Manual of Clinical Nutrition

Food and Drug Interactions

Manual of Clinical Nutrition Management II- 31 Copyright © 2013 Compass Group, Inc.

Medication

Classification

Effect of Food

on Medication

Effect of Medication on

Nutritional Status

Patient Guidelines

Thyroid
Preparation
Synthroid
Goitrogenic substances naturally
present in some foods can interfere
with iodine uptake by the thyroid

Take iron supplement separately by

4 hours

Take on empty stomach

If hypothyroidism is induced by

goitrogenic foods, one should

encourage thorough cooking to

inactivate the goitrogens in some

vegetables

Haloperidol

(Haldol)

May cause

additive

hypotension with

alcohol

Coffee or tea may

precipitate liquid

form of

medication

Appetite ; weight loss; anorexia

Dry mouth

Constipation

Take Fe supplement separately by 4

hours

Avoid consumption of coffee, tea, or

fruit juice 1 hour before or 2 hours

after taking liquid form

Take with food or milk

Miscellaneous
Cimetidine
(Tagamet)

Food delays

medication

absorption and

allows

maintenance of

an effective

blood

concentration

between doses

Aplastic anemia;  absorption of

vitamin B 12

Take with or directly after meals

Advise concerning taste changes

Protease Inhibitor

(Fortorase)

Grapefruit juice

may increase

medication

availability and

absorption (4,5).

Avoid grapefruit juice (4,5).

Benzodiazepines

Midazolam, and

Triazolam

(Halcion,

Clomipramine,

Anafranil)

Grapefruit juice

may increase

medication

availability and

absorption (4,5,8).

Avoid grapefruit juice (4,5,8).