influences of drug in dietary status

• Introduction


  • How does the drug interfere with food intake?
  • How does the drug interfere with the maintenance of nutritional status?

  
• Ways drug can interfere with food intake


  • Inability to take food
  • Inability to obtain and prepare food

  
• Ways drug can interfere with maintenance of nutritional status

  • GI tract
  • Metabolic/ endocrine system
  • Electrolytes
  • Selected nutrients

  
• Many interactions exist between drugs & nutrients
• Interactions between drugs & nutrients

  • Use the same site for absorption
  • Metabolised using the same organ
  • Secreted using the same organ
• Poor nutritional status may impair drugs metabolism
• People at higher risk for drug-nutrient interactions

  • Impaired renal, hepatic, GI function
  • Nutritional compromised due to chronic disease
  • Recent weight loss or dehydration
  • On multiple or prolonged drug therapy
  • Extremes of age, with changes in lean body mass, total body fluids, plasma protein level

  
• Drugs treatment can have detrimental effect on nutritional status
• Drugs which are most likely to have nutritional implications

  • Narrow therapeutic margin
  • Need to be taken on prolonged period
  • The timing of food intake
  • Dietary restriction or regulation
  • Have side effects with appetite and gastric function
  • Compete with nutrient directly

  
• Elderly


  • Elderly consume most of the prescribed and unprescribed medication dispensed due to chronic diseases; HYP, DM, CVD
  • More likely to receive drugs which may impact on nutritional status; cytotoxic, anti-Parkinson drugs
  • Increased susceptibility drug-induced AE: Diminished salivation cause bulky drugs to stick to the esophageal mucosa, leads to failing hearing, vision, memory
  • Impaired mobility, often leads poor compliance, incorrect dosing

  
• Many medications have specific recommendations regarding food intake in order to maximize the absorption
• Such recommendations can alter the usual patterns of food intake and may reduce overall food intake, when meals are omitted, as it often the case in elderly
• Examples of medication with specific dosing instruction

  • 30 minutes before meals, or an empty stomach: phenoxymethylpenicillin, itraconazole
  • Not to be taken with indigestion medication: ketoconazole
  • Not to be taken with iron, zinc, antacid preparation: ofloxacin, levofloxacin, doxycycline, penicillamine
  • Not to be taken with milk, iron, Zn, antacid preparation: ciprofloxacin, norfloxacin, tetracycline

  
• Function of a drug

  • A drug is taken to prevent or treat sickness and disease
  • A comprehensive understanding of the interaction is crucial to comprehend the physiological processes within the body upon medication administration
• General drug's effects


  • Therapeutics effects (intended effects)
  • Side effects (Not necessarily harmful)
  • Adverse effects (May be harmful, May effects vital organ with prolonged usage, Can be minimize by reduce the dosage and switch medication)
  • Toxic effects (medication used in excess, Can be life threatening, Should stop)
• Therapeutic vs. side effects


  • Primary effects, desired therapeutic effects
  • Secondary effects aka side effects, all other effects beside primary effects, either beneficial or harmful
• Side effects of a drug can influence Nutritional status of the individual and Specific nutrient in the body
• 1. drugs interference with food intake

  • Many different disease require medication
  • Certain medications affects patient's food intake and cause nutritional disorders
  • Some medication can cause inability to take, obtain or prepare foods

  
• Common side effects of drugs causing inability to take food

  • Taste disturbances
  • Stomatitis
  • Dry mouth
  • Loss appetite
  • Dysphagia (difficulty in swallowing)

  
• 1. Taste disturbances


  The implication for drugs effects on nutrient intake both in quantity and profile, can be overlooked, but must be counteracted

  
• Category of taste disturbances

  • Ageusia: complete of one of the taste sensation, is rarely associated with drug therapy
  • Hypogeusia: reduction in overall sense od taste is commonly associated with drug therapy
  • Dysgeusia: an altered perception of taste, often described as bitter or metallic taste, commonly associated with drug therapy
  • Parageusia: a bad taste in the mouth, in the absence of a source of taste and is rarely associated with drug therapy

