MUSC Medical Center Pharmacy Services Title: Policy number: Origin date: Revised Date: Review date: Distribution: P&P References: Food - Drug Interaction D-01 6/97 08/00

Key words: food, drug, nutrient, interaction, patient education Policy: Interactions between medications and foods or nutrients can compromise therapy. Therefore, the Department of Pharmacy Services will be actively involved in detecting these interactions, incorporating information regarding these interactions on the pharmacy-generated medication administration record (MAR), and counseling patients on the potential for these interactions and how to avoid them. Procedures: 1. Identification of clinically significant food-drug interactions: a. The Drug Information Coordinator will notify a pharmacy member of the Nutrition Therapy Committee of any food-drug interactions for drugs newly added to the MUSC hospital formulary. b. The Nutrition Therapy Committee will review additions to and deletions from the MUSC formulary, as the need arises, in order to maintain an updated list of clinically significant food-drug interactions. c. As changes occur to the list of targeted food-drug interactions, a pharmacy member of the Nutrition Therapy Committee will be responsible for: i. updating the patient education brochure ii. notifying all pharmacists via E-mail and/or department staff meetings of changes to the current listing of targeted drugs iii. notifying all nurse manager via E-mail of changes to the current listing of targeted drugs iv. notifying the department=s information resources specialist of the need to update the MS Meds computer system. AFlagging@ medication-administration record (MAR) with guidelines on food-drug interactions: a. For all drugs targeted in the food-drug interaction program, the following statement will appear on the pharmacy-generated MAR: AFood-Drug Interaction. Educate patient and document teaching.@ b. The pharmacy department=s information resources specialist will enter the

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statement into the MS Meds computer system to print on the pharmacy-generated medication administration record (MAR). 3. Food-drug interaction patient education brochure: A patient education brochure listing the targeted food-drug interactions and guidelines for safe use will be distributed to all patients being discharged from the hospital on one or more of the targeted drugs. Patient education: a. Verbal and written patient instruction will be accomplished through interdisciplinary efforts of the nurse, pharmacist, dietitian, and/or physician. b. The appropriate pharmacist and/or dietitian will be available to provide assistance with patient education. c. The nurse administering the drug to the patient will note the food-drug interaction and will ensure that patient education is initiated. d. The nurse discharging the patient is responsible for ensuring that the patient and/or care giver has been counseled on the food-drug interaction, has been given the patient education brochure, and that this is documented in the patient medical record on the Interdisciplinary Patient / Family Education Flowsheet. Documentation of patient education: The person providing patient instruction (nurse, pharmacist, dietitian, or physician) must document in the patient record (on the education flowsheet as noted in 4d above) that the patient and/or caregiver was counseled on the fooddrug interaction and given the patient education brochure.

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Drug/Nutrient Class Anticoagulants

Medical University of South Carolina: Food-Drug Interactions Food-Drug Interaction Guidelines Specific Agents Alcohol can potentiate the effects of Alcohol should be avoided or an alternate Warfarin (Coumadin ®) warfarin in patients with concomitant anticoagulation regimen sought in patients liver disease. Vitamin E can with liver disease. Patients initiated on potentiate warfarin’s effects. High vitamin E may require dosing adjustments vitamin K content foods/enteral feeds downward to maintain a therapeutic INR. and large amounts of avocado can Patients should be instructed to eat consistent inhibit warfarin. quantities of vitamin K in their daily diets. Foods high in vitamin K include liver, broccoli, cauliflower, cabbage, kale, spinach and other green leafy vegetables, cheeses and certain vitamin supplements. Phenytoin (Dilantin ®) Serum phenytoin concentrations may be Hold enteral feeding 1 hour before and after decreased by continuous enteral feeds. dosing (check w/ MD for rate adjustment).

Anticonvulsant Agents

Anti-Neoplastic Agents

Procarbazine (Matulane ®)

Hypertensive urgency or emergency Patients should be instructed to avoid may result when combined with foods tyramine-containing foods (see MAOI section containing tyramine. above). Avoid alcohol and alcohol-containing products. May experience N/V with alcohol.

Antipsychotic Agents

Ziprasidone (Geodon ®)

Absorption increases as much as two times with food.

Take with food.

Drug/Nutrient Class Grapefruit juice

Specific Agents Multiple

Immunosuppressant Agents

Mycophenolate mofetil (CellCept ®)

Food-Drug Interaction Guidelines Grapefruit juice significantly increases Avoid grapefruit juice with these medications the bioavailability of the following unless instructed otherwise by your physician. drugs: Amlodipine (Norvasc ®) Buspirone (Buspar ®) Carbamazipine (Tegretol ®) Cisapride (Propulsid ®) Cyclosporin ( Gengraf ® Neoral ® Sandimmune ®) Diazepam (Valium ®) Dofetilide ( Tikosyn ®) Felodipine (Plendil ®) Lovastatin (Mevacor ®) Midazolam (Versed ®) Nifedipine (Procardia ®, Adalat ®) Nimodipine (Nimotop ®) Saquinivir (Fortovase ®) Simvastatin (Zocor ®) Sirolimus (Rapamune ®) Tacrolimus (Prograf ®) Triazolam (Halcion ®) Verapamil (Calan ®) Avoid grapefruit juice with this medication Grapefruit juice significantly decreases the bioavailability of the following drugs: Indinavir (Crixivan ®) Maximum serum concentrations of Take on empty stomach. active metabolite decreased by 40% with food.

