Magn Sulf/d5w 10mg/ml Inj, 100ml
It is used to treat or prevent low magnesium levels.It is used to prevent and control seizures during pregnancy.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Electrolyte, Anticonvulsant, Tocolytic, Antiarrhythmic
Pharmacologic Class
Mineral/Electrolyte Replacement, CNS Depressant, Smooth Muscle Relaxant
Pregnancy Category
Category D
FDA Approved
Jan 1970
DEA Schedule
Not Controlled
Overview
What is this medicine?
Magnesium sulfate is a mineral given by injection, often into a vein. It's used for several conditions, including preventing seizures in pregnant women with severe high blood pressure (pre-eclampsia/eclampsia), treating low magnesium levels in the body, and sometimes for severe asthma attacks. It works by relaxing muscles and calming the nervous system.
How to Use This Medicine
Taking Your Medication Correctly
To ensure safe and effective use, take this medication exactly as directed by your doctor. Carefully read all the information provided to you and follow the instructions closely. This medication can be administered in two ways: as an injection into a muscle or as an infusion into a vein, which is given over a period of time.
Storing and Disposing of Your Medication
If you need to store this medication at home, consult with your doctor, nurse, or pharmacist to determine the proper storage method.
Missing a Dose
If you miss a dose, contact your doctor immediately to find out what steps to take next.
To ensure safe and effective use, take this medication exactly as directed by your doctor. Carefully read all the information provided to you and follow the instructions closely. This medication can be administered in two ways: as an injection into a muscle or as an infusion into a vein, which is given over a period of time.
Storing and Disposing of Your Medication
If you need to store this medication at home, consult with your doctor, nurse, or pharmacist to determine the proper storage method.
Missing a Dose
If you miss a dose, contact your doctor immediately to find out what steps to take next.
Lifestyle & Tips
- Report any unusual symptoms immediately to your healthcare provider.
- Maintain adequate hydration as advised by your doctor.
- Avoid alcohol and other sedatives while receiving magnesium sulfate, as they can increase drowsiness and breathing problems.
Available Forms & Alternatives
Available Strengths:
Dosing & Administration
Adult Dosing
Standard Dose:
Highly variable based on indication. For eclampsia/pre-eclampsia: 4-6 g IV loading dose over 15-20 min, followed by 1-2 g/hour continuous IV infusion. For hypomagnesemia: 1-4 g IV over 1-4 hours, repeated as needed based on serum levels.
Dose Range:
1 - 6 mg
Condition-Specific Dosing:
Eclampsia/Pre-eclampsia:
Loading: 4-6 g IV over 15-20 min; Maintenance: 1-2 g/hour IV infusion. Continue for 24 hours postpartum or after last seizure.
Hypomagnesemia (mild to moderate):
1-2 g IV over 1 hour.
Hypomagnesemia (severe/symptomatic):
2-4 g IV over 1-4 hours, then 1-2 g/hour IV infusion.
Asthma Exacerbation (severe):
2 g IV over 20 minutes.
Pediatric Dosing
Neonatal:
Not established for routine use; specific indications (e.g., persistent pulmonary hypertension, severe hypomagnesemia) may warrant use under strict monitoring. Dosing typically 25-50 mg/kg/dose IV.
Infant:
Not established for routine use; specific indications (e.g., severe hypomagnesemia) may warrant use under strict monitoring. Dosing typically 25-50 mg/kg/dose IV.
Child:
Hypomagnesemia: 25-50 mg/kg/dose IV (max 2 g) over 2-4 hours, repeated as needed. Asthma Exacerbation (severe): 25-50 mg/kg IV (max 2 g) over 15-30 minutes.
Adolescent:
Hypomagnesemia: 25-50 mg/kg/dose IV (max 2 g) over 2-4 hours, repeated as needed. Asthma Exacerbation (severe): 25-50 mg/kg IV (max 2 g) over 15-30 minutes. For eclampsia/pre-eclampsia, adult dosing may apply.
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment, but monitor closely.
Moderate:
Reduce dose by 25-50% or extend dosing interval. Monitor serum magnesium levels, deep tendon reflexes, and respiratory rate closely.
