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© 2011 McGraw-Hill Higher Education. All rights reserved.
Chapter 12Chapter 12
Dietary Supplements and Over-the-Counter
Drugs
© 2011 McGraw-Hill Higher Education. All rights reserved.
Dietary Supplements vs. Dietary Supplements vs. DrugsDrugs
Drugs and food share certain characteristics They contain chemicals that interact
with the body’s physiology
Drugs and food are not regulated in the same ways
Supplements may be thought of as drugs by consumers but are legally classified as food products
© 2011 McGraw-Hill Higher Education. All rights reserved.
Dietary Supplements vs. Dietary Supplements vs. DrugsDrugs
Pills, capsules, liquids, and powders classified as dietary supplements may be thought of as drugs by consumers BUT They are legally classified as food products They are treated very differently by the Food and
Drug Administration (FDA)
Example of Saint John’s wort Many people take it for its suggested ability to
improve mood, reduce anxiety, and induce sleep Classified as a dietary supplement, it is regulated
more like a food than a drug
© 2011 McGraw-Hill Higher Education. All rights reserved.
Food, Drug, and Cosmetic ActFood, Drug, and Cosmetic Act
A drug is a product intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease
Before marketing, drugs must be shown to be Safe when used as directed Effective for their intended use
Food products and ingredients must be Safe Pure (unadulterated) They are not required to show that they are
effective or provide any benefit
© 2011 McGraw-Hill Higher Education. All rights reserved.
Dietary Supplements: Dietary Supplements: RegulationRegulation
Dietary Supplement Health and Education Act (DSHEA) of 1994 Passed in part due to pressure on
Congress from the supplement industry in response to indications that the FDA was planning to expand regulation of dietary supplements
Defined supplements and set regulations for safety and labeling
© 2011 McGraw-Hill Higher Education. All rights reserved.
DSHEA: Supplement LabelingDSHEA: Supplement Labeling
Same label format as those for packaged foods Not as accurate or precise as drug labels
Testing has found that potency varies from bottle to bottle and even capsule to capsule Amounts listed on label are for a plant substance and not
the presumed active ingredient
Ingredients listed on the label may not be the actual active ingredients in a plant or herb
Dosage guidelines are not well-established for many supplements
There is no requirement for proof of effectiveness
© 2011 McGraw-Hill Higher Education. All rights reserved.
DSHEA: Defining Dietary DSHEA: Defining Dietary SupplementsSupplements
DSHEA expanded the definition of supplements to include a variety of substances: Vitamins and minerals Herbs and concentrates and extracts of herbs Amino acids
Many forms: Tablets Capsules Liquids Powders
© 2011 McGraw-Hill Higher Education. All rights reserved.
DSHEA: Defining Supplement DSHEA: Defining Supplement SafetySafety
FDA can declare a product to be adulterated (unsafe) only if it presents a significant or unreasonable risk of illness or injury
Ingredients already on the market at the time of the Act: Considered safe enough to be sold unless the FDA
can demonstrate a risk
New ingredients: Need some evidence that they would not present a
significant or unreasonable risk BUT much less evidence is required than for drugs
© 2011 McGraw-Hill Higher Education. All rights reserved.
Supplement Labeling: Supplement Labeling: Health ClaimsHealth Claims
FDA authorizes a small number of health claims that food and supplement manufacturers can use if their products meet certain requirements Based on available scientific research Examples:
Adequate calcium intake and reduced risk of osteoporosis
Soluble fiber intake and reduced risk of heart disease
© 2011 McGraw-Hill Higher Education. All rights reserved.
Supplement Labeling: Supplement Labeling: Structure/Function ClaimsStructure/Function Claims
Unapproved health claims are not allowed, BUT
Supplement labels can make so-called structure/function claims Relate to the structure or functioning of the
body or to overall well-being Examples:
Maintains cell integritySupports the immune system
© 2011 McGraw-Hill Higher Education. All rights reserved.
Supplement Labeling: Supplement Labeling: Structure/Function ClaimsStructure/Function Claims
Not a claim to prevent or treat a disease Not reviewed by the FDA Must carry a disclaimer:
This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
Supplement LabelingSupplement Labeling
© 2011 McGraw-Hill Higher Education. All rights reserved.
