Dosing & Uses
Dosage Forms & Strengths
injectable solution
- 40mg/mL
- 80mg/mL
- 50%
infusion solution
- 1g/100mL
- 2g/100mL
Hypomagnesemia
Mild: 1 g IM q6hr for 4 doses
Severe
- Asymptomatic: 4-8 g at ≤1 g/hr
- Symptomatic: 4-8 g at ≤4 g over 4-5 min
Toxemia of Pregnancy
Indicated to prevent seizures associated with pre-eclampsia, and for control of seizures with eclampsia
4-5 g (diluted in 250 mL NS/D5W) IV in combination with either (a) up to 10 g (20 mL of undiluted 50% solution) divided and administered IM into each buttock or (b) after initial IV dose, 1-2 g/hr IV; may administer q4hr as necessary
Torsades de Pointes
With pulse (ACLS): 1-2 g slow IV (diluted in 50-100 mL D5W) over 5-60 minutes, then 0.5-1 g/hr IV
Cardiac arrest (ACLS): 1-2 g slow IV (diluted in 10 mL D5W) over 5-20 minutes
Preterm Labor (Off-label)
Used as a tocolytic to stop preterm labor
Loading dose: 4-6 g IV over 20 minutes; maintenance: 2-4 g/hr IV for 12-24 hours as tolerated after contractions cease
Do not exceed 5-7 days of continuous treatment; longer treatment duration may lead to hypocalcemia in developing fetus resulting in neonates with skeletal abnormalities related to osteopenia
Dosing Modifications
Severe renal impairment: Do not exceed 20 g/48 hr
Dosage Forms & Strengths
injectable solution
- 40mg/mL
- 80mg/mL
- 50%
infusion solution
- 1g/100mL
- 2g/100mL
Acute Nephritis
100 mg/kg IM q4-6hr PRN or 20-40 mg/kg IM PRN
Severe: 100-200 mg/kg IV as 1-3% solution; administer total dose within 1 hr, one-half within first 15-20 minutes
Hypomagnesemia
IV/IM: 25-50 mg/kg q4-6hr for 3-4 doses PRN
PO: 100-200 mg/kg q6hr
Bronchospasm (Off-label)
25-50 mg/kg IV over 10-20 minutes
Interactions
Interaction Checker
No Results
Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor
Contraindicated (0)
Serious - Use Alternative (7)
- baloxavir marboxil
magnesium sulfate will decrease the level or effect of baloxavir marboxil by cation binding in GI tract. Avoid or Use Alternate Drug. Baloxavir may bind to polyvalent cations resulting in decreased absorption. Studies in monkeys showed concurrent use with calcium, aluminum, or iron caused significantly decreased plasma levels. Human studies not conducted.
- demeclocycline
magnesium sulfate decreases levels of demeclocycline by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug.
- doxycycline
magnesium sulfate decreases levels of doxycycline by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug.
- eltrombopag
magnesium sulfate decreases levels of eltrombopag by inhibition of GI absorption. Applies only to oral form of both agents. Contraindicated. Separate by at least 4 hours.
- minocycline
magnesium sulfate decreases levels of minocycline by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug.
- oxytetracycline
magnesium sulfate decreases levels of oxytetracycline by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug.
- tetracycline
magnesium sulfate decreases levels of tetracycline by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug.
Monitor Closely (19)
- atracurium
magnesium sulfate increases effects of atracurium by pharmacodynamic synergism. Use Caution/Monitor. Interaction occurs with parenteral magnesium.
- ciprofloxacin
magnesium sulfate decreases levels of ciprofloxacin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Coadministration of ciprofloxacin with multivalent cation-containing products may reduce the bioavailability of ciprofloxacin by 90%. Administer ciprofloxacin at least 2 hours before or 6 hours after using these products. Use alternatives if available.
- cisatracurium
magnesium sulfate increases effects of cisatracurium by pharmacodynamic synergism. Use Caution/Monitor. Interaction occurs with parenteral magnesium.
- delafloxacin
magnesium sulfate will decrease the level or effect of delafloxacin by cation binding in GI tract. Modify Therapy/Monitor Closely. Oral delafloxacin form chelates with alkaline earth and transition metal cations. Administer oral delafloxacin at least 2 hr before or 6 hr after these agents.
- dichlorphenamide
dichlorphenamide and magnesium sulfate both decrease serum potassium. Use Caution/Monitor.
- fleroxacin
magnesium sulfate decreases levels of fleroxacin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Separate by 2 hours.
- gemifloxacin
magnesium sulfate decreases levels of gemifloxacin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Separate by 2 hours.