Severe:
Contraindicated or significantly reduced dose (e.g., 50-75% reduction) with extreme caution and continuous monitoring of serum magnesium, reflexes, and respiratory function. Risk of toxicity is high.
Dialysis:
Contraindicated or used with extreme caution at significantly reduced doses, as magnesium is cleared by dialysis. Monitor serum magnesium levels frequently.
Hepatic Impairment:
Mild:
No adjustment needed.
Moderate:
No adjustment needed.
Severe:
No adjustment needed.
Pharmacology
Mechanism of Action
Magnesium is an essential cofactor for numerous enzymatic reactions, including those involved in energy production, nucleic acid synthesis, and protein synthesis. It plays a crucial role in neuromuscular transmission, muscle contraction, and cardiac excitability. As an anticonvulsant, it depresses the central nervous system by blocking neuromuscular transmission and decreasing the amount of acetylcholine released at the motor end plate. It also acts as a peripheral vasodilator, which contributes to its hypotensive effect and may reduce cerebral edema in eclampsia. In smooth muscle, it causes relaxation, which is the basis for its tocolytic and bronchodilator effects.
Pharmacokinetics
Absorption:
Bioavailability:
100% (IV)
Tmax:
Immediate (IV)
FoodEffect:
Not applicable (IV)
Distribution:
Vd:
0.2-0.3 L/kg (distributes into bone, muscle, and soft tissues)
ProteinBinding:
Approximately 30% (to albumin)
CnssPenetration:
Limited (crosses blood-brain barrier slowly, but therapeutic levels can affect CNS)
Elimination:
HalfLife:
Approximately 4 hours (in patients with normal renal function); significantly prolonged in renal impairment.
Clearance:
Primarily renal
ExcretionRoute:
Renal (glomerular filtration)
Unchanged:
Nearly 100%
Pharmacodynamics
OnsetOfAction:
Immediate (IV)
PeakEffect:
Minutes (IV)
DurationOfAction:
Approximately 30 minutes (IV bolus); sustained with continuous infusion.
Safety & Warnings
BLACK BOX WARNING
Prolonged administration of magnesium sulfate to pregnant women (longer than 5-7 days) can result in fetal bone abnormalities (osteopenia and fractures). Neonatal hypocalcemia and hypermagnesemia have also been reported. Magnesium sulfate should be used with caution and only when clearly needed in pregnant women for prolonged periods.
Side Effects
Urgent Side Effects: Seek Medical Attention Immediately
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical help right away:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of high magnesium levels, including:
+ Confusion
+ Feeling sluggish
+ Slow movements
+ Shortness of breath
+ Upset stomach
+ Severe dizziness or passing out
Signs of low calcium levels, such as:
+ Muscle cramps or spasms
+ Numbness and tingling
+ Seizures
Other severe side effects, including:
+ Slow heartbeat
+ Flushing
+ Inability to move
+ Changes in eyesight
+ Feeling cold
+ Excessive sweating
If you experience any of the following symptoms, call your doctor right away, as they could be signs of a life-threatening muscle problem:
New or worsening muscle weakness
Trouble chewing or swallowing
Trouble breathing
Droopy eyelids
* Changes in eyesight, such as blurred vision or double vision
Other Possible Side Effects
Like all medications, this drug may cause side effects. However, many people do not experience any side effects or only have mild ones. If you have any side effects that bother you or do not go away, contact your doctor or seek medical help.
Not all possible side effects are listed here. If you have questions about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical help right away:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of high magnesium levels, including:
+ Confusion
+ Feeling sluggish
+ Slow movements
+ Shortness of breath
+ Upset stomach
+ Severe dizziness or passing out
Signs of low calcium levels, such as:
+ Muscle cramps or spasms
+ Numbness and tingling
+ Seizures
Other severe side effects, including:
+ Slow heartbeat
+ Flushing
+ Inability to move
+ Changes in eyesight
+ Feeling cold
+ Excessive sweating
If you experience any of the following symptoms, call your doctor right away, as they could be signs of a life-threatening muscle problem:
New or worsening muscle weakness
Trouble chewing or swallowing
Trouble breathing
Droopy eyelids
* Changes in eyesight, such as blurred vision or double vision
Other Possible Side Effects
Like all medications, this drug may cause side effects. However, many people do not experience any side effects or only have mild ones. If you have any side effects that bother you or do not go away, contact your doctor or seek medical help.