© 2011 McGraw-Hill Higher Education. All rights reserved.
Pros and Cons of Current Pros and Cons of Current Supplement RegulationsSupplement Regulations
Pro: Many more supplements on the market Consumers have more options
Con: Much less research available about safety and effectiveness of supplements
Con: Supplements remain on the market unless or until the FDA presents clear evidence of risk Example: Ephedra, a stimulant taken by people
wanting to lose weight First evidence of safety concerns published by the FDA in
1994 With the burden of proof now with the FDA, it took 10
additional years for the FDA to compile evidence to get ephedra off the market
© 2011 McGraw-Hill Higher Education. All rights reserved.
Supplements to AvoidSupplements to Avoid
Definitely hazardous Aristolochic acid
Very likely hazardous Comfrey Androstenedione Chaparral Germander Kava Cesium Colloidial Siver Graviola
Likely hazardous Bitter orange Organ/glandular extracts Lobelia Pennyroyal oil Scullcap Yohimbe
© 2011 McGraw-Hill Higher Education. All rights reserved.
Dietary Supplement ActDietary Supplement Act
Introduced by Senator John McCain in February 2010.
Would have required all manufacturers to register with the FDA and provide a complete list of ingredients.
The FDA could also recall any ingredient they found to be unsafe.
The dietary supplement industry mounted a campaign against the regulation and McCain withdrew the bill
© 2011 McGraw-Hill Higher Education. All rights reserved.
Examples of Psychoactive Examples of Psychoactive Dietary SupplementsDietary Supplements
Saint John’s wort (Hypericum perforatum) Was originally thought to prevent possession by
demons Currently used as a potential treatment for both
anxiety and depression
Research results have been mixed, but there is some evidence supporting its use for depression
It may interact with prescription drugs, so users should notify their physicians
© 2011 McGraw-Hill Higher Education. All rights reserved.
Examples of Psychoactive Examples of Psychoactive Dietary SupplementsDietary Supplements
S-adenosyl-L-methionine (SAMe) A naturally occurring substance, the active
form of amino acid methionine Researched as a possible antidepressant Not yet any solid evidence it is more
effective than placebo
© 2011 McGraw-Hill Higher Education. All rights reserved.
Examples of Psychoactive Examples of Psychoactive Dietary SupplementsDietary Supplements
Ginkgo biloba Long history of medical use in China Active ingredients and mechanisms of action
haven’t yet been identified Reduces blood clotting; thins blood to improve
circulation Potentially risky if used with aspirin or other drugs
that reduce clotting
Research suggests a slight ability to improve memory
© 2011 McGraw-Hill Higher Education. All rights reserved.
Dietary Supplements vs. Dietary Supplements vs. Drugs: ReviewDrugs: Review
Supplements: no requirement for proof of effectiveness
Disclaimer for any structure/function claim: “This statement has not been evaluated by
the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.”
© 2011 McGraw-Hill Higher Education. All rights reserved.
Over-the-Counter (OTC) Over-the-Counter (OTC) DrugsDrugs
A drug is a product intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease
Usage by Americans Americans self-treat four
times as many health problems as doctors treat, often with OTC drugs
Americans spend over$18 billion per yearon OTC drugs
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC RegulationOTC Regulation
1962 Kefauver-Harris amendment required that all drugs be evaluated for safety and efficacy
Active ingredients reviewed individually; three standards considered:
1. GRAS (generally recognized as safe) means that, given currently available information, the ingredient is considered safe Nothing is entirely safe Safe = a “low incidence of adverse reactions or significant
side effects under adequate directions for use and warnings against unsafe use as well as low potential for harm which may result from abuse”
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC RegulationOTC Regulation
2. GRAE (generally recognized as effective) = a reasonable expectation that the pharmacological effect of the drug will provide clinically significant relief of the type claimed in a significant proportion of the target population
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC LabelingOTC Labeling
3. GRAHL (generally recognized as honestly labeled) More than 300,000 OTC products on the
market contain fewer than 1,000 total active ingredients now reviewed in over 80 therapeutic classes. Those that the FDA has classified as safe and
effective
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC LabelingOTC Labeling
Layout, headings, and topics are consistent, and language has been made clearer and more concise, with less medical terminology
Consistent labels make it easier for consumers to compare products
Uniform labeling standards were adopted in 1997 to reduce consumer confusion
OTC LabelingOTC Labeling
© 2011 McGraw-Hill Higher Education. All rights reserved.
