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Chapter 14 Prescription Drugs, Over-the-Counter Drugs, and Dietary Supplements

Chapter 14 Prescription Drugs, Over-the-Counter Drugs, and Dietary Supplements

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Chapter 14

Prescription Drugs,Over-the-Counter Drugs,and Dietary Supplements

Categories ofMedicinal Products

Three categories of medicinal substances are available for purchase:

•prescription drugs•over-the-counter (OTC) drugs•dietary supplements

Categories ofMedicinal Products

The U.S. Food and Drug Administration (FDA) sets standards of safety, effectiveness, and honesty in labeling for prescription drugs and OTC drugs.

Dietary supplements are not regulated as drugs.

Cosmetics are also regulated by the FDA.“articles intended to be rubbed, poured, sprinkled, or sprayed on, introduced into, or otherwise applied to the human body...for cleansing, beautifying, promoting attractiveness, or altering the appearance"

What is a drug?Drug: A chemical substance which, when taken intothe body, alters the structure or functioning of the body in some way.

Problems with this definition?

…excluding those nutrients considered to be related to normal functioning. (whether the substance in question has been intended to be used primarily as a way of inducing abodily or psychological change; p. 5)

Is toothpaste a drug?

Is deodorant a drug?

Is shampoo a drug?

Is skin moisturizer a drug?

Scents—Drugs or Not?(does it make sense?)

Perfumes?

Aromatherapy?

Room deodorizers?

How the Regulation of Prescription and OTC Drugs Began

No regulation prior to 1906; “snake oil” salesmen abounded

1906 Pure Food and Drug Actensured purity and consistency of drugsactive ingredients must be identified on label

1938 Food Drug and Cosmetic Actingredients in drugs and cosmetics must be proven safebasis of modern food and drug regulations

1962 Kefauver-Harris Amendmentdrug must be proven safe and effective

_________is the basis for all present-day U.S. food and drug laws.

A. The Pure Food and Drug Act of 1906B. The Dietary Health and Education Act of 1994C. The Federal Food, Drug, and Cosmetic Act of 1938D. The Kefauver-Harris Amendment of 1962E. The Dietary Supplement Health and Education Act

of 1994

Procedures for Approving Prescription and OTC Drugs

1. animal studiesdetermine safety limits and relative toxicity

2. clinical trialsa. healthy human volunteers

Phase 1: establish drug safety b. patients

Phase 2: establish effectiveness for therapeutic use

Phase 3: identify optimal doses and dosing regimen; identify side effects

LD 50,birth defects

long-term toxicity

safety

therapeutic effectiveness

dosing regimen,side effects,usage—final tweaking

(or more)

A serious problem in the development and testing of many drugs is that interactions with other drugs are not tested and may be unpredictable.There may also be unanticipated long-term effects.

Patent clock begins to run Marketing of drug

In Phase 1 clinical trials, __________.A. certain pharmacological questions are answeredB. clinical samples are not involvedC. safe dosage levels are determinedD. drug effectiveness is not consideredE. all of the above

Procedures for Approving Prescription Drugs

Very few new compounds are eventually approved by the FDA for marketing as new prescription drugs.

The process often takes several years.

Patent clock (20 years) begins to run when Phase 1 clinical trials begin.

drug companies must recover research costs

may introduce “new” drugs with minor differences to obtain a new patent (e.g. time-release version)

may obtain approval to market drug OTC (e.g. Tylenol, Benadryl, Claritin)

Table 14.2

Procedures for Approving OTC Drugs

Since 1962, all OTC drugs have been required by the FDA to be Generally Recognized As

Safe (GRAS)

Effective (GRAE)

Honestly Labeled (GRAHL)

Approval of OTC drugs must follow the NDA process or, more commonly, conform to existing drug monographs.

Table 14.3

Are FDA-ApprovedDrugs Safe?

Prescription and OTC drugs are FDA-approved for use when taken in the recommended dosages and under the recommended circumstances, their misuse can result in medical emergencies and fatalities.Prescription drug misuse, whether intentional or unintentional (prescription errors), is a growing public health problem as the number of available medications increases.

There have been several recent instances of drugs with similar names being incorrectly dispensed

Are FDA-ApprovedDrugs Safe?

ER visits involving prescription drugs far fewer than those involving illegal drugs

Prescription drugs are often the choice for suicide attempts

Most ER visits involving prescription drugs are for polydrug use, usually alcohol (e.g. benzodiazepines and other depressants; OxyContin and other opiates)

Doctor-shopping, lax medical oversight of multiple-prescription users (often the elderly)

Which of the following best characterizes the FDA’s approach to approving drugs for the market?

A. speedB. empathyC. caution (safety)D. need for the drugE. likely profitability of the drug

Major OTC Analgesic Drugs

OTC analgesic drugs

acetylsalicylic acid (aspirin),

acetaminophen (e.g. Tylenol)

ibuprofen (e.g. Advil, Motrin)

naproxen (e.g. Aleve)

Major OTC Analgesic Drugs aspirin, ibuprofen and naproxen are anti-inflammatory (non-steroidal anti-inflammatory drugs; NSAIDs)

acetaminophen is not anti-inflammatory

aspirin and acetaminophen are both anti-pyretic (fever-reducing)

long duration of effect makes naproxen effect for relief of menstrual cramps

NSAIDs may interact with, and reduce the effectiveness of, SSRI antidepressants.