Not all possible side effects are listed here. If you have questions about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Feeling very sleepy or confused
- Difficulty breathing or slow breathing
- Muscle weakness or feeling floppy
- Flushing or feeling warm
- Dizziness or lightheadedness
- Blurred vision
- No urine output
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you have a heart block or any pre-existing heart problems.
If you are currently taking nifedipine or terbutaline, as these medications may interact with this drug.
Please note that this is not an exhaustive list of all potential interactions. To ensure your safety, it is crucial to disclose all of your medications, including:
Prescription and over-the-counter (OTC) drugs
Natural products
Vitamins
Additionally, inform your doctor about any health problems you have. This information will help your doctor determine whether it is safe for you to take this medication with your existing health conditions and medications. Always consult with your doctor before starting, stopping, or changing the dose of any medication to avoid potential interactions or adverse effects.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you have a heart block or any pre-existing heart problems.
If you are currently taking nifedipine or terbutaline, as these medications may interact with this drug.
Please note that this is not an exhaustive list of all potential interactions. To ensure your safety, it is crucial to disclose all of your medications, including:
Prescription and over-the-counter (OTC) drugs
Natural products
Vitamins
Additionally, inform your doctor about any health problems you have. This information will help your doctor determine whether it is safe for you to take this medication with your existing health conditions and medications. Always consult with your doctor before starting, stopping, or changing the dose of any medication to avoid potential interactions or adverse effects.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. If you are following a low-magnesium diet, consult with your doctor to discuss any potential interactions.
Regular blood tests will be necessary, as directed by your doctor, to monitor your condition. Be sure to follow your doctor's instructions for scheduling these tests and discussing the results.
This medication may contain aluminum, which can increase the risk of aluminum toxicity with long-term use. This risk is particularly higher if you have kidney problems or if you are a premature infant. It is crucial to discuss this potential risk with your doctor.
Do not take this medication if you have myasthenia gravis, as it can cause severe and potentially life-threatening breathing problems in people with this condition.
If you are pregnant or become pregnant while taking this medication, immediately contact your doctor, as it may harm the unborn baby.
If you are breastfeeding, inform your doctor, as you will need to discuss the potential risks to your baby and determine the best course of action.
Regular blood tests will be necessary, as directed by your doctor, to monitor your condition. Be sure to follow your doctor's instructions for scheduling these tests and discussing the results.
This medication may contain aluminum, which can increase the risk of aluminum toxicity with long-term use. This risk is particularly higher if you have kidney problems or if you are a premature infant. It is crucial to discuss this potential risk with your doctor.
Do not take this medication if you have myasthenia gravis, as it can cause severe and potentially life-threatening breathing problems in people with this condition.
If you are pregnant or become pregnant while taking this medication, immediately contact your doctor, as it may harm the unborn baby.
If you are breastfeeding, inform your doctor, as you will need to discuss the potential risks to your baby and determine the best course of action.
Overdose Information
Overdose Symptoms:
- Profound hypotension
- Nausea
- Vomiting
- Flushing
- Thirst
- Sedation
- Confusion
- Muscle weakness
- Loss of deep tendon reflexes
- Respiratory depression
- Bradycardia
- Cardiac arrest
What to Do:
Immediately discontinue magnesium sulfate. Administer intravenous calcium gluconate (10 mL of 10% solution) slowly to counteract magnesium toxicity. Provide respiratory support (e.g., mechanical ventilation) if needed. Ensure adequate urine output. Dialysis may be considered in severe cases with renal failure. Call 1-800-222-1222 (Poison Control) for further guidance.
Drug Interactions
Contraindicated Interactions
- Calcium channel blockers (e.g., Nifedipine, Verapamil, Diltiazem) - concurrent use with high doses of magnesium sulfate may lead to profound hypotension and neuromuscular blockade.
- Neuromuscular blockers (e.g., Succinylcholine, Vecuronium, Rocuronium) - magnesium potentiates their effects, leading to prolonged paralysis and respiratory depression.
