ADMINISTRATION ROUTES:
PO
ALTERNATIVE NAMES:
Spirotone, spironolactone
ICU INDICATIONS:
- Heart failure
- Essential hypertension
- Fluid overload
PRESENTATION AND ADMINISTRATION:
PO:
Tablets:
Spirotone 25mg and 100 mg tablets (pale orange)
Oral Liquid:
Spironolactone oral liquid 5 mg/mL
Note: crush tablets for NG administration
DOSAGE:
PO:
25-100 mg/day in single or divided doses
Increase to maximum 200 mg/day
DOSAGE IN RENAL FAILURE AND RENAL REPLACEMENT THERAPY:
Dose in renal impairment
| GFR (ml/min) | DOSE |
|---|---|
| <10 | do not use |
| 10-30 | do not use |
| >30-50 | 25 mg per day |
Dose in renal replacement therapy
| MODALITY | DOSE |
|---|---|
| CAPD | do not use |
| HD | do not use |
| CVVHDF | do not use |
DOSAGE IN PAEDIATRICS:
PO:
1 - 10 kg:
6.25 mg BD
11 - 20 kg:
12.5 mg BD
21 - 40 kg
25 mg BD
40 - 80 kg
25 mg TDS
Note: stated dose is total amount to give, not per kg
CLINICAL PHARMACOLOGY:
Spironolactone is a potassium sparing diuretic
CONTRAINDICATIONS:
- Hyperkalaemia
- Renal failure
WARNINGS:
Hyperkalaemia
Excessive potassium intake may cause hyperkalaemia in patients receiving spironolactone
PRECAUTIONS:
General:
See WARNINGS
Laboratory Tests:
No tests are required in addition to routine ICU tests; close monitoring of potassium and renal function are important
Drug/Laboratory Test Interactions:
Several reports of possible interference with digoxin radioimmunoassays by spironolactone, or its metabolites, have appeared in the literature. Neither the extent nor the potential clinical significance of its interference (which may be assay-specific) has been fully established.
IMPORTANT DRUG INTERACTIONS IN ICU:
ACE Inhibitors:
Concomitant administration of ACE inhibitors with potassium-sparing diuretics has been associated with severe hyperkalaemia.
Skeletal Muscle Relaxants, Nondepolarising:
Possible increased responsiveness to the muscle relaxant may result.
Lithium:
Lithium should not be given with diuretics as they reduce the renal clearance of lithium and increase the risk of lithium toxicity.
Nonsteroidal Anti-inflammatory Drugs (NSAIDs):
In some patients, the administration of an NSAID can reduce the diuretic, natriuretic, and antihypertensive effect of loop, potassium-sparing and thiazide diuretics. Combination of NSAIDs, has been associated with severe hyperkalaemia.
Digoxin:
Spironolactone has been shown to increase the half-life of digoxin. This may result in increased serum digoxin levels and subsequent digitalis toxicity.
ADVERSE REACTIONS:
Digestive:
Gastric bleeding, ulceration, gastritis, diarrhoea and cramping, nausea, vomiting
Endocrine:
Gynaecomastia, irregular menses or amenorrhea, postmenopausal bleeding
Haematologic:
Agranulocytosis
Hypersensitivity:
Fever, urticaria, maculopapular or erythematous cutaneous eruptions, anaphylactic reactions, vasculitis
Nervous System/Psychiatric:
Mental confusion, ataxia, headache, drowsiness, lethargy
Liver/Biliary:
A very few cases of mixed cholestatic/hepatocellular toxicity (including fatality), have been reported with spironolactone administration