Pharmacology legal stuff

1906: Federal Food and Drug Act

1906: Federal Food and Drug Act

Safe labeling of drugs & formation of the National Formulary &

USP, as government standard for drug literature.

1938: 1906 Act revised to create Federal Food, Drug, and Cosmetic Act, June 25, 1938

mandatory testing for safety prior to marketing!

Sherley Amendment to Food and Drug Act

prohibits fraudulent therapeutic claims.

Harrison Narcotic Act

Established legal term "narcotic".

1951 Durham-Humphrey Amendment of Food & Drug Act

established "legend" drugs ( must be prescribed) versus OTC/over the counter and also specified that narcotics, etc not be refilled without a new prescription.

1962 Kefauver-Harris Amendment

required that both safety & efficacy be proven prior to marketing new drug.

1970 Controlled Substance Act

established schedules of drugs according to abuse potential (I/1 = highest; V/5= lowest).

1983 Orphan Drug Act

enabled FDA to promote research and marketing of drugs used to treat rare disease.

1991 Accelerated Drug Approval

Regulations to speed up the FDA drug review process for investigational new drugs to treat life threatening diseases

U.S. Controlled Drug Schedule

SCHEDULE I DRUGS

Dispensed only with approved protocol

US Controlled Drug Schedule

Schedule II Drugs

Written prescription required within 24 hours.

•No prescription refills

US Controlled Drug Schedule

Schedule III Drugs

•Written or oral prescription

•No more than five refills in 6 months

•May lead to moderate or low physical dependence or high psychological dependence.

US Controlled Drug Schedule

Schedule IV Drugs

•Container must have warning label

•Written or oral prescription

•No more than five refills in 6 months

•May lead to moderate or low physical dependence or high psychological dependence

US Controlled Drug Schedule

Schedule V Drugs

•Written or OTC

•Varies with each state law

Pharmacology and Nursing Practice

The nurse's responsibilities include knowledge & understanding of:

What drug is ordered.

Why the drug has been prescribed for the client.

How the drug is supplied by the pharmacy.

How the drug is administered, including dose ranges.

What nursing process considerations r/t the drug apply to this patient.

Chemical Name

According to the drug's chemical composition and molecular structure. i.e. acetylsalicylic acid/ASA

Generic Name

• Nonproprietary name that is short & simple. It is not capitalized.

• Given by the United States Adopted Name Council (USAN)

• Drug formularies are maintained by the generic name.

i.e. aspirin

Trade Name

-Propriety name

-First letter is capitalized

-Indicates drug has a registered trademark

-Indicates the commercial use is restricted to the owner of the patent of the drug.

i.e. Bayer aspirin

Classification of Drugs: Therapeutic

describes what is being treated by the drug.

Classification of Drugs: Pharmacologic

Describes how the drug acts.

Drug Prototypes

The drug in which all others are compared

Pharmaceutics

study of how various dosage "forms" influence pharmacokinetic and pharmacodynamics properties of drugs.

Pharmacokinetics

study of what the body does to the drug

Pharmacodynamics

study of what the drug does to the body

Toxicology

Adverse Effects

Route

is very important with regard to rate of availability. Topical, Sublingual, Parenteral and Enteral are the routes

Pharmacokinetics: Absorption

Rate drug is absorbed from site of administration and extent to which it occurs

Bioavailibility

expresses the "quantity" extent of drug absorption.

Enteral route

Absorption occurs through gastric mucosa, small intestine, or rectum, and passes through the portal circulation into the liver

First Pass Effect

Metabolism in the liver and return to circulation is the

Percutaneous

(sublingual, buccal, vaginal) application to body surfaces and IV routes BYPASS the LIVER and go directly to site of action (NO FIRST-PASS EFFECT).

Parenteral

(IM, IV, SUBQ)-IV fastest then IM and finally subq; depends upon blood flow (heat will increase). Suspensions are slower to absorb (Bicillin).

METABOLISM(biotransformation)

results in transformation of drug into:

• Inactive metabolite

• More soluble compound

• Or more potent metabolite

The enzyme systems (cytochrome P-450) of the liver are the primary site

• Drugs as substrates

• Drugs as enzyme inhibitors

• Drugs as enzyme inducers

Half-Life

time it takes for one half of the original amount of drug taken to be removed from body

Rule of Thumb

when a drug is discontinued it takes approximately four half-lives before the agent is considered 'functionally" eliminated. (94% is eliminated).

Onset of Action

Time required for drug to begin to take effect

Peak Effect

Time it takes for the drug to take maximum effect

Peak

highest concentration of drug in blood

Trough:

Lowest concentration of drug in blood

Duration of Action

The length of time the drug concentration is sufficient to continue to be effective

Loading Dose

is a higher amount of drug, often given only once or twice to "prime" the bloodstream with a level sufficient to quickly induce a therapeutic response

Maintenance Dose

before plasma levels drop back toward zero, intermittent doses are given to keep the plasma drug concentration in the therapeutic range

therapeutic effect

Drug-induced change in normal physiologic function. A positive change in faulty physiologic system

Therapeutic Index

describes a drug's margin of safety.

the ratio of a drug's toxic level to the level that provides therapeutic effects

Mechanism of Action

(therapeutic effect) produced in several ways: Receptor Interaction, Enzyme Interaction, Nonspecific Interaction

Receptor

Selective joining of drug molecule with reactive sites on cell surface- "affinity"

• Agonists

• Antagonists

• Agonist-antagonists

Enzyme Interaction

Drug binds with enzyme to create a therapeutic effect (ie., ACE inhibitors for HTN).

Nonspecific Interactions

Direct cellular effect (cell wall destruction of some antibiotics; starvation of cells by oncology medications).

Acute

Drugs used to treat a disorder of sudden onset.

Maintenance

Drugs used to treat chronic conditions.

Supplemental

Drug used to maintain normal function.

Palliative

Drugs used to make client comfortable during a terminal illness.

Supportive

therapy maintains integrity of body functions while patient is recovering (ie., fluids & electrolytes, blood products).

Prophylactic

drugs used to prevent a disease.

Empiric

Drugs used to treat a symptom of an illness

Side Effects

predictable, adverse drug reactions

Adverse Drug Reaction

unexpected, unintended, undesired or excessive response

Drug Concentration

measuring concentration in the body for therapeutic vs. toxic effect(Use peak & trough levels)

Idiosyncratic Reactions

not a result of a known pharmacologic property of drug (G6PD deficiency)

Teratogenic Effect

causes structural defects in unborn fetus

Mutagenic Effect

permanent changes in genetic composition of living organism

Carcinogenic Effect

can cause cancer particularly when taken over extended period of time

Drug Interactions

When action of one drug is altered by a second drug

ADDITIVE

two drugs with similar effect given together so each can be given in smaller doses

SYNERGISTIC

effect greater than that of each given individually.