Magnesium sulfate heptahydrate

What Magnesium sulfate heptahydrate is used for

Quoted from the “Indications and Usage” section of the FDA-approved label.

Magnesium Sulfate in Water for Injection is indicated for the prevention and control of seizures in pre-eclampsia and eclampsia, respectively. When used judiciously it effectively prevents and controls the convulsions of eclampsia without producing deleterious depression of the central nervous system of the mother or infant. However, other effective drugs are available for this purpose.

— FDA label: Magnesium Sulfate in Water, Hospira, Inc., effective August 24, 2026. Read the full label on DailyMed →

Label quoted: the one for the most common form (injection, solution, intravenous), Magnesium Sulfate in Water, Hospira, Inc.; it covers 5 products in the FDA NDC Directory. The side effects, interactions, dosage and pregnancy quotes below come from this same label.

The FDA has 38 labels for products of this medicine (different makers and forms); uses can differ between them. Check the label that comes with your own medicine.

This page is not medical advice. Talk to your doctor or pharmacist before you start, stop or change any medicine.

Boxed warning

A boxed warning (“black box”) is the FDA’s strongest warning on a drug label, for serious or life-threatening risks.

The label quoted above has no boxed warning.

0 of 38 FDA labels for this medicine have a boxed warning.

Magnesium sulfate heptahydrate side effects

Quoted from the “Adverse Reactions” section of the FDA-approved label. Tell your doctor about any side effect that worries you.

The adverse effects of parenterally administered magnesium usually are the result of magnesium intoxication. These include flushing, sweating, hypotension, depressed reflexes, flaccid paralysis, hypothermia, circulatory collapse, cardiac and central nervous system depression proceeding to respiratory paralysis. Hypocalcemia with signs of tetany secondary to magnesium sulfate therapy for eclampsia has been reported.

— FDA label: Magnesium Sulfate in Water, Hospira, Inc., effective August 24, 2026. Read the full label on DailyMed →

Magnesium sulfate heptahydrate dosage

Quoted from the “Dosage and Administration” section of the FDA-approved label. Your own dose is the one your doctor prescribes: do not change it on your own.

Magnesium Sulfate in Water for Injection is intended for intravenous use only. For the management of pre-eclampsia or eclampsia, intravenous infusions of dilute solutions of magnesium (1% to 8%) are often given in combination with intramuscular injections of 50% Magnesium Sulfate Injection, USP. Therefore, in the clinical conditions cited below, both forms of therapy are noted, as appropriate.

Read more of this section

Continuous maternal administration of magnesium sulfate in pregnancy beyond 5-7 days can cause fetal abnormalities. In Eclampsia In severe pre-eclampsia or eclampsia, the total initial dose is 10 to 14 g of magnesium sulfate. To initiate therapy, 4 g of Magnesium Sulfate in Water for Injection may be administered intravenously. The rate of I.V. infusion should generally not exceed 150 mg/minute, or 3.75 mL of a 4% concentration (or its equivalent) per minute, except in severe eclampsia with seizures. Simultaneously, 4 to 5 g (32.5 to 40.6 mEq) of magnesium sulfate may be administered intramuscularly into each buttock using undiluted 50% Magnesium Sulfate Injection, USP. After the initial I.V. dose, some clinicians administer 1 to 2 g/hour by constant I.V. infusion. Subsequent intramuscular doses of 4 to 5 g of magnesium sulfate may be injected into alternate buttocks every 4 hours, depending on the continuing presence of the patellar reflex, adequate respiratory function, and absence of signs of magnesium toxicity. Therapy should continue until paroxysms cease. A serum magnesium level of 6 mg/100 mL is considered optimal for control of seizures. A total daily (24 hr) dose of 30 to 40 g magnesium sulfate should not be exceeded. In the presence of severe renal insufficiency, frequent serum magnesium concentrations must be obtained and the maximum dosage of magnesium sulfate is 20 g per 48 hours. Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. Do not administer unless solution is clear. Discard unused portion.

— FDA label: Magnesium Sulfate in Water, Hospira, Inc., effective August 24, 2026. Read the full label on DailyMed →

Magnesium sulfate heptahydrate in pregnancy

Quoted from the pregnancy part of the FDA-approved label. Ask your doctor before you take any medicine while pregnant or planning a pregnancy.

(See WARNINGS and PRECAUTIONS)

— FDA label: Magnesium Sulfate in Water, Hospira, Inc., effective August 24, 2026. Read the full label on DailyMed →

Magnesium sulfate heptahydrate and breastfeeding

Quoted from the nursing mothers / lactation part of the FDA-approved label.

