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magnesium sulfate
generic
Adult Dosing .
Dosage forms: INJ
Special Note
- [strength clarification]
- Info: MgSO4 contains approximately 9.86% elemental Mg; 1 g MgSO4 = 98.6 mg (8.12 mEq) elemental Mg; doses expressed as MgSO4
hypomagnesemia, symptomatic
- [hemodynamically stable]
- Dose: 4-8 g IV over 12-24h prn; Start: 1-2 g IV over 5-60min x1; Info: adjust dose based on serum magnesium levels
- [hemodynamically unstable]
- Dose: 1-2 g IV over 2-15min x1; Info: may follow with 3-20 mg/min IV
hypomagnesemia, asymptomatic
- [plasma Mg <1 mg/dL]
- Dose: 4-8 g IV over 12-24h; Alt: up to 250 mg/kg/dose IM within 4h; Info: adjust dose based on serum magnesium levels
- [plasma Mg 1-1.5 mg/dL]
- Dose: 2-4 g IV over 4-12h; Info: adjust dose based on serum magnesium levels
- [plasma Mg 1.6-1.9 mg/dL]
- Dose: 1-2 g IV over 1-2h; Alt: 1 g IM q6h x4 doses; Info: adjust dose based on serum magnesium levels
seizures, preeclampsia or eclampsia-associated
- [1-2 g/h IV for at least 24h]
- Start: 4-6 g IV x1; Max: 40 g/24h; x5-7 days; Alt: if no IV access, give 5 g IM x1 to each buttock, then 5 g IM to alternate buttocks q4h prn
tocolysis (off-label)
- [2-4 g/h IV x12-24h]
- Start: 4-6 g IV x1; Max: x5-7 days
ventricular arrhythmia (off-label)
- [3-20 mg/min IV x5-48h]
- Start: 2-6 g IV x1
torsades de pointes (off-label)
- [without cardiac arrest]
- Dose: 1-2 g IV over 15min x1; Info: may follow with 3-20 mg/min IV
- [with cardiac arrest]
- Dose: 1-2 g IV over 1-2min x1; Info: may follow with 3-20 mg/min IV
severe asthma exacerbation, adjunct tx (off-label)
- [2 g IV x1]
renal dosing
- [seizures, preeclampsia or eclampsia-associated]
- severe impairment: max 20 g/48h
- HD/PD: not defined
- [all other indications]
- severe impairment: decr. usual dose, amount not defined
- HD/PD: not defined
hepatic dosing
- [not defined]
Peds Dosing .
- Dosage forms: INJ
Special Note
- [strength clarification]
- Info: MgSO4 contains approximately 9.86% elemental Mg; 1 g MgSO4 = 98.6 mg (8.12 mEq) elemental Mg; doses expressed as MgSO4
hypomagnesemia, symptomatic (off-label)
- [neonates]
- Dose: 25-50 mg/kg/dose IV q8-12h x2-3 doses; Max: 2 g/dose; Info: adjust dose based on serum magnesium levels
- [infants/children]
- Dose: 25-50 mg/kg/dose IV q6h x3-4 doses; Max: 2 g/dose; Info: adjust dose based on serum magnesium levels
ventricular arrhythmias, post-cardiopulmonary bypass (off-label)
- [25-50 mg/kg/dose IV x1]
- Max: 2 g/dose; Info: for prevention and tx
torsades de pointes (off-label)
- [25-50 mg/kg/dose IV/IO x1 prn]
- Max: 2 g/dose
severe asthma exacerbation, adjunct tx (off-label)
- [2-5 yo]
- Dose: 40-50 mg/kg/dose IV x1; Max: 2g/dose
- [>5 yo]
- Dose: 40-50 mg/kg/dose IV x1; Max: 2g/dose
renal dosing
- [not defined]
- renal impairment: consider adult renal dosing for guidance
- HD/PD: not defined
hepatic dosing
- [not defined]
Contraindications / Cautions .
- hypersensitivity to drug or ingredient
- myocardial damage
- diabetic coma
- heart block
- caution: renal impairment
- caution: botulism
Drug Interactions .
