Chapter 17 Implications of Drug-Nutrient Interaction and Pharmacology

TABLE 17.3 cont. Food Supplements and Drug Interactions Supplement

Drug

Minerals Calcium

Digitalis Hydrochlorothiazide

Laxatives (abuse) Phenytoin Verapamil

Copper Iron

Penicillamine Penicillamine

Non-narcotic analgesic (aspirin, indomethacin)

Magnesium Phosphorus Potassium

Calcium carbonate Ethanol Antacids

Furosemide,

hydrochlorothiazide, spironolactone

Ethanol Zinc Other Supplements

Protein or amino acids

Tryptophan Levodopa, methyldopa

Theophylline Fluoxetine MAOIs

Concurrent use may potentially inhibit drug absorption/action.

Concurrent use may potentially decrease plasma half-life of the drug. Concurrent use may intensify agitation, restlessness, and GI problems.

Concurrent use may result in confusion, a deterioration in mental status, headaches, agitation, and other adverse effects.

Tricyclic antidepressants Variable results are observed when used to augment antidepressant effects.

Source: Adapted with permission from Morley JE, Glick Z, Rubenstein L, eds. Geriatric Nutrition: A Comprehensive Review. 2nd ed. New York, NY: Raven Press Ltd; 1995.

Penicillamine Ethanol

Reduces absorption Reduces absorption Reduces absorption

Effect

Concurrent use with vitamin D may result in hypercalcemia and may enhance the toxic effects of the drug.

Concurrent use with vitamin D may result in hypercalcemia. Reduced absorption Concurrent use may decrease both drug and calcium.

Concurrent use with vitamin D may counter the antidysrhythmic effect of the drug.

May induce mineral depletion Concurrent use may decrease drug effectiveness.

May aggravate or contribute to iron deficiency anemia (405 g daily in long-term use causes 308 mL fecal blood loss).

Concurrent use may impair iron absorption. Reduces absorption Reduces absorption

Monitor for abnormal levels.

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