Nutritional Pharmacology

Nutritional pharmacology is the point at which food, supplements, herbal products, nutrition support, and medication therapy influence one another. A nutrient can change absorption, metabolism, or elimination of a drug. A medication can, in turn, create a deficiency or alter the patient’s response to nutrition. The history must therefore go beyond prescribed medications. Ask about fasting, recent weight loss, vomiting, alcohol use, bariatric surgery, enteral feeding, parenteral nutrition, fortified foods, vitamins, minerals, and herbal products. Timing matters: a patient may take the correct drug at the wrong relationship to food or a feeding tube schedule. In Canada, vitamins, minerals, and herbals sold as natural health products are regulated as drugs under the Natural Health Products Regulations. A product should have a product licence and an NPN or DIN-HM before sale. That identifier does not make the product harmless, appropriate for the patient, or free of clinically important interactions. The actual product, dose, route, frequency, and start or stop date belong in the medication reconciliation.