Overview
magnesium sulfate
magnesium salt (supplement)
- hypotensive effects
- neuromuscular blocking effects
Avoid/Use Alternative
- aldesleukin
- calcitriol
- doxercalciferol
- lofexidine
Monitor/Modify Tx
- acebutolol
- alfentanil
- alfuzosin
- aliskiren
- alprostadil intracavernous
- amantadine
- amifostine
- amitriptyline
- amlodipine
- amoxapine
- apomorphine
- apraclonidine ophthalmic
- aprocitentan
- aripiprazole bimonthly injection
- aripiprazole lauroxil
- aripiprazole monthly injection
- aripiprazole oral
- articaine
- asenapine
- atenolol
- atracurium
- avanafil
- azilsartan medoxomil
- benazepril
- berberine
- betaxolol
- betaxolol ophthalmic
- bethanechol
- bexagliflozin
- bisoprolol
- bortezomib
- brexpiprazole
- brexucabtagene autoleucel
- brimonidine ophthalmic
- brimonidine topical
- bumetanide
- bupivacaine
- bupivacaine liposomal
- buprenorphine
- cabergoline
- canagliflozin
- cannabis
- cariprazine
- carteolol ophthalmic
- carvedilol
- chloroprocaine
- chlorothiazide
- chlorthalidone
- cilostazol
- cisatracurium
- clevidipine
- clonidine
- clozapine
- codeine
- coenzyme Q-10
- dapagliflozin
- denileukin diftitox
- desipramine
- dexmedetomidine
- dexmedetomidine injection
- dihydrocodeine
- diltiazem
- dinutuximab
- dipyridamole
- doxazosin
- doxepin
- dronabinol
- duloxetine
- empagliflozin
- entacapone
- eplerenone
- epoprostenol
- ertugliflozin
- esmolol
- ethanol (alcoholic beverage)
- ethanol injection
- etripamil nasal
- felodipine
- fentanyl
- ferumoxytol
- flaxseed
- fluphenazine
- fosinopril
- foslevodopa
- furosemide
- garlic
- gilteritinib
- guanfacine
- haloperidol
- hydralazine
- hydrochlorothiazide
- hydromorphone
- iloperidone
- iloprost
- indapamide
- irbesartan
- iron sucrose
- isocarboxazid
- labetalol
- landiolol
- levobunolol ophthalmic
- levodopa
- levorphanol
- lidocaine
- lisinopril
- losartan
- lubiprostone
- lumateperone
- lurasidone
- maraviroc
- mepivacaine
- methadone
- methyldopa
- methylene blue injection
- metoprolol
- midazolam
- milrinone
- milsaperidone
- minoxidil
- mirtazapine
- molindone
- morphine
- nadolol
- nattokinase
- naxitamab
- nebivolol
- nicardipine
- nifedipine
- nisoldipine
- nitric oxide
- nitrite
- nitroglycerin
- nitroprusside
- nortriptyline
- obinutuzumab
- olanzapine
- oliceridine
- opicapone
- oxazepam
- oxycodone
- oxymorphone
- paliperidone
- palopegteriparatide
- pentamidine
- pentobarbital
- phenelzine
- phenobarbital
- pindolol
- pramipexole
- prazosin
- procarbazine
- prochlorperazine
- promethazine
- propafenone
- propofol
- propranolol
- quetiapine
- quinapril
- ramipril
- rasagiline
- remimazolam
- riociguat
- risperidone
- ropinirole
- ropivacaine
- sacubitril
- safinamide
- selegiline
- selegiline transdermal
- sevoflurane
- sildenafil
- silodosin
- sodium ferric gluconate complex
- sotagliflozin
- sotalol
- sparsentan
- spironolactone
- tadalafil
- tamsulosin
- taurine
- telmisartan
- terazosin
- thalidomide
- thioridazine
- thiothixene
- timolol
- timolol ophthalmic
- tizanidine
- tolcapone
- tramadol
- tranylcypromine
- trazodone
- treprostinil
- valsartan
- vardenafil
- verapamil
- vosoritide
- yohimbe
- ziprasidone
Caution Advised
- pyridostigmine
- rocuronium
- vecuronium
Adverse Reactions .
Serious Reactions
- cardiovascular collapse
- respiratory paralysis
- hypothermia
- depressed cardiac function
- pulmonary edema
Common Reactions
- depressed reflexes
- hypotension
- flushing
- drowsiness
- impaired cardiac function
- diaphoresis
- hypocalcemia
- hypophosphatemia
- hyperkalemia
- vision changes
Safety/Monitoring .
Monitoring Parameters
Cr at baseline; Mg; urine output if renal impairment; patellar reflexes prior to repeat doses
Aluminum Content
toxic levels with prolonged tx if renal impairment, especially premature neonates; CNS, bone toxicities may occur
Look/Sound-Alike Drug Names
magnesium sulfate confused with: magnesium citrate; morphine sulfate
Pregnancy/Lactation .
Pregnancy
Clinical Summary
may use during pregnancy, though weigh risk/benefit with prolonged use; risk of fetal harm not expected, though risk of fetal hypocalcemia and congenital rickets with prolonged use based on limited human data
Lactation
Clinical Summary
may use while breastfeeding; no known risk of infant harm based on limited human data; possible risk of delayed milk production with use >6h based on limited human data
Pharmacology .
Metabolism: for magnesium sulfate: none; CYP450: none; Info: 20% systemic absorption
Excretion: for magnesium sulfate: urine; Half-life: unknown
Subclass: Advanced Life Support (ACLS/PALS/NALS) ; Antiarrhythmics, Parenteral ; Labor Suppression/Tocolytics ; Minerals
Mechanism of Action
for magnesium sulfate: participates in physiologic processes
Formulary .
No Formulary Selected
Manufacturer/Pricing .
Manufacturer: generic
DEA/FDA: Rx
Retail Price
Estimated prices only. For current pricing, visit GoodRx.
injectable solution:
- 10 g/20 mL (3 vial, 20 mL): $12.00
injectable solution:
- 5 g/10 mL (1 carton, ten 10 mL syringes): $32.00
injectable solution:
- 1 g/2 mL (25 vial, 2 mL): $17.00
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