Pharmacology and the Study of Drugs
a. Drug
i. A chemical which alters an organism’s function or processes
1. oxygen
2. alcohol
3. heparin
4. epinephrine
5. vitamins
b. Pharmacology
i. the study of drugs (chemicals), including their origin,
properties, and interactions with living organisms
c. Pharmacy
i. The preparation and dispensing of drugs
d. Pharmacognosy
i. The identification of sources of drugs, from plants and
e. Pharmacogenetics
i. The study of the interrelationship of genetic differences and
drug effects
f. Therapeutics
i. The art of treating disease with drugs
g. Toxicology
i. The study of toxic substances and their pharmacological
actions, including antidotes and poison control
Legislation Affecting Drugs
a. See text, page 3, Box 1-1
b. Qualified medical practitioners who prescribe, dispense, or
administer drugs must comply with federal and state laws
governing the manufacture, sale, possession, administration, and
dispensing and prescribing of drugs.
c. All drugs available for legal use are controlled by the Federal Food,
Drug and Cosmetic Act. This law protects the public by insuring the
purity, strength, and composition of food, drugs, and cosmetics. It
also prohibits the movement, in interstate commerce, of
adulterated and misbranded food, drugs, devices, and cosmetics.
d. Enforcement of this act is the responsibility of the Food and Drug
Administration (FDA), which is part of the Department of Health and
Human Services (HHS) of the US Government.
e. The Controlled Substance Act of 1970 controls the manufacture,
importation, compounding, selling, dealing in, and giving away of
drugs that have the potential for addiction and abuse. These drugs
are known as controlled substances (opium, cocaine, narcotics,
stimulants, and depressants). The act is enforced by the Drug
Enforcement Administration (DEA). Under federal law, medical
practitioners who prescribe, administer, or dispense controlled
substances must register with the DEA and physicians are required
to renew their registration annually.
f. Drug Schedules: controlled substances are classified according to
five drug schedules
i. Schedule I: have a high potential for abuse and are not
accepted for medical use within the US
ii. Schedule II: have a high potential for abuse (psychological or
physical dependency) but do have an accepted medical use
within the US
iii. Schedule III: have a low to moderate potential for physical
dependency with a high potential for psychological
iv. Schedule IV: have a low potential for abuse which may lead
to limited physical or psychological dependency
v. Schedule V: have the lowest abuse potential of the controlled
substances consisting of antitussives and antidiarrheals
vi. Examples of drugs
Schedule I
Heroin, LSD, marijuana, mescaline, peyote, and
Schedule II
Amobarbital, amphetamine, cocaine, codeine,
hydromorphone, opium, meperidine, methadone,
morphine, Nembutal, pentobarbital, percodan,
Quaalude, secobarbital, and Marinol
Schedule III
Barbituates, drug combinations including codeine and
paregoric, gleutethimide, mazindol, methyprylon,
phenmetrazine, and amphetamine like compounds
Schedule IV
Chloral hydrate, diazepam, meprobamate,
paraldehyde, Phenobarbital, Librium, valium, darvon
Schedule V
Lomotil, donnagel, drugs containing low-strength
codeine (Actifed with codeine)
g. Federal law requires that all controlled substances be kept separate
from other drugs under a double lock. The medicine nurse or
charge nurse keeps the narcotic key during the shift. A separate
record book is kept for narcotic counts which are done and shift
change by an oncoming and off going nurse who both count the
meds and sign for accuracy or discrepancy.
