806
P A R T 9
Drugs acting on the renal system
TABLE 51.1
DRUGS IN FOCUS Diuretics (continued)
Drug name
Dosage/route
Usual indications
Potassium-sparing diuretics
amiloride (Kaluril)
5–10 mg/day PO to maximum 20 mg/day
Adjunctive treatment of oedema caused
by HF, liver disease or renal disease;
hypertension; hyperkalaemia; and
hyperaldosteronism
Special consideration:
Not for use in
children
eplerenone (Inspra)
25 mg/day PO titrated to 50 mg/day PO within
4 weeks
Risk reduction in people with heart failure
and left ventricular impairment following
AMI
spironolactone
(Aldactone)
100–200 mg/day PO for oedema;
100–400 mg/day PO for hyperaldosteronism;
50–100 mg/day PO for hypertension
Paediatric: 3.3 mg/kg per day PO
Adjunctive treatment of oedema caused
by HF, liver disease or renal disease;
hypertension; hyperkalaemia; and
hyperaldosteronism
Special consideration:
Can be used
in children with careful monitoring of
electrolytes
triamterene (Hydrene)
100 mg PO mané or b.d
Adjunctive treatment of oedema caused
by HF, liver disease or renal disease;
hypertension; hyperkalaemia; and
hyperaldosteronism
Special consideration:
Not for use in
children
Osmotic diuretics
glucose (generic)
IV; depends on individual
Treatment of oedematous states, including
cerebral oedema
mannitol (Osmitrol)
50–100 g IV for oliguria; 1.5–2 g/kg IV to
reduce intracranial pressure; dose not
established for children <12 years
Treatment of elevated intracranial pressure,
acute renal failure, acute glaucoma; also
used to decrease intracranial pressure,
prevent oliguric phase of renal failure,
and to promote movement of toxic
substances through the kidneys
BOX 51.1
Drug therapy across the lifespan
Diuretic agents
CHILDREN
Diuretics are often used in children to treat oedema
associated with heart defects, to control hypertension,
and to treat oedema associated with renal and pulmonary
disorders.
Hydrochlorothiazide has established paediatric
dosing guidelines. Frusemide is often used when
a stronger diuretic is needed; care should be taken
not to exceed 6 mg/kg per day when using this drug.
Ethacrynic acid may be used orally in some situations
but should not be used in infants. Bumetanide, although
not recommended for use in children, may be used for
children who are taking other ototoxic drugs, including
antibiotics, and may cause less hypokalaemia, making it
preferable to frusemide for children also taking digoxin.
Spironolactone is the only potassium-sparing diuretic that
is recommended for use in children, but, as with adults,
it should not be used in the presence of severe renal
impairment.
Because of the size and rapid metabolism of children,
the effects of diuretics may be rapid and adverse effects
may occur suddenly.The child receiving a diuretic
should be monitored for serum electrolyte changes; for
evidence of fluid volume changes; for rapid weight gain
or loss, which could reflect fluid volume; and for signs of
ototoxicity.
ADULTS
Adults may be taking diuretics for prolonged periods
and need to be aware of the signs and symptoms of
fluid imbalance to report to their healthcare provider.
Adults receiving chronic diuretic therapy should weigh
themselves on the same scale, in the same clothes, and at
the same time each day to monitor for fluid retention or
sudden fluid loss.They should be alerted to situations that
could aggravate fluid loss, such as diarrhoea, vomiting,
or excessive heat and sweating, which could change
their need for the diuretic.They should also be urged to
maintain their fluid intake to help balance their body’s
compensatory mechanisms and to prevent fluid rebound.
