10
P A R T 1
Introduction to nursing pharmacology
have, they can produce the generic drugs more cheaply.
In the past, some quality-control problems were found
with generic products. For example, the binders used in
a generic drug might not be the same as those used
in the brand-name product. As a result, the way the
body breaks down and uses the generic drug may differ
from that of the brand-name product. In that case,
the bioavailability of the drug is different from that
of the brand name product.
It is often recommended that a drug be dispensed
in the generic form if one is available. This requirement
helps to keep down the cost of drugs and healthcare.
Some prescribers, however, specify that a drug prescrip-
tion be “dispensed as written” (DAW), that is, that the
brand-name product be used. By doing so, the prescriber
ensures the quality control and the action and effect
expected with that drug. These elements may be most
important in drugs that have narrow safety margins,
such as digoxin (
Lanoxin
), a heart drug, and warfarin
(
Coumadin
), an anticoagulant. The initial cost may be
higher, but some prescribers believe that, in the long
run, the cost to the individual will be less.
Orphan drugs
Orphan drugs
are drugs that have been discovered but
are not financially viable and therefore have not been
“adopted” by any drug company. Orphan drugs may be
useful in treating a rare disease or they may have poten-
tially dangerous adverse effects. Orphan drugs are often
abandoned after preclinical trials or phase I studies.
Some drugs in this book have orphan drug uses listed.
More information about orphan drugs, and current
listings, can be found at
/
pm-orphan-drugs.htm.
Over-the-counter drugs
Over-the-counter (OTC) drugs
are products that are
available without prescription for self-treatment of
a variety of complaints. Some of these agents were
approved as prescription drugs but later were found to
be very safe and useful for individuals without the need
of a prescription. Some were not rigorously screened and
tested by the current drug evaluation protocols because
they were developed and marketed before the current
laws were put into effect. Many of these drugs were
“grandfathered” into use because they had been used for
so long. The TGA is currently testing the effectiveness
of many of these products and, in time, will evaluate all
of them. Although OTC drugs have been found to be
safe when taken as directed, nurses and midwives should
consider several problems related to OTC drug use:
• Taking these drugs could mask signs and symptoms of
underlying disease, making diagnosis difficult.
• Taking these drugs with prescription medications
could result in drug interactions and interfere with
drug therapy.
• Not taking these drugs as directed could result in
serious overdoses.
Many people do not consider OTC drugs to be medi-
cations and therefore do not report their use. Nurses and
midwives must always include specific questions about
OTC drug use when taking a drug history and should
provide information in all drug-teaching protocols about
avoiding OTC drug use while taking prescription drugs.
KEY POINTS
■■
Generic drugs are drugs no longer protected by
patent and can be produced by companies other than
the one that developed them.
■■
OTC drugs are available without a prescription and
are deemed safe when used as directed.
■■
Orphan drugs are drugs that have been discovered
but are not financially viable because they have a
limited market or a narrow margin of safety. These
drugs may have then been adopted for development
by a drug company in exchange for tax incentives.
KEY POINTS
Schedule
Description
1
This schedule is left blank
2 Pharmacy
Substances available from
Medicine
pharmacies, or from people licensed
to sell these drugs
3 Pharmacist
Substances that require professional
Only Medicine advice but are available from a
pharmacist
4 Prescription
Substances that are prescribed by a
Only Medicine person permitted under state or
territory legislation to prescribe,
and available from a pharmacy by
prescription
5 Caution
Hazardous substances that are
available to the public but require
care with handling
6 Poison
Substances that are readily
available to the public but are
more hazardous, requiring strong
warnings
7 Dangerous
Substances that are highly harmful
Poison
and require special manufacture,
handling and use precautions
8 Controlled
Substances with potential for
Drug
dependence
9 Prohibited
Substances that are prohibited due
Substance
to the potential for abuse; use is
limited to approved medical or
scientific research purposes
Taken from Dempsey et al. p.748
■■
BOX 1.2
Uniform scheduling of drugs and
poisons in Australia
