Magnesium Sulfate 80mg/ml Inj, 50ml
Overview
What is this medicine?
How to Use This Medicine
To use this medication correctly, follow your doctor's instructions and read all the information provided. It's essential to follow the instructions carefully. This medication is administered either 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 best way to store it.
Missing a Dose
If you miss a dose, contact your doctor to find out what steps to take next.
Lifestyle & Tips
- Report any unusual symptoms immediately, such as difficulty breathing, muscle weakness, or feeling very drowsy.
- Inform healthcare providers about all medications you are taking, especially other sedatives or muscle relaxants.
- Maintain adequate hydration as advised by your doctor.
Available Forms & Alternatives
Available Strengths:
- Magnesium Oxide 400mg Tablets
- Magnesium Sulfate 50% Inj, 10ml
- Magnesium 500mg Tablets
- Magnesium Sulfate 40mg/ml Inj, 50ml
- Magnesium Chloride 20% Inj, 50ml
- Magnesium Sulf 40mg/ml Inj, 100ml
- Magnesium Sulfate 50% Inj, 50ml
- Magnesium 200mg Tablets
- Magnesium Sulfate 50% Inj, 2ml
- Magnesium 300mg Capsules
- Magnesium Sulfate 40mg/ml Inj, 50ml
- Magnesium Sulfate 80mg/ml Inj, 50ml
- Magnesium 250mg Tablets
- Magnesium Sulfate 80mg/ml Inj
- Magn Sulf/d5w 10mg/ml Inj, 100ml
- Magnesium Oxide 250mg Tablets
- Magnesium Citrate Soln Lemon 296ml
- Magnesium Sulfate 50% Inj, 20ml
- Magnesium Su 40g/1000ml Inj, 1000ml
- Magnesium Sulfate 20gm/500ml Inj
Dosing & Administration
Adult Dosing
Condition-Specific Dosing:
Pediatric Dosing
Dose Adjustments
Renal Impairment:
Hepatic Impairment:
Pharmacology
Mechanism of Action
Pharmacokinetics
Absorption:
Distribution:
Elimination:
Pharmacodynamics
Safety & Warnings
BLACK BOX WARNING
Side Effects
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 attention immediately:
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 can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to contact your doctor or seek medical help if you have any side effects that bother you or do not go away. Not all possible side effects are listed here. If you have questions or concerns about side effects, consult your doctor.
You can report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch. Your doctor can also provide medical advice about side effects.
Seek Immediate Medical Attention If You Experience:
- Difficulty breathing or slow breathing
- Extreme drowsiness or confusion
- Severe muscle weakness or inability to move
- Absent reflexes (e.g., knee jerk)
- Dizziness or lightheadedness (sign of low blood pressure)
- Blurred or double vision
- Slurred speech
Before Using This Medicine
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 potential interactions. To ensure your safety, it is crucial to disclose all of your medications, including prescription and over-the-counter drugs, natural products, and vitamins, as well as any health problems you may have. Your doctor and pharmacist need this information to determine whether it is safe for you to take this medication in conjunction with your other treatments.
Remember, do not start, stop, or modify the dosage of any medication without first consulting your doctor to confirm that it is safe to do so.
Precautions & Cautions
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 discuss any concerns or questions you may have.
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, you should contact your doctor immediately, 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:
- Hypotension (low blood pressure)
- Nausea, vomiting
- Flushing, sweating
- CNS depression (drowsiness, confusion, coma)
- Respiratory depression (slow, shallow breathing, apnea)
- Loss of deep tendon reflexes
- Muscle weakness, paralysis
- Bradycardia (slow heart rate)
- Cardiac arrest
What to Do:
Immediate discontinuation of magnesium sulfate. Administer intravenous calcium gluconate (10 mL of 10% solution) slowly to counteract magnesium's effects. Provide respiratory support (e.g., mechanical ventilation) if needed. IV fluids to promote renal excretion. 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) - increased risk of hypotension and neuromuscular blockade.
- Neuromuscular blocking agents (e.g., succinylcholine, rocuronium, vecuronium) - potentiates and prolongs neuromuscular blockade.
Major Interactions
- CNS depressants (e.g., opioids, benzodiazepines, barbiturates, general anesthetics) - additive CNS depression, respiratory depression.
- Digoxin - increased risk of cardiac conduction abnormalities (though magnesium can be used to treat digoxin-induced arrhythmias).
Moderate Interactions
- Diuretics (loop and thiazide) - may increase renal excretion of magnesium, potentially leading to hypomagnesemia (if not the reason for administration).