- levofloxacin
magnesium sulfate decreases levels of levofloxacin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Separate by 2 hours.
- moxifloxacin
magnesium sulfate decreases levels of moxifloxacin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Separate by 2 hours.
- nifedipine
magnesium sulfate, nifedipine. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Hypotension, neuromuscular blockade.
- ofloxacin
magnesium sulfate decreases levels of ofloxacin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Separate by 2 hours.
- pancuronium
magnesium sulfate increases effects of pancuronium by pharmacodynamic synergism. Use Caution/Monitor. Interaction occurs with parenteral magnesium.
- penicillamine
magnesium sulfate decreases levels of penicillamine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Separate by 2 hours.
- rapacuronium
magnesium sulfate increases effects of rapacuronium by pharmacodynamic synergism. Use Caution/Monitor. Interaction occurs with parenteral magnesium.
- rilpivirine
magnesium sulfate decreases levels of rilpivirine by increasing gastric pH. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Coadministration of antacids with rilpivirine may cause significant decreases in rilpivirine plasma concentrations because of increased gastric pH. If antacids must be administered, they should given at least 2 hr before or at least 4 hr after rilpivirine.
- rocuronium
magnesium sulfate increases effects of rocuronium by pharmacodynamic synergism. Use Caution/Monitor. Interaction occurs with parenteral magnesium.
- sodium polystyrene sulfonate
sodium polystyrene sulfonate increases levels of magnesium sulfate by decreasing renal clearance. Use Caution/Monitor. Risk of seizure.
- succinylcholine
magnesium sulfate increases effects of succinylcholine by pharmacodynamic synergism. Use Caution/Monitor. Interaction occurs with parenteral magnesium.
- vecuronium
magnesium sulfate increases effects of vecuronium by pharmacodynamic synergism. Use Caution/Monitor. Interaction occurs with parenteral magnesium.
Minor (40)
- amikacin
amikacin decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- amiloride
amiloride increases levels of magnesium sulfate by decreasing renal clearance. Minor/Significance Unknown.
- amphotericin B deoxycholate
amphotericin B deoxycholate decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- bazedoxifene/conjugated estrogens
bazedoxifene/conjugated estrogens decreases levels of magnesium sulfate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- bendroflumethiazide
bendroflumethiazide decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- bumetanide
bumetanide decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- calcitonin salmon
calcitonin salmon increases levels of magnesium sulfate by decreasing renal clearance. Minor/Significance Unknown.
- chlorothiazide
chlorothiazide decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- chlorthalidone
chlorthalidone decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- conjugated estrogens
conjugated estrogens decreases levels of magnesium sulfate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- conjugated estrogens, vaginal
conjugated estrogens, vaginal decreases levels of magnesium sulfate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- cyclopenthiazide
cyclopenthiazide decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- dextrose
dextrose decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- dextrose (Antidote)
dextrose (Antidote) decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- digoxin
digoxin decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- doxercalciferol
doxercalciferol increases levels of magnesium sulfate by enhancing GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.
- drospirenone
drospirenone increases levels of magnesium sulfate by decreasing renal clearance. Minor/Significance Unknown.
- estradiol
estradiol decreases levels of magnesium sulfate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- estrogens conjugated synthetic
estrogens conjugated synthetic decreases levels of magnesium sulfate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- estrogens esterified
estrogens esterified decreases levels of magnesium sulfate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- estropipate
estropipate decreases levels of magnesium sulfate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- ethacrynic acid
ethacrynic acid decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- furosemide
furosemide decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- gentamicin
gentamicin decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- glucagon intranasal
glucagon intranasal increases levels of magnesium sulfate by decreasing renal clearance. Minor/Significance Unknown.
- hydrochlorothiazide
hydrochlorothiazide decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- ibandronate
magnesium sulfate decreases levels of ibandronate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.
- indapamide
indapamide decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- mannitol
mannitol decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- mestranol
mestranol decreases levels of magnesium sulfate by Other (see comment). Minor/Significance Unknown. Comment: Magnesium shifted from blood to tissue storage.
- methyclothiazide
methyclothiazide decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- metolazone
metolazone decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- neomycin PO
neomycin PO decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- nitrofurantoin
magnesium sulfate decreases levels of nitrofurantoin by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.
- paromomycin
paromomycin decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- spironolactone
spironolactone increases levels of magnesium sulfate by decreasing renal clearance. Minor/Significance Unknown.
- streptomycin
streptomycin decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- tobramycin
tobramycin decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- torsemide
torsemide decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.
