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P A R T 2
Chemotherapeutic agents
Therapeutic actions and indications
The topical antifungal drugs work to alter the cell per-
meability of the fungus, causing prevention of replication
and fungal death (see Figure 11.1). They are indicated
only for local treatment of mycoses, including tinea
infections. See Table 11.2 for usual indications. (See also
Critical thinking scenario related to drug therapy.)
Pharmacokinetics
These drugs are not absorbed systemically and do not
undergo metabolism or excretion in the body.
Contraindications and cautions
Because these drugs are not absorbed systemically,
contraindications are limited to a known allergy to any
of these drugs and open lesions. Econazole can cause
intense, local burning and irritation and should be dis-
continued if these conditions become severe. Terbinafine
should not be used for longer than 4 weeks. This drug
should be stopped when the fungal condition appears to
be improved or if local irritation and pain become too
great to avoid toxic effects.
Adverse effects
When these drugs are applied locally as a cream, lotion or
spray, local effects include irritation, burning, rash and
swelling. When they are taken as a suppository or troche
(lozenge), adverse effects include nausea, vomiting and
hepatic dysfunction (related to absorption of some of the
drug by the GI tract) or urinary frequency, burning and
change in sexual activity (related to local absorption in
the vagina).
Prototype summary: Clotrimazole
Indications:
Treatment of oropharyngeal candidiasis
(troche); prevention of oropharyngeal candidiasis
in people receiving radiation or chemotherapy;
local treatment of vulvovaginal candidiasis (vaginal
preparations); topical treatment of tinea pedia,
tinea cruris and tinea corporis.
Actions:
Binds to sterols in the fungal cell
membrane, changing membrane permeability and
allowing leakage of intracellular components,
causing cell death.
Pharmacokinetics:
Not absorbed systemically;
pharmacokinetics is unknown.
Adverse effects:
Troche: nausea, vomiting, abnormal
liver function tests. Topical: stinging, redness,
urticaria, oedema. Vaginal: lower abdominal pain,
urinary frequency, burning or irritation in the
sexual partner.
CRITICAL THINKING SCENARIO
Poor nutrition and opportunistic infections
THE SITUATION
P.P., a 19-year-old woman and aspiring model, complains
of abdominal pain, difficulty swallowing and a very sore
throat. The strict diets she has followed for long periods
have sometimes amounted to a starvation regimen. In the
last 18 months, she has received treatment for a variety of
bacterial infections (e.g. pneumonia, cystitis) with a series of
antibiotics.
P.P. appears to be a very thin, extremely pale young
woman who looks older than her stated age. Her mouth
is moist, and small, white colonies that extend down
the pharynx cover the mucosa. A vaginal examination
reveals similar colonies. Cultures are performed, and it
is determined that she has mucocutaneous candidiasis.
Ketoconazole (
Nizoral
) is prescribed and P.P. is asked to
return in 10 days for follow-up.
CRITICAL THINKING
What are the effects of taking a variety of antibiotics on
the normal flora?
Think about the possible cause of the
mycosis
.
What happens to the immune system and to the skin and
mucous membranes when a person’s nutritional status
becomes insufficient?
How is P.P.’s chosen profession affecting her health? What
are the possible ramifications of suggesting that P.P.
change her profession or her lifestyle?
What are the important nursing implications for P.P.?
Think about how the nurse can work with P.P. to ensure
some compliance with therapy and a return to a healthy
state.