Major OTC Analgesic Drugs

Hazards include:

aspirin: gastrointestinal irritation, bleeding acetaminophen: bleeding, liver and kidney damage

especially troublesome with alcohol consumptionpotentially lethal

ibuprofen: kidney damage or failure

naproxen: gastrointestinal irritation

Analgesic Anti-Inflammatory

Anti-pyretic

Acetylsalicylic Acid(aspirin)

Acetaminophen(Tylenol)

Ibuprofen(Advil, Motren)

Naproxen Sodium(Aleve)

Other Major Classesof OTC Drugs

OTC sleep aids and cough-and-cold remedies are notable for their popularity and their potential for misuse.

sleep aids with an active ingredient of either diphenhydramine (e.g. Benadryl) or doxylamine succinate (e.g. Unisom).

these antihistamines are depressants that aretypically components of “P.M.” versions of cold medications

Other Major Classesof OTC Drugs

OTC sleep aids and cough-and-cold remedies are notable for their popularity and their potential for misuse.

antihistamines + alcohol additive

alcohol content increases abuse potential

pseudoephedrine used to make crystal methamphetaminealthough still OTC, sales are now monitored

dextromethorphan is a continuing drug abuseproblem (so-called “robo-tripping,” after “Robitussin”)

The Pharmaceutical Industry Today

Highly competitive marketadvertising in mass mediadiversification of productsprotection from generics

The Pharmaceutical Industry Today

Pressure to reduce priceshigh cost of drug researchuninsured and underinsured patientsmaintaining adequate supplies

problems regulating internet trafficking of prescription medicationscopycats masquerade as brand-name drugoften of foreign originmanufacturing unsupervised

problems of accuracy and purity

a vitamina mineralan herb or other botanicalan amino acida dietary substance for use by man to supplement the diet by increasing the total dietary intake (e.g., enzymes or tissues from organs or glands)a concentrate, metabolite, constituent or extract.

What is a Dietary Supplement?1994 Dietary Supplement Health and Education Act (DSHEA)

A dietary supplement is “a product taken by mouth that contains a ‘dietary ingredient’ intended to supplement the diet.

Dietary Supplements

A large number of dietary supplements are available to the public.

Unlike OTC preparations, dietary supplements are not evaluated by the FDA for safety or efficacy.

This lack of regulation should not be construed to tacit approval of either their use or safety. They may or may not be safe or effective and may interact with other drugs.

Therefore, considerable caution should be exercised when using them.

Which of the following is a dietary supplement? A. an analgesicB. a weight-loss aidC. an herbal formula to boost testosteroneD. a cough and cold remedy

Dietary supplements are considered foods, not drugs.

Under DSHEA, a firm is responsible for determining that the dietary supplements it manufactures or distributes are safe and that any representations or claims made about them are substantiated by adequate evidence to show that they are not false or misleading.

Pre-market review for safety data and other information is required.

Manufacturers need to register with the FDA pursuant to the Bioterrorism Act

Dietary Supplements

Dietary Supplements

What must appear on a label of a dietary supplement?

a descriptive name of the product stating that it is a "supplement" the name and place of business of the manufacturer, packer, or distributor a complete list of ingredients (active and inactive)the net contents of the product

Claims of medical benefits for supplements are often exaggerated and are difficult to verify because well-controlled scientific studies of their effectiveness are either nonexistent or incomplete.

Clearly, more scientific studies should be conducted to evaluate these supplements.

(Why AREN’T there more studies?)

Dietary Supplements

The FDAmonitors the marketplace for illegal products (products that may be unsafe or make false or misleading claims)

and obtains information frominspections of dietary supplement manufacturers and distributorsthe Internetconsumer and trade complaintsoccasional laboratory analyses of selected products adverse events associated with the use of supplements that are

reported to the agency.

Dietary Supplements

A product cannot make claims to be a treatment, prevention or cure for a specific disease or condition (only substances classified and regulated as drugs may do that).

Manufacturers MAY make health claims(links between a food substance and disease or a health-related condition)structure/function claims(intended benefits of using the product)nutrient content claims(amount of a nutrient or dietary substance in a product)

Dietary Supplements

Disclaimers are often provided to qualify claims

“This statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease”

Claims of medical benefits for supplements are often exaggerated and are difficult to verify because well-controlled scientific studies of their effectiveness are either nonexistent or incomplete.

Clearly, more scientific studies should be conducted to evaluate these supplements.

(Why AREN’T there more studies?)

Dietary Supplements

Cautionary notes:

active chemical constituents of dietary supplements need not be specifically identified

doses of active chemicals may vary by lot; actual dose will therefore vary

those taking supplements may fall victim to the “more must be better” thinking; e.g. pyridoxine (vitamin B6)

potential side effects need not be listed on the label

potential drug interactions need not be listed

Dietary Supplements