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P A R T 3
Drugs acting on the immune system
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NSAIDs block prostaglandin synthesis at COX-1
and COX-2 sites. This blocks inflammation but also
blocks protection of the stomach lining, as well as the
kidneys’ regulation of water.
■■
There are many different NSAIDs. If one does not
work for a particular person, another one might.
■■
Paracetamol causes vasodilation and heat release,
lowering fever and working to relieve pain.
■■
Paracetamol can cause liver failure. It is found in
many OTC products. Teach people to avoid toxic
doses of paracetamol.
ANTIARTHRITIS AGENTS
Other drugs that are used to block the inflammatory
process include the antiarthritis drugs. Arthritis is a
potentially debilitating inflammatory process in the
joints that causes pain and bone deformities. Antiarthri-
tis drugs include the gold compounds, which are used
to prevent and suppress arthritis in selected people with
rheumatoid arthritis. The other antiarthritis drugs are
specifically used to block the inflammation and tissue
damage of rheumatoid arthritis (see Table 16.3).
G
old compounds
Some individuals with rheumatic inflammatory con-
ditions do not respond to the usual anti-inflammatory
therapies, and their conditions worsen despite weeks or
months of standard pharmacological treatment. Some of
these individuals respond to treatment with gold salts,
KEY POINTS
also known as
chrysotherapy
, in which gold is taken
up by macrophages, which then inhibit phagocytosis; it
is reserved for use in people who are unresponsive to
conventional therapy and can be very toxic. The gold
salts available for use include auranofin (
Ridaura
) and
sodium aurothiomalate (
Myocrisin
).
Therapeutic actions and indications
Chrysotherapy results in inhibition of phagocytosis
(see Figure 16.1). Because phagocytosis is blocked, the
release of lysosomal enzymes is inhibited and tissue
destruction is decreased. This action allows gold salts to
suppress and prevent some arthritis and synovitis. Gold
salts are indicated to treat selected cases of rheuma-
toid and juvenile rheumatoid arthritis in people whose
disease has been unresponsive to standard therapy (see
Table 16.3 for usual indications). These drugs do not
repair damage; they prevent further damage and so are
most effective if used early in the disease.
Pharmacokinetics
The gold salts are absorbed at varying rates, depending
on their route of administration. They are widely dis-
tributed throughout the body but seem to concentrate
in the hypothalamic–pituitary–adrenocortical (HPA)
system and in the adrenal and renal cortices. The gold
salts are excreted in urine and faeces. These drugs cross
the placenta and enter into breast milk. They have been
shown to be teratogenic in animal studies and should
not be used during pregnancy or breastfeeding. Barrier
contraceptives should be recommended to women of
childbearing age, and another method of feeding the
baby should be used if gold therapy is needed in a breast-
feeding woman.
Contraindications and cautions
Gold salts can be quite toxic and are contraindicated in
the presence of any known allergy to gold, uncontrolled
diabetes, congestive heart failure, severe debilitation,
renal or hepatic impairment, hypertension, blood
dyscrasias, recent radiation treatment, history of toxic
levels of heavy metals, and pregnancy or breastfeeding.
Adverse effects
A variety of adverse effects is common with the use of
gold salts, which are probably related to their deposition
in the tissues and effects at that local level: stomatitis,
glossitis, gingivitis, pharyngitis, laryngitis, colitis, diar-
rhoea and other GI inflammation; gold bronchitis and
interstitial pneumonitis; bone marrow depression; vagi
nitis and nephrotic syndrome; dermatitis, pruritus and
exfoliative dermatitis; and allergic reactions ranging
from flushing, fainting and dizziness to anaphylactic
shock.
Care considerations for
people receiving NSAIDs and related agents
Assessment: History and examination
(Refer to the section on salicylates for
implementation with rationale and evaluation.)
■
■
Assess for
contraindications or cautions
: known
allergies to any salicylates, NSAIDs or tartrazine;
pregnancy or breastfeeding; hepatic or renal
disease; cardiovascular dysfunction; hypertension;
and GI bleeding or peptic ulcer.
■
■
Assess for
baseline status before beginning therapy
and for any potential adverse effects
: presence of
any skin lesions; temperature; orientation, reflexes
and affect; pulse, blood pressure and perfusion;
respirations and adventitious sounds; liver
evaluation; bowel sounds; and FBC, liver and renal
function tests, urinalysis, stool guaiac and serum
electrolytes.
