2.2.2 Loop diuretics
To be initiated on paediatric cardiologist advice
- furosemide tablets 20mg, 40mg, 500mg, oral solution, 50mg/5mL:
- Birth-1 month, 500micrograms/kg-1mg/kg TWICE a day. (500micrograms/kg-1mg/kg ONCE a day if post conceptual age under 31 weeks)
- 1 month-12 years, 1-2mg/kg one to three times a day. Higher doses may be required in resistant oedema; maximum single dose, 6mg/kg/dose.
- 12-18 years, 20-40mg one to three times a day, increased in resistant oedema.
- Furosemide produces a dose–dependent diuresis within 1 hour if given orally or 30 minutes if given intravenously; duration of action, 6 to 8 hours. Half life is very variable in the neonatal period and may be up to 24hours in preterm infants.
- Furosemide 500mg tablets are scored and can be halved.
- Thiazide diuretics may be prescribed for the treatment of persistent
hyperinsulinaemic hypoglycaemia of infancy. See section 6.1.4 (b).
- In an intensive care setting, continuous infusion of furosemide may be given.
- In children no longer in nappies, time doses to minimize social disruption.
2.2.3 Potassium-sparing diuretics
- spironolactone tablets 25mg, 50mg, 100mg; suspension, 25mg/5mL.
- Birth-12 years, 500microgram/kg-1.5mg/kg twice a day.
- 12-18 years, 25-50mg twice a day. Doses up to 9mg/kg (max. 400mg daily) have been used in resistant ascites.
- amiloride tablets 5mg; liquid 5mg/5mL
- Birth-12 years, 100-200microgram/kg twice a day; max 20mg daily.
- 12-18 years, 5-10mg twice a day.
- Amiloride and spironolactone are weak diuretics with potassium–sparing properties, given with other diuretics if hypokalaemia is a problem; may take 2–3 days for full effect.
- Spironolactone is an aldosterone antagonist used for oedema in hepatic cirrhosis or heart failure, and primary hyperaldosteronism.
- Potassium–sparing diuretics should be used with caution in renal impairment.
- Children receiving spironolactone may need to have their potassium levels checked, particularly if also on an ACE inhibitor.
- Potassium sparing diuretics are usually prescribed short-term for patients with left/right shunts prior to surgical correction or in the post-operative period (for up to 6 weeks). They may be given long-term in patients with poor myocardial function.