It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when Magnesium Sulfate in Water for Injection is administered to a nursing mother.

— FDA label: Magnesium Sulfate in Water, Hospira, Inc., effective August 24, 2026. Read the full label on DailyMed →

When Magnesium sulfate heptahydrate should not be used

Quoted from the “Contraindications” section of the FDA-approved label.

Intravenous magnesium should not be given to mothers with toxemia of pregnancy during the 2 hours preceding delivery.

— FDA label: Magnesium Sulfate in Water, Hospira, Inc., effective August 24, 2026. Read the full label on DailyMed →

Magnesium sulfate heptahydrate overdose

Quoted from the “Overdosage” section of the FDA-approved label. If someone may have taken too much, call Poison Help at 1-800-222-1222 (or 911 in an emergency).

Magnesium intoxication is manifested by a sharp drop in blood pressure and respiratory paralysis. Disappearance of the patellar reflex is a useful clinical sign to detect the onset of magnesium intoxication. In the event of overdosage, artificial ventilation must be provided until a calcium salt can be injected IV to antagonize the effects of magnesium. For Treatment of Overdose Artificial respiration is often required.

Read more of this section

Intravenous calcium, 10 to 20 mL of a 5% solution (diluted if desirable) with isotonic sodium chloride for injection) is used to counteract effects of hypermagnesemia. Subcutaneous physostigmine, 0.5 to 1 mg may be helpful. Hypermagnesemia in the newborn may require resuscitation and assisted ventilation via endotracheal intubation or intermittent positive pressure ventilation as well as IV calcium.

— FDA label: Magnesium Sulfate in Water, Hospira, Inc., effective August 24, 2026. Read the full label on DailyMed →

Forms and how it is given

Same medicine, other forms and combinations

Prescription medicine pages on this site that share an active ingredient with this one, from the FDA NDC Directory. A combination is a different medicine: ask your pharmacist before you switch.

Other medicines that contain Magnesium sulfate heptahydrate

• Sodium sulfate, potassium sulfate, magnesium sulfateSuprep Bowel Prep, Sodium Sulfate, Potassium Sulfate, and Magnesium Sulfate Bowel Prep Kit · 17 products

Companies that list this medicine

Labelers in the FDA NDC Directory: the company named on the package (maker or distributor), with the number of prescription products.

• Fresenius Kabi USA, LLC9 products
• WG Critical Care, LLC8 products
• Hospira, Inc.8 products
• Baxter Healthcare Corporation5 products
• B. Braun Medical Inc.4 products
• HF Acquisition Co LLC, DBA HealthFirst4 products
• Henry Schein, Inc.3 products
• Medical Purchasing Solutions, LLC3 products
• ProPharma Distribution2 products
• Athenex Pharmaceutical Division, LLC.2 products
• Avenacy, LLC2 products
• Gland Pharma Limited2 products
• Amneal Pharmaceuticals LLC2 products
• Remedyrepack Inc.1 product
• Camber Pharmaceuticals, Inc.1 product
• Sun Pharmaceutical Industries, Inc.1 product
• Civica, Inc.1 product
• Sagent Pharmaceuticals1 product
• HF Acquisition Co. LLC, DBA Health First1 product

FDA approval history

• NDA: New Drug Application: how a new (usually brand-name) medicine is approved.
• ANDA: Abbreviated New Drug Application: how a generic version is approved.

Generic approvals (14)

• ANDA075151Hospira · April 25, 2000
• ANDA202411Hospira · May 14, 2015
• ANDA207349Hq Spclt Pharma · March 2, 2016
• ANDA206486Fresenius Kabi USA · March 7, 2016
• ANDA206485Fresenius Kabi USA · March 15, 2016
• ANDA207350Hq Spclt Pharma · December 6, 2017
• ANDA211966Baxter Hlthcare Corp · June 1, 2020
• ANDA213917Gland · July 10, 2020
• ANDA211965Baxter Hlthcare Corp · August 11, 2020
• ANDA207966B Braun Medical · October 27, 2020
• ANDA207967B Braun Medical · April 26, 2021
• ANDA209642Milla Pharms · November 8, 2021
• ANDA216597Amneal · February 15, 2023
• ANDA219777Aspiro · May 28, 2025

Shortage status

The FDA drug shortage list does not show these products.

FDA Drug Shortages database →

Recalls

From FDA enforcement reports, matched by the product’s NDC code. A recall usually covers specific lots only: check the lot number on your package and ask your pharmacist. Do not stop a medicine on your own.

