see also: [[Hypomagnesemia#Mg Treatment]] > **MgSO4** > - 1g = 4mmol = ~8meq > - ==2.47 g = 10 mmol == > - 2 - 4g/day = 8-16 mmol **Side effects:** - hypotension 2/2 reduction in systemic vascular resistance - facial flushing - visual disturbance ![[Pasted image 20231120002347.png]] > request magnesium level and review if resp rate <12 > urine output <100 in 4 H > loss of patellar reflexes > further seizures ![[Pasted image 20231120004135.png| side effects from RWH magnesium guideline]] # Treat hypermagnesaemia - tx of serum level >3.5 mmol/L - calcium gluconate 10-20mL of 10% or 5mL of CaCl2 over 10 min - note, [Austin calcium gluconate guideline](x-devonthink-item://8DA126CD-D771-4A57-94B6-2DD07771A659)says 20-40mL of calcium gluconate (2-4g or 4.4-8.8 mmol) IV over 5-15 min , but the [RWH magnesium sulphate guideline](https://www.thewomens.org.au/health-professionals/clinical-resources/clinical-guidelines-gps) suggests the lower dose - +/- lasix - haemodialysis if severe renal impairment # Dose ## [[Pre-eclampsia|Eclampsia]] PPx - 4g (eg 8mL of 500mg/mL 50% solution) of MgSO4 over 15 minutes (16 mmol → likely round-up to 20) - **note** comes in in 10mmol vials which equal 2.47g, so 20 mmol = 5g - maintenance 1g/hour - therapeutic level of magnesium: 1.7 to 3.5 mmol/L ## [[Torsades de Pointes]] 1-2g ## [[Asthma]] 10mmol over 20 min ## [[pre-term labour]] - 4g or 20mmol (usually 2 vials) for neuroprotection if birth <24 hours and gestation < 20 weeks