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC vs. Prescription DrugsOTC vs. Prescription Drugs
1938 Food, Drug, and Cosmetic Act established a classification of drugs that can be sold only by prescription
Possible differences between OTC and prescription drugs Dosage: An OTC version of a drug may come in
smaller doses Chemicals: A prescription drug may contain a
chemical not allowed for OTC sale due to potential toxicity
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC vs. Prescription DrugsOTC vs. Prescription Drugs
FDA panels review products and may switch drugs to OTC status Examples of drugs switched to OTC status
include ibuprofen (analgesic), orlistat (weight-loss), and cetirizine (antihistamine)
Should there be a class of drugs between OTC and prescription? Pharmacist recommended?
© 2011 McGraw-Hill Higher Education. All rights reserved.
Examples of Psychoactive Examples of Psychoactive OTC DrugsOTC Drugs
Stimulants FDA allows stimulants to be sold to “help
restore mental alertness or wakefulness when experiencing fatigue or drowsiness”
Only ingredient allowed by FDA in OTC stimulants is caffeine
Combinations of caffeine and other stimulants (e.g., ephedrine) are not allowed
© 2011 McGraw-Hill Higher Education. All rights reserved.
Examples of Psychoactive Examples of Psychoactive OTC DrugsOTC Drugs
Weight-control products Phenylpropanolamine (PPA) was sold over
the counter by the late 1970s Combinations of PPA and caffeine sold for
a brief period before being banned in 1983 Concerns over effectiveness of PPA and
the safety of recommended dosage due to its effects on blood pressure
2000: FDA requested all companies to stop marketing products containing PPA
© 2011 McGraw-Hill Higher Education. All rights reserved.
Examples of Psychoactive Examples of Psychoactive OTC DrugsOTC Drugs
Weight-control products Additional products banned due to lack of
safety or effectivenessEphedrineBenzocaine-containing candies and gumsStarch blockersCholecystokinin (CCK)
Currently, one FDA-approved weight-control OTC drug: Orlistat (alli)
© 2011 McGraw-Hill Higher Education. All rights reserved.
Examples of Psychoactive Examples of Psychoactive OTC DrugsOTC Drugs
Sedatives and sleep aids Early OTC sedatives and sleep aids
acetylcholine receptor blocker scopolamine + antihistamine methapyrilene
FDA review panel eventually rejected scopolamine but accepted methapyrilene
Later methapyrilene was found to cause cancer in rats, so it was no longer classified as GRAS
Different antihistamines were then marketed, and brands changed active ingredients frequently
Currently, there are no approved OTC sedatives; OTC sleep aids contain antihistamines
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC Analgesics: Pain and OTC Analgesics: Pain and PeoplePeople
Anesthetics (“without sensibility”) reduce all types of sensation or block consciousness completely
Analgesics (“without pain”) reduce pain selectively without causing a loss of other sensations
Types of pain, based on place of origin Visceral pain from nonskeletal portions of the body
Relieved by opioids Somatic pain from muscle or bone
Relieved by aspirin and related products
About 35 percent of patients obtain pain relief from a placebo
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC Analgesics: OTC Analgesics: Acetylsalicylic Acid (Aspirin)Acetylsalicylic Acid (Aspirin)
Development Long historical use of teas and extracts of willow
and poplar bark for pain relief Active ingredient—salicylic acid—was identified,
synthesized, and mass-produced in the nineteenth century
Related compound—acetylsalicylic acid—was synthesized in 1898 by a Bayer Laboratories’ chemist; had fewer side effects 1899: Patented and released for prescription sale in the
form of a white powder 1915: Sold over the counter in tablet form
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC Analgesics: OTC Analgesics: Acetylsalicylic Acid (Aspirin)Acetylsalicylic Acid (Aspirin)
Therapeutic use1. Analgesic—effectively blocks mild-to-moderate
somatic pain Maximum pain relief occurs in about one hour; effect
lasts for up to four hours Especially effective for headache and musculoskeletal
pain
2. Antipyretic—reduces fever Does not lower body temperature in someone with
normal body temperature Causes vasodilation of peripheral blood vessels and
increased perspiration
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC Analgesics: OTC Analgesics: Acetylsalicylic Acid (Aspirin)Acetylsalicylic Acid (Aspirin)
