorption Iron +Chelating agent (e.g. clofibrate, deferoxamine, dimercaprol, EDTA, quinolones, tetracyclines) →↓iron absorption +Aspirin or NSAIDs ( chronic use) →↑ risk of gastrointestinal bleeding, iron deficiency and anaemia caused by NSAIDs. Iron (non-heme) + polyphenols and tannins (coffee, black or green tea, chamomile........) → binding iron → poorly absorbed complex. Limitation of coffee and other beverages containing tannins during pregnancy, lactation, infancy and childhood → ↓ risk of iron deficiency in infants and children. Potassium + (amphotericin B or colchicine or corticosteroids, laxatives) → hypokalemia. Hypokalemia → ↑risk of cardiotoxicity by digoxin. + (ACE inhibitors, losartan, spironolactone, cyclosporine) → hyperkalemia. Zinc + Ciprofloxacin or tetracyclines → chelation → ↓absorption and bioavailability of zinc and the antibiotic. 4