8
P A R T 1
Introduction to nursing pharmacology
the lack of a cure. All literature associated with these
drugs indicates that long-term effects and other infor-
mation about the drug may not yet be known.
In addition to the drug lag issue, there also are
concerns about the high cost of drug approval. In 2011,
Morgan et al.
published a systematic review on the costs
of drug development. These authors found that the
estimated cost of taking a chemical from discovery to
marketing as a drug could be as high as $US 1.8 billion.
Because of this kind of financial investment, pharmaceu-
tical companies are unwilling to risk approval of a drug
that might cause serious problems and prompt lawsuits.
Phase IV studies
After a drug is approved for marketing, it enters a phase
of continual evaluation, or
phase IV study
. Prescribers
are obligated to report to the TGA any untoward or
unexpected adverse effects associated with drugs they
are using, and the TGA continually evaluates this infor-
mation. Some drugs cause unexpected effects that are
not seen until wide distribution occurs. Sometimes, those
effects are therapeutic. For example, individuals taking
the antiparkinsonism drug amantadine (
Symmetrel
)
were found to have fewer cases of influenza than other
people, leading to the discovery that amantadine is an
effective antiviral agent.
In other instances, the unexpected effects are danger-
ous. In 1997, the diet drug dexfenfluramine (
Ponderax
)
was removed from the market only months after its
release because people taking it developed serious heart
problems. In 2004, the drug company Merck withdrew
its cyclooxygenase-2 (Cox-2) specific non-steroidal
anti-inflammatory drug rofecoxib (
Vioxx
) from the
market when post-marketing studies seemed to show a
significant increase in cardiovascular mortality in indi-
viduals who were taking the drug. These problems were
not seen in any of the premarketing studies of the drug.
The effects were only seen with a much wider use of the
drug after it had been marketed.
KEY POINTS
■■
The TGA carefully regulates the testing and approval
of all drugs in Australia.
■■
To be approved for marketing, a drug must pass
through animal testing, testing on healthy humans,
selective testing on people with the disease being
treated and then broad testing on people with the
disease being treated.
LEGAL REGULATION OF DRUGS
The Therapeutic Goods Administration (TGA), a
division of the Commonwealth Department of Health
KEY POINTS
and Ageing, is responsible for administering the provi-
sions of the Therapeutic Goods Act 1989 in Australia
that regulates the manufacture, availability and supply
of drugs. Each state and territory also has Acts and
Regulations that deal with control and administration
of drugs. In most cases, the strictest law is the one that
prevails. Nurses and midwives should become familiar
with the rules and regulations in the area in which they
practise. They have a professional responsibility to be
informed of the legislation underpinning administration
and supply of drugs.
MEDSAFE is New Zealand’s Medicines and
Medical Devices Safety Authority. MEDSAFE is a
business unit of the Ministry of Health (Acts and Regu
lations; Medicine Management) and is the authority
responsible for the regulation of therapeutic products in
New Zealand. This includes medicines, related products,
herbal medicines, medical devices, controlled drugs used
as medicines, etc. through the Medicines Act 1981 and
Regulations 1984, and parts of the Misuse of Drugs Act
1975 and Regulations 1977. The overall objective of
these Acts is to ensure the quality, safety and efficacy
of therapeutic goods, including medicines and medical
devices, available to the Australian and New Zealand
public.
The Australian and New Zealand Governments are
currently working to harmonise the regulatory arrange-
ments for therapeutic products between both countries.
Both governments signed a Treaty in Wellington in
December 2003 to establish a single, bi-national agency
to regulate therapeutic products, including medical
devices and prescription medicines, and over-the-
counter, complementary and alternative medicines.
Transition to the new agency, Australia New Zealand
Therapeutic Products Agency (ANZTPA) is underway.
This agency will eventually replace the Australian TGA
and the New Zealand MEDSAFE, will be accounta-
ble to both Australian and New Zealand Governments
and will have a fully functional office in both countries.
Under the joint Australia–New Zealand therapeutic
products agency (the joint agency), products represented
as being for therapeutic use are to be regulated as thera-
peutic products. This includes complementary medicines
such as herbal, vitamin and mineral supplements, other
nutritional supplements, traditional medicines and
aromatherapy oils. Table 1.4 provides a summary of Aus-
tralian and New Zealand legislation around medications.
Safety during pregnancy
As part of the standards for testing and safety, the TGA
requires that each new drug be assigned to a pregnancy
category (Box 1.1). The categories indicate a drug’s
potential or actual teratogenic effects, thus offering
guidelines for use of that particular drug in pregnancy.
Research into the development of the human fetus,