Therapeutic use3. Anti-inflammatory—reduces swelling,
inflammation and soreness
Relatively low toxicity Absorbed from the stomach and intestines
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC Analgesics: OTC Analgesics: Acetylsalicylic Acid (Aspirin)Acetylsalicylic Acid (Aspirin)
Effects/Risks Increases bleeding time by inhibiting blood platelet
aggregation Can cause bleeding problems for surgical patients May prevent heart attacks and strokes by preventing clots in
high-risk patients Induces gastrointestinal bleeding Reye’s syndrome—rare but serious disease
Effects can include disorientation, personality changes, lethargy, coma, and death
CDC recommends that aspirin should not be given to anyone under age 20 who has a suspected viral illness such as cold, influenza, or chicken pox
Accidental poisonings and suicide attempts
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC Analgesics: OTC Analgesics: Acetylsalicylic Acid (Aspirin)Acetylsalicylic Acid (Aspirin)
Mechanism of action Prostaglandins are local-acting hormones
Released when cell membranes are injuredMediate pain in injured areas by sensitizing
neurons to stimulation
Aspirin inhibits two forms of the cyclooxygenase (COX) enzymeBlocks the synthesis of pain-causing
prostaglandins
Aspirin also acts on prostaglandins involved in heat regulation
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC Analgesics: OTC Analgesics: AcetaminophenAcetaminophen
Acetaminophen is closely related to phenacetin, a now banned pain reliever
Compared to aspirin: As effective in analgesic and antipyretic effects Less useful as an anti-inflammatory drug Causes less gastric bleeding
Overuse of acetaminophen can cause serious liver disorders Not safer than aspirin if recommended dose is
exceeded As of 2009, the FDA limited the maximum single
adult dose to 650 mg for OTC products
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC Analgesics: Ibuprofen OTC Analgesics: Ibuprofen and Other NSAIDsand Other NSAIDs
Ibuprofen is an aspirin-like analgesic and anti-inflammatory; it also inhibits COX enzymes
Potential side effects Nausea and stomach pain Liver damage (if taken in large amounts)
Class of drugs is known as nonsteroidal anti-inflammatory drugs (NSAIDs)
Originally available by prescription, but now also available over the counter
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC Cold and Allergy OTC Cold and Allergy RemediesRemedies
All-too-common cold Colds are viral infections, caused by
viruses in the rhinovirus or coronavirus families
Viruses damage or kill the cells they attack In the case of colds, the affected cells are
on the upper respiratory tract Symptoms include coughing, sneezing,
and production of fluid by the mucous membranes
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC Cold and Allergy OTC Cold and Allergy RemediesRemedies
All-too-common cold Most cold viruses enter the body through
the nose or eyes; they are usually transmitted via an infected person’s hands
Frequent handwashing is a good strategy to reduce the risk of contracting a cold
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC Cold and Allergy OTC Cold and Allergy RemediesRemedies
Treatment of cold symptoms—no cure Modern cold remedies contain three
common types of ingredientsAntihistamines for temporary relief of runny
nose and sneezing– Of questionable benefit for cold symptoms
Nasal decongestants for temporary relief of swollen nasal membranes
Analgesic-antipyretics for temporary relief of aches and pains and fever reduction
© 2011 McGraw-Hill Higher Education. All rights reserved.
OTC Cold and Allergy OTC Cold and Allergy RemediesRemedies
Allergy and sinus medications Rely mainly on antihistamines May also include an analgesic
© 2011 McGraw-Hill Higher Education. All rights reserved.
Choosing an OTC ProductChoosing an OTC Product
Most products contain one or more of only a small number of ingredients, in different combinations An informed consumer can understand a large
proportion of these products by being familiar with only a few drugs
Single ingredient medications may be preferable to combination products Avoid medication interactions and side effects of drugs
that are designed to treat symptoms you may not have
© 2011 McGraw-Hill Higher Education. All rights reserved.
Chapter 12Chapter 12
Dietary Supplements and Over-the-Counter
Drugs
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