Diet, Medications, and Dietary Supplements Chapter 19 MEDICATIONS IN DISEASE TREATMENT Prescription Medications Usually given to treat serious conditions May cause side effects Physician evaluates the benefits of using the prescription medication vs. the risks of incurring side effects Over-the-Counter Drugs Usually can be used safely and effectively without medical supervision Used to treat less serious illnesses that are easily self-diagnosed and do not ordinarily cause serious side effects Labels are regulated and provide information about Appropriate uses Dosages Potential adverse effects Over-the-Counter Drugs Caution patients about adverse effects if used inappropriately Caution patients about potential toxicity of active ingredients Patient taking acetaminophen for headache and taking a cold preparation Generic Drugs Sold after patent protection of brandname drugs expire Safe and effective as the brand-name products they replace Chemically identical in structure to brand-name drugs Offer substantial savings, usually 20 to 75% less than brand-name drugs 1
Side effects Majority revealed during clinical trials Food and Drug Administration (FDA) monitors adverse events after drugs are marketed Manufacturers require periodic reports Diet-drug interactions Substances in diet may alter effectiveness of drugs Drugs may affect food intake or nutrient metabolism Medication errors Account for approximately 7000 deaths yearly According to FDA - From 1993 1998 most common error leading to patient death administration of improper dosages or incorrect drugs Look- or sound-alike drugs Similar packing Medication errors (cont d) 2004, JCAHO New set of prohibited abbreviations, acronyms, and symbols for accredited health care organizations 2004, FDA required bar code identifications on medications used in health care institutions Medication errors (cont d) Hospital patients will wear bar-coded identification bracelets that link computerized medical records with drugdispensing information Error messages occur if drug, dosage or timing of administration is not appropriate for the patient 2
Patients at high risk of adverse effects Pregnant and nursing women Children Older adults Reducing risks Don t take medications unless absolutely necessary Dietary alternatives Lifestyle alternatives Reducing risks Obtain a complete list of prescription meds, OTC drugs and dietary supplements that a patient is taking. One physician coordinating medications usage. Purchase all medications at the same pharmacy. Reducing risks Encourage patients to keep track of side effects and keep physician informed. Alert patient to potential interactions between drugs and/or drugs and dietary supplements. DIETARY SUPPLEMENTS Herbal and Specialty Supplements 1/3 of older adults use herbal or specialty supplements. Top selling herbal supplements include: Ginseng Echinacea Ginkgo biloba Garlic St. John s wort 3
Efficacy Limited clinical studies support the traditional uses of herbal supplements. National Center for Complementary and Alternative Medicine funding large, controlled trials of several popular herbal treatments. Consistency of herbal ingredients May vary in composition. Dosage on the label may not provide the amount of active ingredients found to be effective. Safety Issues Most common side effects diarrhea, nausea, and vomiting Kava, chaparral, and comfrey have caused liver damage Yohimbe (promoted for bodybuilding) linked to renal failure, seizures, and heart palpitations Ephedra (ma huang removed from the market causes heart attack or stroke) Safety Issues Adverse effects of herbs - rarely listed on label Herbs may increase or decrease the effects of medications raise risk of toxicity Garlic, ginkgo, and ginseng increase risk of bleeding with anticoagulants 4
Safety Issues St. John s wort inhibits actions of oral contraceptives, anticoagulants and other drugs Ginger and ginseng raise blood pressure and may increase the toxicity of drugs that have a similar side effect Safety Issues (cont d) Possible contamination of herbal products Of 251 products imported from Asia 10% contained lead 14% contained arsenic 14% contained mercury Reports of intentional or accidental substitutions of one plant species for another Use of for Illness Consequences can sometimes be serious and irreversible. Consumers should inform their health care providers about use of dietary supplements. Research on herbs is limited. DIET-DRUG INTERACTIONS Several resources for health practitioners are listed at the end of this chapter. Medications and Food Intake Drug complications that alter food intake Antineoplastic cancer chemotherapy. Antiretroviral agents drugs used to treat HIV infection. Nausea and vomiting may impede recovery. 5
Medications and Food Intake Medications that alter appetite Some medications are prescribed to stimulate food intake and weight gain (AIDS and cancer patients). Some medications have side effects that produce unintentional weight gain (antipsychotics, antidepressants, and corticosteroids). Some medications prescribed for obesity to suppress appetite and promote weight loss (sibutramine, amphetamines, amphetamine-like compounds). Absorption Medication effects on nutrient absorption Drug-nutrient binding Bile acid binders to reduce cholesterol levels and also bind to fat-soluble vitamins. Some antibiotics bind to calcium, and other minerals in foods and supplements. Consume dairy products and mineral supplements at least 2 hours apart from these medications. Altered acidity in the stomach Absorption Medication effects on nutrient absorption Altered acidity in the stomach may impair absorption of B 12, folate, and iron. Antacids Proton pump inhibitors H2 blockers Direct inhibition 6
Absorption Medication effects on nutrient absorption Direct inhibition Several drugs directly impede the absorption of nutrients by interfering with intestinal metabolism or transport into mucosal cells. Absorption Dietary effects on medication absorption Stomach emptying rate Stomach acidity Interactions with Food Components High fiber foods - phytates Metabolism Medication effects on nutrient metabolism Methotrexate and folate deficiency Phenobarbital and Phenytoin folate, vitamin D and K. Metabolism Medication effects on nutrient metabolism Grapefruit juice may increase half-life of numerous drugs. Vitamin K weakens effects of warfarin (other herbs). Excretion Medication effects on nutrient excretion Diuretics increase excretion of calcium, potassium, and magnesium. Isoniazid (antituberculosis drug) induces excretion of vitamin B 6. 7
Excretion Dietary effects on medication excretion Dehydration or sodium depletion lithium retention. Foods or drugs that increase alkalinity of urine may raise quinidine levels. Toxicity Combination of tyramine and monoamine oxidase (MAO) inhibitors (medications used to treat depression) can be fatal severe headaches, rapid heart beats, and dangerous increase in BP. Complementary and Alternative Medicine () Estimated $25 billion spent by Americans on in 1997 National Center for Complementary and Alternative Medicine established in 1998 Defining complementary and alternative medicine Variety of approaches, philosophies, and treatments Alternative = used in place of conventional medicine Complementary = used together with conventional medicine Integrative medicine referring patients for complementary therapies while practicing conventional medicine 8
Overview of therapies Alternative medical systems Naturopathic medicine Proposes that a person s natural life force can foster self-healing Special diets, fasting, herbal remedies/other supplements, acupuncture, homeopathy, massage, etc. Homeopathic medicine Based on the theory that like cures like Remedies usually diluted believe dilution increases potency Alternative medical systems Traditional Chinese medicine (TCM) Folk practices based on theory that the body has pathways (meridians) that conduct energy (qi) Illness = interrupted flow of qi Acupunture, qi gong, herbal remedies, dietary practices, massage Mind-body interventions Biofeedback Meditation Imagery Faith healing Biologically based therapies Hormones Glucosamine-chondroitin supplements Aromatherapy Manipulative and body-based methods Chiropractic alleges that keeping the nervous system free from obstruction allows the body to heal itself Massage therapy Energy therapies biofield therapies or bioelectrical / bioelectromagnetic therapies Acupuncture Qi gong Therapeutic touch 9
Is safe and effective? Does work? Well-controlled research studies are needed Potential hazards of Lack of regulation of supplements Delaying reliable conventional treatments while receiving therpies Working with patients who use Inquire about use of and educate patient about potential risks 10