Anticoagulation, endocrine and GI
Magnesium sulfate (MgSO4) drip
Mag, MgSO4
Dosing
| Start | Severe preeclampsia or eclampsia: 4–6 g over 15–20 minutes, then 1–2 g/h |
|---|---|
| Titrate | By reflexes, breathing, urine output and levels |
| Maximum | 2 g/h (more only with levels and close monitoring) |
| Common bags | 20 g in 500 mL (40 mg/mL); 40 g in 1,000 mL (40 mg/mL) |
| Dose units | g/h |
Line and administration
- Dedicated pump channel; high-alert drug with an independent double-check
Watch for
- Loss of deep tendon reflexes first, then respiratory depression (stop if RR under 12)
- Kidney failure raises levels: watch urine output
- Antidote: calcium gluconate 1 g IV
- Can precipitate weakness or crisis in myasthenia gravis: avoid unless essential
Magnesium sulfate: full drug monographIndications, mechanism, pharmacokinetics, cautions and every dose the app lists.
In the one-pagers
- Obstetric EmergenciesPreeclampsia and eclampsia: Eclampsia: new seizures with no other cause. Call for help, protect from injury, side-lying, prevent aspiration, oxygen. Most stop on their own; magnesium prevents the next.
- ACLS Algorithms in BriefCPR quality, shocks and drugs: Not routine in arrest: calcium, bicarbonate, magnesium, vasopressin, high-dose epinephrine, pacing. Hyperkalemic arrest: calcium and bicarbonate may be considered (2025: benefit unproven).
- Myasthenic Crisis and Guillain-Barré SyndromeMyasthenic crisis: Worsen MG: fluoroquinolones (boxed warning), aminoglycosides, macrolides, IV magnesium, β-blockers, procainamide, neuromuscular blockers, volatile anesthetics, checkpoint inhibitors
- Asthma and COPD ExacerbationsSevere asthma: IV magnesium 2 g over 20 min for severe attacks
- Rhythm GalleryVentricular: Torsades: polymorphic VT twisting around the baseline, usually with a long QT. Pulseless: defibrillate. With a pulse: magnesium 1–2 g IV over about 15 min; avoid QT-prolonging drugs such as amiodarone.
- Subarachnoid HemorrhageNimodipine and delayed cerebral ischemia: No benefit: Prophylactic triple-H (harmful), statins, IV magnesium, clazosentan
Practice Obstetric Emergencies questions free26 exam-style questions with rationales on the topic where magnesium sulfate comes up most. No account or download needed.
Other anticoagulation, endocrine and gi
- Heparin
- Insulin (regular)
- Amiodarone
- Diltiazem
- Octreotide
- Pantoprazole
- Furosemide
- Argatroban
- Bivalirudin
- Procainamide
- Lidocaine
- Naloxone
- Eptifibatide
- Bumetanide
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For education and exam preparation only. Follow your institution’s protocols. Study aid: check every dose against the order, the bag label, your pump library and your institution's protocol.