1. Guidelines to Lower Risk of Drug-
Nutrient Interactions: 2012
Mario Wilmath, MD

2. Presentation Points
• Description of At-Risk Populations
• Identification of Drugs Classes
• Understand the Basic Nutrient Pharmacokinetics
• Examples of Drug-Nutrient Interactions
• How to determine Possible Treatments
• Creating a Plan to Prevent Nutrient Depletion

3. At-Risk Population
• Growing children
• Pregnant women
• Older adults
• Persons with serious health problems
– Persons who are poorly nourished
– Persons who drink alcohol excessively
• Polypharmacy
– Persons taking two or more medications at the same time
– Persons using prescription and over-the-counter
medications together
– Persons taking medications for long periods of time
• Persons not following medication directions

4. Overview
• Approximately 400 drugs currently used in clinical
practice have been shown to deplete specific
nutrients
• Nutrients most likely to be depleted:
– Co-enzyme Q10
– Folic acid
– B2
– B6
– Mg
– Zn

5. Medications Affect Nutrition Intake
• Decreasing food intake
• Decreasing nutrient absorption
• Slowing down nutrient production
• Interfering with nutrient metabolism
• Increasing nutrient excretion

6. Decreased Oral Intake or Appetite
• Medications that alter taste (dysgeusia)
– Captopril
– Clarithromycin
• Decrease saliva production (xerostomia)
– Antihistamines
– Antidepressants
– Antipsychotics
– Clonidine
– diuretics
• Make mastication and swallowing dificult

7. Scenarios Likely to Produce Nutrient-
Drug Interactions
• Constipation
• Inadequate or excessive fluid intake
• Need for a tyramine-restriction
Goal: Work to minimize consequences

8. Decreased Absorption
Physiology:
• Decreasing time in intestine
• Altering stomach acidity
• Damaging intestinal lining
• Competing for absorption
• Binding nutrients
Physical Interactions
Ca+2, Mg+2, Fe+3, Al+3, or Zn+2 can lower PO absorption
• levothyroxine
• quinolone
Tube feedings (TF) decreases
• phenytoin
• levothyroxine

9. Decreased Absorption Examples
– Laxatives increase intestinal motility -> decrease
nutrient absorption
– Antacids lower stomach acidity -> interfere with
Fe+3, folate, vitamin B12 absorption
– Cancer medications and treatments cause
intestinal desquamation -> decrease nutrient
absorption
– Anticonvulsants -> decrease folate absorption
– Bile acid binding resins -> decrease bile acids
needed to absorb fat-soluble vitamins A, D, E, K

10. Decreased Nutrient Production
• Antibiotics kill vitamin K producing bacteria in
the intestines
-> decreases vitamin K availability
• Methotrexate is an analagous structure to folate
-> competes with dihydrofolate reductase to convert
folate to active form -> folate deficiency

11. Increased Nutrient Excretion
• Isoniazid: Analagous structure to vitamin B6
and induces excretion of vitamin B6
• Anticonvulants: Cause the liver to remove
vitamin D from the body -> decreased calcium
absorption.

12. Interference & Depletion
• High dose zinc interferes with copper and iron
absorption
• Large amounts of iron interfere with zinc
absorption
• Valium, ativan: Deplete melatonin
• Lasix, Bumex: Deplete ascorbic acid
• Beta blockers, statins: Deplete CoQ10

13. Appropriate Prescribing
1. Established efficacy
2. Compatible safety
3. Low risk of drug interactions
4. Low risk of nutrient interactions
5. Known adjustments for disease states or
organ function
6. Convenient
7. Affordable

14. Prevention of Nutrient Depletion
1. Ask the patient to report new or intensified
symptoms when taking certain medications
2. Keep a list of all medications and over-the-
counter supplements
3. Choosing a Nutrient Rich Diet
4. Mineral & Vitamin Supplementation
5. Increased Fiber Intake

15. SUMMARY
• Nutrient depletion can be caused by medications
• Professional obligation to improve health outcomes
• Identified at-risk groups include elderly, children,
pregnant, and some disease states
• Ask patients about new or worsened symptoms
• Be able to counsel patients and other health care
professionals on medications that may alter
absorption, metabolism, production, or excretion or
vitamins and minerals
• Advise patients on the importance of vitamins,
minerals, and fiber as part of a well-balanced diet

16. REFERENCES
1.American Dietetic Association. ADA Nutrition Guide
2012
2.OSU Extension Service. Nutrition in the Community
Guide. 2008
3. Reuben DB, Herr KA, Pacala JT, et al. Geriatrics at your
fingertips: 2009, 11th Editiion. New York: The American
Geriatrics Society; 2009
4.St. John Center for Wellness and Family Medicine. D
ugs that Deplete Vitamins and Minerals. Roseville,
Michigan. 2012