- triamterene
triamterene increases levels of magnesium sulfate by decreasing renal clearance. Minor/Significance Unknown.
Adverse Effects
Frequency Not Defined
Circulatory collapse
Respiratory paralysis
Hypothermia
Pulmonary edema
Depressed reflexes
Hypotension
Flushing
Drowsiness
Depressed cardiac function
Diaphoresis
Hypocalcemia
Hypophosphatemia
Hyperkalemia
Visual changes
Warnings
Contraindications
Hypersensitivity
Myocardial damage, diabetic coma, heart block
Hypermagnesemia
Hypercalcemia
Administration during 2 hours preceding delivery for mothers with toxemia of pregnancy
Cautions
Fetal skeletal demineralization, hypocalcemia, and hypermagnesemia abnormalities reported with continuous long-term use (ie, longer than 5-7 days) for off-label treatment of preterm labor in pregnant women; the effect on the developing fetus may result in neonates with skeletal abnormalities
In patients with renal impairment, ensure that renal excretory capacity is not exceeded
Use with caution in digitalized patients
Use with extreme caution in patients with myasthenia gravis or other neuromuscular disease
Hypomagnesemia is usually associated with hypokalemia (potassium levels must be normalized)
Monitor renal function, blood pressure, respiratory rate, and deep tendon reflex when magnesium sulfate is administered parenterally
Pregnancy & Lactation
Pregnancy category: D
Fetal skeletal demineralization, hypocalcemia, and hypermagnesemia reported with continuous long-term use (ie, longer than 5-7 days) for off-label treatment of preterm labor in pregnant women; the effect on the developing fetus may result in neonates with skeletal abnormalities
Continuous administration of magnesium sulfate injection to treat preterm labor is not approved and that the safety and efficacy of use for this indication are not established
Lactation: Safe
Pregnancy Categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available.Pharmacology
Mechanism of Action
Depresses CNS, blocks peripheral neuromuscular transmission, produces anticonvulsant effects; decreases amount of acetylcholine released at end-plate by motor nerve impulse
Slows rate of SA node impulse formation in myocardium and prolongs conduction time
Promotes movement of calcium, potassium, and sodium in and out of cells and stabilizes excitable membranes
Promotes osmotic retention of fluid in colon, causing distention and increased peristaltic activity, which subsequently results in bowel evacuation
Absorption
Onset (anticonvulsant): IV, immediate; IM, 1 hr
Duration (anticonvulsant): IV, 30 min; IM, 3-4 hr
Distribution
Protein bound: 30%
Extracellular distribution: 1-2%
Elimination
Excretion: Urine
Administration
IV Incompatibilities
Solution: IV fat emulsion 10%
Additive: Amphotericin B, cyclosporine, dobutamine, polymyxin B sulfate, procaine, sodium bicarbonate
Y-site: Alatrofloxacin, amiodarone (at 500 mg/mL MgSO4; may be compatible at 20 mg/mL), amphotericin B cholesteryl sulfate, cefepime, ciprofloxacin (?)
IV Preparation
Intermittent infusion: Dilute to 60 mg/mL
IV Administration
Infuse over 2-4 hr (hypomagnesemia) or as otherwise specified; rate not to exceed 125 mg/kg/hr
In severe cases, half of the dose may be infused over first 15-20 minutes
Rapid infusions (over 10-20 minutes) may be used for treatment of severe asthma or torsades de pointes ventricular tachycardia
Cautiously infuse diluted solution through patent IV line
IM Administration
Dilute to maximum concentration of 200 mg/mL before injection
Images
| BRAND | FORM. | UNIT PRICE | PILL IMAGE |
|---|---|---|---|
| magnesium sulfate injection - | 500 mg/mL (50 %) vial |  | |
| magnesium sulfate injection - | 500 mg/mL (50 %) vial |  | |
| magnesium sulfate injection - | 500 mg/mL (50 %) vial |  | |
| magnesium sulfate injection - | 500 mg/mL (50 %) vial |  | |
| magnesium sulfate injection - | 500 mg/mL (50 %) vial |  | |
| magnesium sulfate injection - | 500 mg/mL (50 %) vial |  | |
| magnesium sulfate injection - | 500 mg/mL (50 %) vial |  | |
| magnesium sulfate injection - | 500 mg/mL (50 %) solution |  | |
| magnesium sulfate injection - | 500 mg/mL (50 %) vial |  | |
| magnesium sulfate injection - | 500 mg/mL (50 %) vial |  |
Copyright © 2010 First DataBank, Inc.
