Unit 11- Food-Drug Interactions Flashcards
Unit 11: Food-Drug Interactions
Importance of Awareness
• _____-________ interactions: specific changes to
pharmacokinetics of a drug caused by a nutrient, or
changes to the kinetics of a nutrient caused by a drug
• _____-______ interactions: broader term that also includes the effects of medication on nutritional status
—Very important to recognize for clinical, economic, and
legal reasons
– Ex. long-term effects of corticosteroids on _______ metabolism and the resulting osteoporosis
• Leads to LONGER or REPEATED hospital stays, use of MULTIPLE drugs, and deterioration of the patient!!!
Drug–nutrient
Food–drug
calcium
Unit 11: Food-Drug Interactions
Pharmacologic Aspects
• ________________: physiologic and biochemical EFFECTS of a drug or combination of drugs
(ex. mechanism of action)
• _________: MOVEMENT of a drug through the body by absorption, distribution, metabolism, and excretion (ex. time course)
____________: Genetically determined variations revealed only by effects of drugs
Pharmacodynamics
Pharmacokinetics
Pharmacogenomics
Unit 11: Food-Drug Interactions
Effects of Food on Drug Therapy
Drug absorption
1– Bioavailability-fraction of an administered drug that reaches the systemic circulation
2–– Effects of _____, _____, and other food components
3–– Chelation-sequestration of metal ions via multiple coordinate bonds
4–Adsorption-adhesion to a food component, slowing/reducing absorption
5-– GI pH-changes up or down can ______ the absorption of drugs
fiber, fat
decrease
Unit 11: Food-Drug Interactions
Medication and Enteral Nutrition Interactions
1—Physical __________
2—___________ of the drug
incompatibility
Bioavailability
Unit 11: Food-Drug Interactions
Other Effects of Food on Drug Therapy
1–Drug DISTRIBUTION
A– Albumin and binding sites
—Most important drug-binding protein in the blood
— LESS albumin= _____ binding sites=larger free fraction of drug in serum
2–Drug METABOLISM
A– Inhibition, __________
Ex. A diet high in Protein and low in Carbs can increase hepatic metabolism of theophylline (antiasthma drug)
• Ex. Furanocoumarins (found in grapefruits) can irreversibly inhibit (for up to 72 hours) the intestinal
metabolism of drugs such as calcium channel blockers and HMG-CoA reductase inhibitors, and lead to
possible toxicity
B–Competition for metabolizing enzymes
3–Drug EXCRETION
A– Renal resorption
B–Urine pH
EX..ALKALINE urine will allow basic drugs to be resorbed, and ACIDIC urine will allow acidic drugs to be resorbed from the urine back into the systemic circulation
EX. Milk, fruits, veggies are urine alkalinizers.
EX. _______ are acidifiers.
fewer
enhancement
Meats
100g of LICORICE— (the amount found in ~2 licorice
twists) can INCREASE cortisol concentration,
resulting in pseudohyperaldosteronism with
increased sodium resorption, water retention,
INCREASED blood pressure–WTF!?!—, and greater excretion of potassium
– The action of diuretics and antihypertensive drugs
may be antagonized!!
– The resultant hypokalemia may alter the action of
some drugs
EX FOR ME TO AVOID THIS AND OTHERS! DO MY RESEARCH!! G CHECK LICORICE AND SEE IF OTHERS POP UP!
Effects of Drugs on Food and Nutrition
Nutrient absorption X 6
1–– Chelation
• Cipro and tetracycline chelate Ca,Fe, Zn, Al, Mg
2—Adsorption-
• Questran (antidiarrhea) adsorbs Vitamins A, D, E, K
3–Transit time
• ________ decrease transit time and may lead to loss of Ca and K
Laxatives
Effects of Drugs on Food and Nutrition
Nutrient absorption X 6
4—GI environment
• Alteration of pH by Antacids, Histamine-receptor antagonists, and proton-pump inhibitors can impair Vitamin B12 absorption
5—Damage intestinal mucosa
• Overall malabsorption
• Fe and Ca absorption greatly affected
6—Intestinal transport
• Leads to _______ of folate transport and impaired absorption of Vitamin B12
inhibition
Effects of Drugs on Food and Nutrition
Nutrient metabolism
A—– Increase ________ of metabolism
• Anticonvulsants increase the metabolism of Vitamins B9
, D, and K
B—– Vitamin ________
• Anti-TB drug INH blocks conversion of Vitamin B6 to its active form
• Methotrexate (cancer and RA Tx) antagonizes folic acid
• Statins negatively affect the formation of CoQ10
Nutrient excretion
A– Interfere with nutrient resorption
B–Increase or decrease excretion
speed
antagonism
Alcohol
1–Additive toxicity
2– Excessive drowsiness with CNS depressants
3–Stomach mucosal irritant exacerbates NSAIDs or aspirin
4– Hepatotoxic
5–Inhibits gluconeogenesis (especially in the fasting state)
6–Combination with Aldehyde Dehydrogenase inhibitors can be fatal
7–Affects physical characteristics of medication
KNOW
Effects of Drugs on Nutritional Status
1–Side effects-undesirable effects
2– Oral, taste, and smell
– ______ (taste alteration) and ________ (aftertaste)
– Metallic or salty taste
– Antineoplastic drugs can cause painful mucositis
Dysgeusia
hypogeusia
Effects of Drugs on Nutritional Status
3---GI effects – Irritation and ulceration – Nausea and vomiting – Constipation or \_\_\_\_\_\_\_\_ – Destruction of intestinal bacteria – Fat malabsorption
diarrhea
Effects of Drugs on Nutritional Status
4—Appetite changes
– Undesired weight changes
– Nutritional imbalance
– Growth retardation in children
– Appetite suppressants
• Most CNS stimulants
– Stimulant drugs may cause _______
– CNS side effects
• Drowsiness, dizziness, ataxia, confusion, headache, weakness, tremor
– Appetite stimulants: undesirable and desirable
• ___________ drugs can lead to weight gains of 40-60 lbs in a few months
• Hormones, steroids, and marijuana derivatives
5–Organ system toxicity
6–Glucose levels
hypertension
Antipsychotic
Excipients and Food–Drug Interactions
Excipients: _____ _______ added as buffers, binders,
fillers, diluents, disintegrants, glidants, flavorings, dyes,
preservatives, suspending agents, or coatings
inactive ingredients
Focal Points
1–• Because of the importance of food–drug interactions in the effectiveness of medication and the overall health care provided, various strategies have been undertaken at health care facilities to meet The Joint Commission’s requirements for food–drug interaction counseling.
2–• _________- is considered to be a nutritional risk factor.
3—• The ______ should evaluate food–drug interactions as part of a comprehensive nutrition assessment.
4–• ________ in the medical record is required when instruction has been given, including assessment of the patient’s comprehension, ability, and willingness to follow instructions.
Polypharmacy
dietitian
Documentation