Major Interactions
- CNS depressants (e.g., Opioids, Benzodiazepines, Barbiturates, General anesthetics) - additive CNS depression, increased risk of respiratory depression and sedation.
- Digoxin - high magnesium levels can interfere with digoxin's cardiac effects and potentially lead to heart block.
- Potassium-sparing diuretics (e.g., Spironolactone, Amiloride) - may increase serum magnesium levels, especially in renal impairment.
Moderate Interactions
- Aminoglycosides (e.g., Gentamicin, Tobramycin) - may enhance neuromuscular blockade.
- Tetracyclines (e.g., Doxycycline) - magnesium can chelate tetracyclines, reducing their absorption if given orally (less relevant for IV magnesium but good to note for other forms).
- Bisphosphonates (e.g., Alendronate) - magnesium may interfere with absorption if given orally.
Minor Interactions
- Not available
Monitoring
Baseline Monitoring
Serum Magnesium Level
Rationale: To establish baseline and guide initial dosing, especially in hypomagnesemia or renal impairment.
Timing: Prior to initiation of therapy.
Renal Function (BUN, Creatinine)
Rationale: Magnesium is primarily renally excreted; impaired renal function increases risk of toxicity.
Timing: Prior to initiation of therapy.
Deep Tendon Reflexes (DTRs)
Rationale: Magnesium toxicity manifests as diminished or absent DTRs.
Timing: Prior to initiation of therapy.
Respiratory Rate
Rationale: High magnesium levels can cause respiratory depression.
Timing: Prior to initiation of therapy.
Blood Pressure
Rationale: Magnesium can cause hypotension.
Timing: Prior to initiation of therapy.
Urine Output
Rationale: Adequate urine output is essential for magnesium excretion.
Timing: Prior to initiation of therapy.
Routine Monitoring
Serum Magnesium Level
Frequency: Every 4-6 hours during continuous infusion, or as clinically indicated.
Target: 4-7 mg/dL (for eclampsia/pre-eclampsia); 1.5-2.5 mg/dL (for hypomagnesemia correction)
Action Threshold: >7 mg/dL (toxicity risk); <4 mg/dL (subtherapeutic for eclampsia)
Deep Tendon Reflexes (DTRs)
Frequency: Hourly during continuous infusion, or every 2-4 hours.
Target: Present (2+)
Action Threshold: Diminished (1+) or Absent (0)
Respiratory Rate
Frequency: Hourly during continuous infusion, or every 2-4 hours.
Target: >12 breaths/min
Action Threshold: <12 breaths/min
Blood Pressure
Frequency: Hourly during continuous infusion, or every 2-4 hours.
Target: Within therapeutic range for indication
Action Threshold: Significant hypotension
Urine Output
Frequency: Hourly or every 2-4 hours.
Target: >25-30 mL/hour or >100 mL/4 hours
Action Threshold: <25-30 mL/hour or oliguria
Cardiac Monitoring (ECG)
Frequency: Continuous or frequent, especially with high doses or renal impairment.
Target: Normal sinus rhythm, no prolonged PR/QT intervals
Action Threshold: Bradycardia, heart block, prolonged PR/QT, widened QRS
Symptom Monitoring
- Flushing
- Sweating
- Hypotension
- Sedation
- Muscle weakness
- Absent deep tendon reflexes
- Respiratory depression
- Bradycardia
- Cardiac arrest
- Nausea
- Vomiting
- Blurred vision
Special Patient Groups
Pregnancy
Category D. Used for prevention and treatment of seizures in pre-eclampsia and eclampsia. Prolonged use (more than 5-7 days) during pregnancy can lead to fetal bone abnormalities (osteopenia, fractures) and neonatal hypocalcemia/hypermagnesemia. Use only when clearly indicated and for the shortest duration possible.
Trimester-Specific Risks:
First Trimester:
Limited data, generally not used unless severe, life-threatening hypomagnesemia.
Second Trimester:
Used for pre-eclampsia/eclampsia. Risk of fetal bone abnormalities with prolonged use.
