BNF for Children (BNFC) 2018-2019

2.4bHypophosphataemia

ELECTROLYTES AND MINERALS›PHOSPHATES

Phosphate

lINDICATIONS AND DOSE

Hypophosphataemia|Hypophosphataemic rickets|

Osteomalacia

▶BY MOUTH USING EFFERVESCENT TABLETS

▶Neonate: 1 mmol/kg daily in 1 – 2 divided doses, dose can

be taken as a supplement in breast milk—caution

advised as solubility in breast milk is limited to 1. 2 mmol

in 100 mL if calcium also added, contact pharmacy

department for details.

▶Child 1 month–4 years: 2 – 3 mmol/kg daily in 2 – 4 divided

doses, dose to be adjusted as necessary, dose can be

taken as a supplement in breast milk—caution advised

as solubility in breast milk is limited to 1. 2 mmol in

100 mL if calcium also added, contact pharmacy

department for details; maximum 48 mmol per day

▶Child 5–17 years: 2 – 3 mmol/kg daily in 2 – 4 divided

doses, dose to be adjusted as necessary; maximum

97 mmol per day

▶BY INTRAVENOUS INFUSION

▶Neonate: 1 mmol/kg daily, dose to be adjusted as

necessary.

▶Child 1 month–1 year: 0. 7 mmol/kg daily, dose to be

adjusted as necessary

▶Child 2–17 years: 0. 4 mmol/kg daily, dose to be adjusted

as necessary

IMPORTANT SAFETY INFORMATION

Some phosphate injection preparations also contain

potassium. For peripheral intravenous administration

theconcentrationof potassium should not usually exceed

40 mmol/litre. The infusion solution should be

thoroughly mixed. Local policies on avoiding

inadvertent use of potassium concentrate should be

followed. The potassium content of some phosphate

preparations may also limit therateat which they may

be administered.

lCAUTIONS

GENERAL CAUTIONSCardiac disease.dehydration.

diabetes mellitus.sodium and potassium concentrations

of preparations

SPECIFIC CAUTIONS

▶With intravenous useAvoid extravasation.severe tissue

necrosis

lSIDE-EFFECTS

GENERAL SIDE-EFFECTS

▶Common or very commonDiarrhoea

▶Frequency not knownNausea

SPECIFIC SIDE-EFFECTS

▶With intravenous useAcute kidney injury.hypocalcaemia.

hypotension.metastatic calcification.oedema

▶With oral useAbdominal distress

SIDE-EFFECTS, FURTHER INFORMATIONDiarrhoea is a

common side-effect and should prompt a reduction in

dosage.

lRENAL IMPAIRMENT

Dose adjustmentsReduce dose.

MonitoringMonitor closely in renal impairment.

lMONITORING REQUIREMENTSIt is essential to monitor

closely plasma concentrations of calcium, phosphate,

potassium, and other electrolytes—excessive doses of

phosphates may cause hypocalcaemia and metastatic

calcification.

lDIRECTIONS FOR ADMINISTRATION

▶With intravenous useDilute injection with Sodium Chloride

0. 9 %or 0. 45 % or Glucose 5 %or 10 %. Administration rate

of phosphate should not exceed 0. 05 mmol/kg/hour. In

emergencies in intensive care faster rates may be used—

seek specialist advice.

lPRESCRIBING AND DISPENSING INFORMATIONPhosphate

Sandoz®contains sodium dihydrogen phosphate

anhydrous (anhydrous sodium acid phosphate) 1. 936 g,

sodium bicarbonate 350 mg, potassium bicarbonate

315 mg, equivalent to phosphorus 500 mg (phosphate

16. 1 mmol), sodium 468. 8 mg (Na+ 20. 4 mmol), potassium

123 mg (K+ 3. 1 mmol);Polyfusor NA®contains Na+

162 mmol/litre, K+ 19 mmol/litre, PO 43 - 100 mmol/litre;

non-proprietarypotassium dihydrogen phosphate injection

(potassium acid phosphate) 13. 6 % may contain 1 mmol/mL

phosphate, 1 mmol/mL potassium.

lPATIENT AND CARER ADVICE

Medicines for Children leaflet: Phosphate supplements for low

phosphate levelswww.medicinesforchildren.org.uk/phosphate-

supplements-low-phosphate-levels

lMEDICINAL FORMS

There can be variation in the licensing of different medicines

containing the same drug. Forms available from special-order

manufacturers include: infusion, solution for infusion

Effervescent tablet

CAUTIONARY AND ADVISORY LABELS 13

▶Phosphate Sandoz(HK Pharma Ltd)

Sodium dihydrogen phosphate anhydrous 1.936 gramPhosphate

Sandoz effervescent tablets| 100 tabletp£ 19. 39

Solution for infusion

▶Phosphate (Non-proprietary)

Potassium dihydrogen phosphate 136 mg per 1 mlPotassium

dihydrogen phosphate 13. 6 % (potassium 10 mmol/ 10 ml) solution for

infusion 10 ml ampoules| 10 ampouleP£ 80. 25 – £ 92. 69 DT =

£ 92. 69

Infusion

▶Phosphate (Non-proprietary)

Potassium dihydrogen phosphate 1.295 gram per 1 litre,

Disodium hydrogen phosphate anhydrous 5.75 gram per

1 litrePolyfusor NA phosphates infusion 500 ml bottles|

1 bottleP£ 5. 15

2.5 Potassium imbalance

2.5a Hyperkalaemia

Other drugs used for HyperkalaemiaCalcium gluconate,

p. 594 .Salbutamol, p. 156

ANTIDOTES AND CHELATORS›CATION

EXCHANGE RESINS

Calcium polystyrene sulfonate

lINDICATIONS AND DOSE

Hyperkalaemia associated with anuria or severe oliguria,

and in dialysis patients

▶BY MOUTH

▶Child: 0. 5 – 1 g/kg daily in divided doses; maximum 60 g

per day

▶BY RECTUM

▶Neonate: 0. 5 – 1 g/kg daily, irrigate colon to remove resin

after 8 – 12 hours.

▶Child: 0. 5 – 1 g/kg daily, irrigate colon to remove resin

after 8 – 12 hours; maximum 30 g per day

600 Fluid and electrolyte imbalances BNFC 2018 – 2019

Blood and nutrition

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