lactate 25 mmol/litre;Volplex®contains succinylated
gelatin (modifiedfluid gelatin, average molecular weight
30 000) 40 g( 4 %), Na+ 154 mmol, Cl- 125 mmol/litre.lMEDICINAL FORMS
There can be variation in the licensing of different medicines
containing the same drug.
Infusion
▶Gelaspan(B.Braun Medical Ltd)
Gelatin 40 mg per 1 mlGelaspan 4 % infusion 500 ml Ecobags|
1 bagP£ 5. 95 (Hospital only)
▶Gelofusine(B.Braun Medical Ltd)
Gelatin 40 mg per 1 mlGelofusine 4 % infusion 1 litre Ecobags|
1 bagP£ 9. 31
Gelofusine 4 % infusion 500 ml Ecobags| 1 bagP£ 4. 97
▶Geloplasma(Fresenius Kabi Ltd)
Gelatin 30 mg per 1 mlGeloplasma 3 % infusion 500 ml Freeflex bags
| 20 bagPs
▶Isoplex(Kent Pharmaceuticals Ltd)
Gelatin 40 mg per 1 mlIsoplex 4 % infusion 500 ml bags|
10 bagP£ 75. 00 (Hospital only)
▶Volplex(Kent Pharmaceuticals Ltd)
Gelatin 40 mg per 1 mlVolplex 4 % infusion 500 ml bags|
10 bagP£ 47. 00 (Hospital only)2.3 Magnesium imbalance
Magnesium
Magnesium is an essential constituent of many enzyme
systems, particularly those involved in energy generation;
the largest stores are in the skeleton.
Magnesium salts are not well absorbed from the
gastrointestinal tract, which explains the use of magnesium
sulfate p. 597 as an osmotic laxative.
Magnesium is excreted mainly by the kidneys and is
therefore retained in renal failure, but significant
hypermagnesaemia(causing muscle weakness and
arrhythmias) is rare.Hypomagnesaemia
Since magnesium is secreted in large amounts in the gastro-
intestinalfluid, excessive losses in diarrhoea, stoma or
fistula are the most common causes ofhypomagnesaemia;
deficiency may also occur as a result of treatment with
certain drugs. Hypomagnesaemia often causes secondary
hypocalcaemia (with which it may be confused), particularly
in neonates, and also hypokalaemia and hyponatraemia.
Symptomatichypomagnesaemiais associated with a deficit
of 0. 5 – 1 mmol/kg. Magnesium is given initially by
intravenous infusion or by intramuscular injection of
magnesium sulfate; the intramuscular injection is painful.
Plasma magnesium concentration should be measured to
determine the rate and duration of infusion and the dose
should be reduced in renal impairment. To prevent
recurrence of the deficit, magnesium may be given by mouth
in divided doses, but there is limited evidence of benefit.
Magnesium aspartate below powder for oral solution is
available as a licensed preparation.Arrhythmias
Magnesium sulfate injection has also been recommended for
the emergency treatment ofserious arrhythmias, especially in
the presence of hypokalaemia (when hypomagnesaemia may
also be present) and when salvos of rapid ventricular
tachycardia show the characteristic twisting wave front
known astorsade de pointes.2.3a Hypomagnesaemia
ELECTROLYTES AND MINERALS›MAGNESIUM
Magnesium aspartate
lINDICATIONS AND DOSE
Treatment and prevention of magnesium deficiency
▶BY MOUTH
▶Child 2–3 years: 4. 5 mmol daily, given as one level 5 mL
spoonful ofMagnaspartate®powder.
▶Child 4–9 years: 4. 5 mmol daily, given as a 5 mL level
spoonful ofMagnaspartate®powder, alternatively
10 mmol daily, given as 1 sachet ofMagnaspartate®
powder.
▶Child 10–17 years: 10 mmol daily, given as 1 sachet of
Magnaspartate®powder.lCONTRA-INDICATIONSDisorders of cardiac conduction
lINTERACTIONS→Appendix 1 : magnesium
lSIDE-EFFECTS
▶UncommonDiarrhoea.faeces soft
▶Rare or very rareFatigue.hypermagnesaemia
▶Frequency not knownGastrointestinal irritation
SIDE-EFFECTS, FURTHER INFORMATIONSide-effects
generally occur at higher doses; if side-effects (such as
diarrhoea) occur, consider interrupting treatment and
restarting at a reduced dose.
OverdoseSymptoms of hypermagnesaemia may include
nausea, vomiting,flushing of the skin, thirst, hypotension
due to peripheral vasodilatation, drowsiness, confusion,
loss of tendon reflexes and respiratory depression due to
neuromuscular blockade, slurred speech, double vision,
muscle weakness, bradycardia, cardiac arrhythmias, coma,
and cardiac arrest.
lRENAL IMPAIRMENTAvoid in severe impairment
(estimated glomerularfiltration rate less than
30 mL/minute/ 1. 732 ).
lDIRECTIONS FOR ADMINISTRATIONDissolve sachet
contents in 50 – 200 mL water, tea or orange juice and take
immediately.
lPRESCRIBING AND DISPENSING INFORMATION
Magnaspartate®contains magnesium aspartate 6. 5 g
( 10 mmol Mg^2 +)/sachet.
lPATIENT AND CARER ADVICEPatients and carers should be
given advice on how to administer magnesium aspartate
powder.lMEDICINAL FORMS
There can be variation in the licensing of different medicines
containing the same drug. Forms available from special-order
manufacturers include: powder
Powder
EXCIPIENTS:May contain Sucrose
▶Magnaspartate(KoRa Healthcare)
Magnesium (as Magnesium aspartate) 243 mgMagnaspartate
243 mg (magnesium 10 mmol) oral powder sachets| 10 sachetP
£ 8. 95 DT = £ 8. 95Magnesium glycerophosphate 24-Oct-2017
lINDICATIONS AND DOSE
Hypomagnesaemia
▶BY MOUTH
▶Child 1 month–11 years:Initially 0. 2 mmol/kg 3 times a
day, dose to be adjusted as necessary, dose expressed
as Mg(^2) +
596 Fluid and electrolyte imbalances BNFC 2018 – 2019
Blood and nutrition
9