Treatment of low electrolytes
| Electrolytes | Level | Initial prescribing action | Monitor |
| Phosphate | greater than 0.5 to 0.8mmol/L | No supplementation is required if dietary intake adequate | Check phosphate after 24 hours |
| 0.3 to 0.5 mmol/L |
Asymptomatic patients may not need to be treated. Oral: 2 Phosphate Sandoz® tablets daily. Via enteral feeding tube: dissolve tablet(s) in 50mL water. Stopping feed is not required. Intravenous: peripheral administration – 10mL Glycophos® diluted in 250mL glucose 5% or sodium chloride 0·9%. Infuse over 12 hours. Half above doses in patients with eGFR ≤30mL/min. |
Check potassium, phosphate an adjusted calcium every 24 hours. Supplement daily until phosphate more than 0.5mmol/L |
|
| Less than 0·3mmol/L |
Intravenous: peripheral administration – 20mL Glycophos® diluted in 500mL glucose 5% or sodium chloride 0·9%. Infuse over 12 hours. Half above dose in patients with eGFR less than 30mL/min. |
Check adjusted calcium, phosphate, sodium, magnesium and potassium every 12 hours. |
|
| Magnesium | 0.5 to 0.7mmol/L |
Oral: 5mL magnesium hydroxide mixture 3 times daily. Via enteral feeding tube: 1 to 2 magnesium glycerophosphate tablets 3 times daily. Crush tablets and dissolve in 50mL water. Half above dose in adults with eGFR less than 30mL/min. |
Check magnesium levels daily |
| Less than 0.5mmol/L |
Intravenous: peripheral administration – 10mL magnesium sulfate 50% injection in 250mL glucose 5% over 3 hours. Give 3 doses at 12 hour intervals. If eGFR less than 30mL/min – 10mmol (5mL) magnesium sulfate 50% (2mmol/mL) in 250mL glucose 5% over 6 hours. Give 3 doses at 12 hour intervals. |
Monitor BP, heart rate, respiratory rate, urine output and for signs of hypermagnesaemia during infusion. Check magnesium 6 hours after third infusion ends unless eGFR less than 30mL/min. eGFR less than 30mL/min |
|
| Adjusted calcium | 2.0 to 2.23 mmol/L |
Oral: Sandocal® 1000, 1 to 2 tablets daily. Prescribe outwith mealtimes. Via enteral feeding tube: dissolve Sandocal® 1000, 1 to 2 tablets daily in 30 to 50mL water. Consider alfacalcidol if patient has renal failure. |
Recheck adjusted calcium after 24 hours. |
| Less than 2.0mmol/L |
Intravenous: 50mL (11·25mmol) calcium gluconate 10% injection in 500mL sodium chloride 0·9% or glucose 5%. Infuse over 4 hours. |
Check adjusted calcium and magnesium 60 minutes after infusion ends. |
|
| 3·0 to 3·5mmol/L |
Oral: Sando-K® 2 tablets 3 times daily. |
Monitor potassium after 2 days treatment then twice weekly until stable. |
|
| 2·5 to 2·9mmol/L and low risk of complications |
Oral: Sando-K® 3 tablets 3 times daily. |
Monitor potassium daily until plasma K+ greater than 2·9mmol/L and then monitor as for 3·0 to 3·5mmol/L. |