  
• Drugs related with ageusia & hypogeusia

  • Amphetamines (CNS stimulants)
  • Aspirin (analgesic)
  • Benzodiazepine (tranquiliser)
  • Carbamazepine (epilepsy)
  • Cimetidine (gastric ulcer)

  
• Drugs related with dysgeusia (metallic taste)

  • Allopurinol (gout)
  • Captopril (HYP/ Heart failure)
  • Metformin (DM)
  • Metronidazole, 12% (infection)
  • Nifedipine, 6% (angina, HYP)
  • Pentamidine, 32-72%
  • Sartans
  • Sulphasalazine

  
• Drugs related with dysgeusia (bitter taste)

  • Aspirin (pain killer)
  • Carbamazepine (epilepsy)
  • Clarithromycin (antibiotic)
  • 5-fluouracil (GI & breast CA)
  • Isosorbide mononitrate (angina/heart failure)
  • Lamotrigine (epilepsy)
  • Acetazolamide
  • Levodopa
  • Metolazone
  • Risperidone
• Minimising taste disturbances


  • Discontinue drug
  • Investigation into other causes such as dry mouth or depression (corrective action taken)
  • A clear association with a particular drug discontinuation of the offending drug
  • For bitter/metallic taste: Consider mouth spray anesthetic, If discontinuation of drugs is impossible, masking techniques using mouth sprays & lozenges containing local anesthetic can be useful for dysgeusia

  
• Taste disturbances


  • taste disturbances
  • stomatitis
  • dry mouth
  • dysphagia

  
• Other common side effects

  • nausea
  • vomiting
• Drugs that can cause taste disturbances and other side effects

  • Chemotherapy agents
  • Analgesic (opiates, NSAIDS)
  • Antibiotic (erythromycin)
  • Cardiac agents (digoxin, quinidine)
  • Oral contraceptives (estrogen, progesterone)
  • Metformin (DM)
  • Parkinson (bromocriptine, L-DOPA)
  • Anticonvulsant (phenytoin, carbamazepine)
  • Theophylline (asthma, COPD)
  • Anesthetics drugs (ketamine)
  • HAART, highly-active anti-retroviral treatment

  
• Dysphagia


  Difficulty swallowing
• Causes of drug-induced dysphagia

  • Inducing mechanical obstruction
  • Affecting neuromuscular control of swallowing
• How drugs can impair swallowing

  • Inability to obtain & prepare food

  
• Side effects that can interfere with food obtainment and preparation

  • Somnolence (sleepiness, drowsiness) - CNS
  • Dizziness - CNS
  • Neuropathy (neuromuscular system)
  • Severe myalgia (neuromuscular system)

  
• Side effects affecting the GI tract

  • Nausea, vomiting
  • Diarrhoea
  • Reduced motility (constipation, indigestion)

  
• Side effects affecting the metabolic/endocrine system

  • Weight gain, increase appetite
  • Weight loss, anorexia

  
• Side effects affecting electrolytes

  • hypo-, hyperkalaemia
  • Hypo- / hypernatremia
  • Hypo- / hypermagnesemia
  • Hypo- / hypernatremia
• Side effects affecting nutrient loss

  • vit. B12
  • fat-soluble vits. (ADEK)
  • Pyridoxine
  • Biotin
  • Folic acid

  
• To minimize nausea and vomiting


  1. Take medication with food

  2. Eat crackers, light dry cereal

  3. Avoid hot, spicy, greasy foods

  4. Carbonated drinks

  5. Replace fluid loss if vomiting

  6. Anti-nausea /anti-emetic medications

  
• Nausea and vomiting usually occur in early treatment and may resolve despite continued treatment
• To minimize diarrhoea


  1. Increase dose gradually

  2. Take medication with food

  3. Avoid spicy food, caffeine, dairy products

  4. Anti-diarrhoeal medications

  
• Diarrhoea is usually dose-related and symptoms usually resolve upon discontinuation of the medications