Drug/Nutrient Class Monoamine Oxidase (MAO) Inhibitors

Specific Agents Phenelzine (Nardil ®) Selegiline (Eldepryl ®)

Food-Drug Interaction Guidelines Hypertensive urgency or emergency Patients should be instructed to avoid may result when combined with foods tyramine-containing foods. Tyraminecontaining tyramine (applies to all doses containing foods include aged cheese (except of phenelzine, but only doses >10mg/d cottage and cream cheese), non-fresh meats (salami, bologna, pepperoni), smoked, dried, for selegiline). or pickled fish (herring), liver, meat extracts, beer, ale, non-alcoholic beer, red wine, champagne, sherry, chianti, vermouth, broad (fava) beans, Brewer’s yeast, saurakraut, pickles, olives, red plums, overripe fruit. Efavirenz serum levels increase when taken after high fat meals. Avoid high fat meals.

Non-nucleoside Reverse Transcriptase Inhibitors (NNRTIs) Nucleoside Reverse transcriptase Inhibitors (NRTIs)

Efavirenz (Sustiva ®)

Didanosine (ddI; Videx ®) Didanosine serum levels decrease when Take didanosine ½ hour before or 2 hour after taken with food. meals. Abacavir (ABC; Ziagen ®) Abacavir serum levels increase when Avoid alcohol with abacavir. taken with alcohol.

Protease Inhibitors (PI’s)

Food decreases indinavir serum levels. Take indinavir 1 hour before or 2 hours after Indinavir (Crixivan ®) Food increases ritonavir serum levels. meals. May take with skim milk or a low fat Ritonavir (Norvir ®) meal if patient cannot tolerate taking on an Food and grapefruit juice increases Saquinavir (Fortovase ®) saquinavir serum levels. empty stomach. Nelfinavir (Viracept ®) Food increases nelfinavir serum levels. Take ritonavir with food if possible (may Lopinavir/ritonivir improve tolerability). Food increases lopinavir/ritonivir serum (Kaletra ®) Take saquinavir within 2 hours after a full levels. meal. Avoid grapefruit juice. Take nelfinavir with a meal or snack. Take lopinavir/ritonivir with food.

Drug/Nutrient Class Quinolone Antibiotics

Specific Agents Ciprofloxacin (Cipro ®) Gatifloxacin (Tequin ®)

Food-Drug Interaction Dairy products, enteral feeds and foods containing calcium, magnesium, aluminum, iron or zinc decrease absorption of oral fluoroquinolone antibiotics.

Guidelines Instruct patients to take ciprofloxacin 2 hours after a meal with an adequate amount of fluid. Gatifloxacin may be taken without regard to food. Avoid ingesting dairy products, or foods high in calcium, magnesium, aluminum, iron or zinc within 2 hours of taking ciprofloxacin or within 4 hours of taking gatifloxacin. Hold enteral feedings 2 hours pre- and post-dosing for ciprofloxacin (check with MD for rate adjustment). May also consider increasing the dose of the ciprofloxacin to overcome the drug-enteral interaction while maintaining the enteral regimen.

Tetracyclines

Dairy products and foods containing Instruct patients to take tetracycline 1 hour Tetracycline (Sumycin ®, calcium, magnesium, aluminum, iron or before or 2 hours after meals with adequate Achromycin ®) zinc decrease absorption of tetracycline. amounts of fluid. Avoid ingesting dairy Demeclocycline products, or foods high in calcium, magnesium, aluminum, iron or zinc within 2 hours of taking tetracycline. (Exception: may give with food if treating H. pylori.)

Steps in the Food-Drug Interactions Policy and Procedure: 1. Nurse notes the interaction “flagged” on the pharmacy-generated MAR with the following statement: “ **Food-Drug Interaction. Educate patient and document teaching.**” 2. Nurse initiates patient education or notifies pharmacist and/or dietitian to provide or assist with patient education. 3. Educate patient and/or caregiver with verbal and written materials. 4. Document patient education on the Interdisciplinary Patient / Family Education Flowsheet located in the patient medical record. 5. Nurse discharging the patient (a) checks the Interdisciplinary Patient / Family Education Flowsheet to ensure that the patient was educated, and (b) educates and /or reinforces patient education upon discharge and documents that was done.

Revised 8/01