Patient Handout
magnesium sulfate oral
MAGNESIUM SUPPLEMENT - ORAL
(mag-NEE-zee-um)
COMMON BRAND NAME(S): Uro-Mag
USES: This medication is a mineral supplement used to prevent and treat low amounts of magnesium in the blood. Some brands are also used to treat symptoms of too much stomach acid such as stomach upset, heartburn, and acid indigestion. Magnesium is very important for the normal functioning of cells, nerves, muscles, bones, and the heart. Usually, a well-balanced diet provides normal blood levels of magnesium. However, certain situations cause your body to lose magnesium faster than you can replace it from your diet. These situations include treatment with "water pills" (diuretics such as furosemide, hydrochlorothiazide), a poor diet, alcoholism, or other medical conditions (such as severe diarrhea/vomiting, stomach/intestinal absorption problems, poorly controlled diabetes).
HOW TO USE: Take this product by mouth as directed. Follow all directions on the product package. If you have any questions, ask your doctor or pharmacist.It is best to take magnesium supplements with a meal to reduce stomach upset and diarrhea unless otherwise directed by the product instructions or your doctor.Take each dose with a full glass (8 ounces or 240 milliliters) of water unless your doctor directs you otherwise. Swallow extended-release capsules and delayed-release/enteric coated tablets or capsules whole. Do not crush or chew extended-release or delayed-release/enteric coated capsules or tablets. Doing so can release all of the drug at once, increasing the risk of side effects. Also, do not split extended-release tablets unless they have a score line and your doctor or pharmacist tells you to do so. Swallow the whole or split tablet without crushing or chewing.If you are taking the chewable tablets, chew each tablet thoroughly before swallowing.If you are using a liquid product, use a medication measuring device to carefully measure the dose. Do not use a household spoon because you may not get the correct dose. If you are using a suspension, shake the bottle well before each dose.Take this medication regularly in order to get the most benefit from it. Remember to take it at the same time(s) each day. Dosage is based on your medical condition and response to treatment. Do not increase your dose or take it more often than directed on the product package or by your doctor. Too much magnesium in the blood can cause serious side effects.Tell your doctor if symptoms of low magnesium blood levels (such as muscle cramps, tiredness, irritability, depression) last or get worse. If you think you may have a serious medical problem, get medical help right away.
SIDE EFFECTS: Stomach upset and diarrhea may occur. Taking this product with a meal helps to reduce these effects. If either of these effects last or get worse, tell your doctor or pharmacist promptly.If your doctor has directed you to use this medication, remember that your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
PRECAUTIONS: Before taking a magnesium supplement, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.If you have the following health problem, consult your doctor or pharmacist before using this product: kidney disease.Liquids, powders, or some other forms of this product may contain sugar and/or aspartame. Liquid products may also contain alcohol. Caution is advised if you have diabetes, alcohol dependence, liver disease, phenylketonuria (PKU), or any other condition that requires you to limit/avoid these substances in your diet. Ask your doctor or pharmacist about using this product safely.During pregnancy, this product should be used only when clearly needed. Discuss the risks and benefits with your doctor.It is unknown if this product passes into breast milk. Consult your doctor before breastfeeding.
DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.Some products that may interact with this drug are: cellulose sodium phosphate, digoxin, sodium polystyrene sulfonate.Magnesium can bind with certain medications, preventing their full absorption. If you are taking a tetracycline-type medication (such as demeclocycline, doxycycline, minocycline, tetracycline), separate the time of the dose from the time of the magnesium supplement dose by at least 2 to 3 hours. If you are taking a bisphosphonate (for example, alendronate), a thyroid medication (for example, levothyroxine), or a quinolone-type antibiotic (such as ciprofloxacin, levofloxacin), ask your doctor or pharmacist about how long you should wait between doses and for help finding a dosing schedule that will work with all your medications.Check the labels on all your prescription and nonprescription/herbal products (such as antacids, laxatives, vitamins) because they may contain magnesium. Ask your pharmacist about using those products safely.
OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include slow heartbeat, severe drowsiness, dizziness, confusion, muscle weakness, loss of consciousness.
NOTES: Lab and/or medical tests (such as magnesium blood levels, kidney function) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.Magnesium supplements are available in different forms with different amounts of magnesium. Many are available without a prescription. Ask your doctor or pharmacist for help in selecting the best product for you.Eat a well-balanced diet. Foods high in magnesium include avocados, bananas, beans, whole grain cereals, green vegetables, and nuts.
MISSED DOSE: If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.
STORAGE: Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised March 2024. Copyright(c) 2024 First Databank, Inc.
IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.
Formulary
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