- Aminoglycosides - may potentiate neuromuscular blockade.
Minor Interactions
- Not available
Monitoring
Baseline Monitoring
Rationale: To establish baseline and guide initial dosing, especially in hypomagnesemia or renal impairment.
Timing: Prior to initiation of therapy.
Rationale: Magnesium is renally excreted; impaired renal function increases risk of toxicity.
Timing: Prior to initiation of therapy.
Rationale: Magnesium can cause hypotension.
Timing: Prior to initiation of therapy.
Rationale: High magnesium levels can cause respiratory depression.
Timing: Prior to initiation of therapy.
Rationale: Loss of DTRs is an early sign of magnesium toxicity.
Timing: Prior to initiation of therapy.
Routine Monitoring
Frequency: Every 4-6 hours during continuous infusion, or as clinically indicated.
Target: 4-7 mg/dL (therapeutic for eclampsia); 1.5-2.5 mg/dL (normal range)
Action Threshold: >7 mg/dL (toxicity risk), >12 mg/dL (respiratory depression), >15 mg/dL (cardiac arrest)
Frequency: Every 15-30 minutes during loading dose, then hourly during maintenance infusion.
Target: Individualized, maintain adequate perfusion.
Action Threshold: Significant hypotension (e.g., SBP <90 mmHg or symptomatic hypotension)
Frequency: Every 15-30 minutes during loading dose, then hourly during maintenance infusion.
Target: >12 breaths/min
Action Threshold: <12 breaths/min (sign of toxicity)
Frequency: Every 15-30 minutes during loading dose, then hourly during maintenance infusion.
Target: Present (e.g., 1+ or 2+)
Action Threshold: Absent patellar reflexes (sign of toxicity)
Frequency: Hourly
Target: >25-30 mL/hour
Action Threshold: <25 mL/hour (indicates impaired renal excretion and increased toxicity risk)
Frequency: Consider with rapid infusion or high doses, or in patients with cardiac disease.
Target: Normal rhythm, PR/QRS/QT intervals
Action Threshold: Prolonged PR, QRS, QT intervals; heart block; bradycardia
Symptom Monitoring
- Flushing
- Sweating
- Drowsiness
- Muscle weakness
- Slurred speech
- Blurred vision
- Hypotension
- Respiratory depression
- Loss of deep tendon reflexes
- Cardiac arrhythmias
Special Patient Groups
Pregnancy
Category D. Used for prevention and treatment of seizures in preeclampsia and eclampsia. Prolonged use (more than 5-7 days) for preterm labor has been associated with fetal bone abnormalities (hypocalcemia, osteopenia) and should be avoided unless benefits clearly outweigh risks. Short-term use for neuroprotection in preterm labor is common.
Trimester-Specific Risks:
Lactation
Magnesium is naturally present in breast milk. Excretion into breast milk is minimal and unlikely to cause adverse effects in a healthy, full-term infant. Considered compatible with breastfeeding when used therapeutically.
Pediatric Use
Dosing is weight-based. Close monitoring of magnesium levels, vital signs, and reflexes is crucial due to varying renal function and sensitivity. Used for hypomagnesemia, severe acute asthma, and sometimes for specific cardiac arrhythmias.
Geriatric Use
Use with caution due to potential for age-related decline in renal function, which increases the risk of magnesium toxicity. Start with lower doses and monitor closely for signs of toxicity (e.g., hypotension, respiratory depression, CNS depression, loss of reflexes).
Clinical Information
Clinical Pearls
- Always have calcium gluconate (10% solution) readily available as an antidote for magnesium toxicity.
- Closely monitor deep tendon reflexes, respiratory rate, blood pressure, and urine output as these are key indicators of magnesium toxicity.
- Magnesium sulfate is a high-alert medication; ensure correct dose, concentration, and infusion rate.
- In patients with renal impairment, significant dose reduction is necessary to prevent accumulation and toxicity.
- For eclampsia, the goal is to maintain therapeutic magnesium levels (4-7 mg/dL) to prevent seizures, not necessarily to normalize blood pressure.
- IV magnesium should always be administered via infusion pump, never as a rapid IV push (except for specific emergency situations like Torsades de Pointes).
Alternative Therapies
- For eclampsia/preeclampsia: Antihypertensives (e.g., labetalol, hydralazine) for blood pressure control, but magnesium is specific for seizure prevention.
- For hypomagnesemia: Oral magnesium supplements (for mild cases).
- For acute asthma: Beta-agonists, corticosteroids, anticholinergics.
- For Torsades de Pointes: Electrical cardioversion, isoproterenol, overdrive pacing.