Naming Drugs
a. Chemical name
i. The name indicating the drug's chemical structure
b. Code name
i. A name assigned by a manufacturer to an experimental
chemical that shows potential as a drug
1. SCH 1000 – ipratropium bromide
c. Generic name
i. The name assigned by U.S. Adopted Name Council when the
chemical appears to have therapeutic use and the
manufacturer wishes to market the drug
ii. The name is loosely based on the chemical structure
iii. Drugs in the same class end in the same syllable
iv. Written in lower case
d. Official name
i. The generic name becomes the official name when it is
approved by the United States Pharmacopeia-National
Formulary (USP-NF)
e. Trade name
i. The brand name given by a manufacturer
ii. The name is capitalized and may have a trademark (®)
Sources of Drug Information
a. United States Pharmacopeia-National Formulary (USP-NF)
i. Gives standards for drugs in US
ii. Contains fully approved drugs (by FDA) and formulas for
drugs and mixtures
b. AMA Drug evaluations
i. Contains new drugs not officially in USP yet (in trials, animal
and human)
c. Physician’s Desk Reference (PDR)
i. Prepared by manufacturers of drugs
ii. Includes descriptive color charts for durg identification, names
of manufacturers, and general drug actions
iii. Published annually
Sources of Drugs
a. Animal
i. thyroid hormone
ii. insulin
iii. pancreatic dornase
b. Plant
i. atropine
ii. digitalis
iii. curare
c. Mineral
i. magnesium sulfate
ii. mineral oil
d. Chemical synthesis
i. manufactured in the laboratory
Process of Drug Approval in the United States
a. Isolation and identification of a chemical with the potential for
useful physiologic effects
i. The exact structure and physical and chemical characteristics
of an active ingredient are established
b. Animal Studies
i. general effects on the organism
ii. effects on specific organs
iii. toxicology studies for
1. mutagenicity – mutations
2. teratogenicity - potential to damage a fetus in utero
3. effect on fertility
4. carcinogenicity - causing cancer
c. Investigational New Drug (IND) approval
i. An application is filed with the FDA which contains
1. all information previously gathered
2. plans for human studies
ii. Three years for human studies
1. Phase I - small group of healthy volunteers
2. Phase II - small group of subjects with the disease
3. Phase III - large multicenter studies to establish safety
and efficacy
d. New Drug Application (NDA) is filed with the FDA
i. Upon approval, the drug is released for general clinical use
e. This an involved, lengthy and expensive process
i. The process can take an average of 13 - 15 years
ii. The average cost is $350 million dollars
iii. 1 in 10,000 identified chemicals will reach general clinical use
f. Food and Drug Administration New Drug Classification System
i. Chemical/Pharmaceutical Standing
1. New chemical entity
2. New salt form
3. New dosage form
4. New combination
5. Generic drug
6. New indication
ii. Therapeutic Potential
1. A=Important therapeutic gain over other drugs
2. AA=Important therapeutic gain, indicated for a patient
with acquired immunodeficiency syndrome (AIDS); fasttrack
3. B=Modest therapeutic gain
4. C=Important options; little or no therapeutic gain
g. Orphan Drugs
i. A drug or biological product for the diagnosis or treatment of
a rare disease (< 200,000 persons)
ii. A drug or biological product used with no reasonable
expectation of recovering the cost of drug development
The Prescription
a. The written order for a drug, along with any specific instructions
fort compounding, dispensing, and taking the drug
b. Parts of the prescription
i. Patient’s name, address, and date
ii. Superscription - Rx (meaning “recipe” or “take thou”) directs
the pharmacist to take the drug listed and prepare the
iii. Inscription – lists the name and quantity of the drug being
iv. Subscription – the directions to the pharmacist on preparing
the medication
v. Transcription - Sig (signa) means “write”. The information the
pharmacist writes on the label of the medications as
instructions to the patient.
vi. Name of the prescriber – the physician’s signature
c. Over-the-Counter Drugs
i. Drugs available without a prescription
ii. The strength and amount per dose may be less than with a
prescription formulation
iii. OTC drugs can be hazardous in normal amounts if their
effects are not understood and can be taken in large
d. Generic Substitution in Prescriptions
i. A physician can indicate to the pharmacist that generic
substitution is permitted in the filling of the prescription
ii. The manufacturer of the generic substitute has not invested
the considerable time and money required to develop an
original drug product
iii. The generic substitute will be less expensive to the consumer
e. Common abbreviations used for prescriptions
f. FDA Use-in-Pregnancy Ratings
i. The FDA pregnancy categories are based on the degree to
which available information has ruled out risk to the fetus,
balanced against the drug’s potential benefits to the patient
Adequate, well-controlled studies in pregnant women have not shown an
increased risk of fetal abnormalities to the fetus in any trimester of
Animal studies have revealed no evidence of harm to the fetus, however,
there are no adequate and well-controlled studies in pregnant women.
Animal studies have shown an adverse effect, but adequate and wellcontrolled studies in pregnant women have failed to demonstrate a risk to
the fetus in any trimester.
Animal studies have shown an adverse effect and there are no adequate
and well-controlled studies in pregnant women.
No animal studies have been conducted and there are no adequate and
well-controlled studies in pregnant women.
Adequate well-controlled or observational studies in pregnant women
have demonstrated a risk to the fetus.
However, the benefits of therapy may outweigh the potential risk. For
example, the drug may be acceptable if needed in a life-threatening
situation or serious disease for which safer drugs cannot be used or are
Adequate well-controlled or observational studies in animals or pregnant
women have demonstrated positive evidence of fetal abnormalities or
The use of the product is contraindicated in women who are or may
become pregnant