Third Trimester:
Used for pre-eclampsia/eclampsia. Risk of fetal bone abnormalities with prolonged use. Neonatal respiratory depression and hypotonia if given close to delivery.
Lactation
L3 (Moderately safe). Magnesium is naturally present in breast milk. While magnesium sulfate is excreted into breast milk, the amount is generally considered low and unlikely to cause adverse effects in a healthy, full-term infant. Monitor infant for signs of sedation or diarrhea.
Infant Risk:
Low risk for healthy, full-term infants. Monitor for sedation, hypotonia, or diarrhea.
Pediatric Use
Use with caution. Dosing is weight-based and varies by indication. Close monitoring of serum magnesium, vital signs, and reflexes is crucial due to increased risk of toxicity, especially in neonates and infants with immature renal function.
Geriatric Use
Use with caution. Elderly patients are more likely to have impaired renal function, which increases the risk of magnesium accumulation and toxicity. Lower doses and closer monitoring of renal function, serum magnesium levels, and clinical signs of toxicity (e.g., diminished reflexes, respiratory depression) are recommended.
Clinical Information
Clinical Pearls
- Always have calcium gluconate (10% solution) readily available as an antidote for magnesium toxicity.
- Monitor deep tendon reflexes, respiratory rate, and urine output hourly during continuous IV infusion for pre-eclampsia/eclampsia.
- Ensure adequate renal function before and during magnesium sulfate administration.
- Be aware of the potential for additive CNS depression when co-administering with other sedatives or narcotics.
- For pre-eclampsia/eclampsia, magnesium sulfate is the drug of choice for seizure prophylaxis and treatment, not for blood pressure control.
- The 10mg/ml concentration means 100ml contains 1000mg (1g) of magnesium sulfate. Ensure correct calculation for bolus and infusion rates.
Alternative Therapies
- For eclampsia/pre-eclampsia: Antihypertensives (e.g., Labetalol, Hydralazine) for blood pressure control, but not for seizure prophylaxis/treatment.
- For hypomagnesemia: Oral magnesium supplements (for mild cases).
- For severe asthma: Systemic corticosteroids, inhaled beta-agonists, anticholinergics.
Cost & Coverage
Average Cost:
Highly variable, typically low cost for generic IV solutions. per 100ml bag
Generic Available:
Yes
Insurance Coverage:
Tier 1 (Generic)
General Drug Facts
If your symptoms or health problems do not improve or worsen over time, it is essential to contact your doctor for further evaluation and guidance. To ensure safe and effective treatment, never share your medication with others, and do not take medication prescribed to someone else.
Store all medications in a secure location, out of the reach of children and pets, to prevent accidental ingestion or exposure. Properly dispose of unused or expired medications by throwing them away. However, do not flush medications down the toilet or pour them down the drain unless specifically instructed to do so by a healthcare professional or pharmacist. If you are unsure about the correct disposal method, consult with your pharmacist, who can provide guidance on the best approach. Additionally, you may want to inquire about potential drug take-back programs in your area.
Some medications may include an additional patient information leaflet, so it is a good idea to check with your pharmacist to see if this is the case. If you have any questions or concerns about your medication, do not hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider for clarification and support.
In the event of a suspected overdose, it is crucial to seek immediate medical attention or contact your local poison control center. Be prepared to provide detailed information about the overdose, including the type of medication taken, the amount, and the time it occurred, to ensure prompt and effective treatment.
Store all medications in a secure location, out of the reach of children and pets, to prevent accidental ingestion or exposure. Properly dispose of unused or expired medications by throwing them away. However, do not flush medications down the toilet or pour them down the drain unless specifically instructed to do so by a healthcare professional or pharmacist. If you are unsure about the correct disposal method, consult with your pharmacist, who can provide guidance on the best approach. Additionally, you may want to inquire about potential drug take-back programs in your area.
Some medications may include an additional patient information leaflet, so it is a good idea to check with your pharmacist to see if this is the case. If you have any questions or concerns about your medication, do not hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider for clarification and support.
In the event of a suspected overdose, it is crucial to seek immediate medical attention or contact your local poison control center. Be prepared to provide detailed information about the overdose, including the type of medication taken, the amount, and the time it occurred, to ensure prompt and effective treatment.