1. March 18, 2026 · Class I · Ongoing · D-0478-2026

   Product mix up: a foil pouch labeled "Magnesium Sulfate in Water for Injection, 4 g/100 mL" actually contained an IV bag of Tranexamic Acid instead.

   Magnesium Sulfate in Water for Injection, 4g/100 mL (40mg/mL) IV bag, further packaged in cartons of 12 x 100 mL IV bags, Rx only, Manufactured by: Amneal Pharmaceuticals Pvt. Ltd., Ahmedabad, 382110, India, Distributed — Amneal Pharmaceuticals, LLC

2. October 3, 2018 · Class II · Terminated · D-0015-2019

   Correct Labeled Product Mispack: confirmed report involving a single unit of properly labeled Heparin in 0.45% Sodium Chloride for Injection (NDC 0409-7651-03, Lot 87903FW) that was found inside a case of Magnesium Sulfate in Water for Injection.

   Magnesium Sulfate in Water for Injection (0.325 mEq Mg++/mL) 40 mg/mL, 20 g Total, 500 mL Single-Dose Container bag, Rx only, Hospira, Inc. Lake Forest, IL 60045 USA, NDC 0409-6729-03. — Pfizer Inc.

3. March 23, 2016 · Class I · Ongoing · D-1137-2016

   Presence of Particulate Matter: Confirmed customer complaint for the presence of particulate matter.

   Magnesium Sulfate Inj., USP 50%, 10 g/20 mL (0.5 g/mL), (4 mEq Magnesium/mL, 20 mL Single-dose vial, packaged in 25 vials per box, Rx Only, Hospira, Inc., Lake Forest, IL 60045, NDC 0409-2168-02, barcode (01) 2 030409 21 — Hospira Inc.

4. March 23, 2016 · Class III · Ongoing · D-0854-2016

   Failed pH Specifications: Confirmed high out of specification (OOS) results for pH.

   Magnesium Sulfate Inj., USP 50%, 10 g/20 mL (0.5 g/mL), (4 mEq Magnesium/mL, 20 mL Single-dose vial, packaged in 25 vials per box, Rx Only, Hospira, Inc., Lake Forest, IL 60045, NDC 0409-2168-02, barcode (01) 2 030409 21 — Hospira Inc.

5. January 5, 2016 · Class I · Terminated · D-0668-2016

   Labeling: Incorrect Barcode: Primary bag labeling may be mislabeled with the wrong barcode which scans in as heparin sodium.

   Magnesium Sulfate in Water for Injection, (0.325 mEq Mg++/mL) 40 mg/mL, 2 g Total, 50 mL Single-Dose Container bag, Hospira, Inc., Lake Forest, IL 60045, NDC 0409-6729-24. — Hospira Inc.

6. May 19, 2015 · Class III · Terminated · D-1232-2015

   Failed pH Specifications: 12 month stability testing

   Magnesium Sulfate Injection, USP, 50%, 20mL, Single dose Fliptop Vial, For IV or IM use, Rx only, Manufactured by Hospira, Inc. 4285 Wesleyan Blvd Rocky Mount, NC 27804 for Hospira, Inc. 275 N Field Drive, Lake Forest, I — Hospira Inc.

7. March 6, 2015 · Class I · Terminated · D-1076-2015

   Labeling: Wrong Bar Code: There is a potential for some units to be mislabeled with an incorrect barcode on the immediate container that scans as heparin sodium 2000 USP units/1000 mL in 0.9% in sodium chloride injection.

   MAGNESIUM SULFATE IN 5% DEXTROSE INJECTION, USP, 10 mg/mL; 100 mL bag, Rx only, Hospira, Inc., Lake Forest, IL 60045, NDC 0409-6727-23, UPC (01) 0 030409 672723 1. — Hospira Inc.

8. May 25, 2013 · Class I · Terminated · D-920-2013

   Presence of Particulate Matter: Glass particulate matter was observed in a retention sample during an annual review.

   Magnesium Sulfate Injection, USP, 50% (25 grams/50 mL), For IM or IV Use, 50 mL, Single Dose Vial, Rx only, Preservative Free, APP Pharmaceuticals, LLC, Schaumburg, IL, 60173, NDC 63323-064-50 — Fresenius Kabi USA, LLC

9. April 5, 2012 · Class III · Terminated · D-1390-2012

   Superpotent (Single Ingredient) Drug: Above specification assay results for percentage of magnesium sulfate.

   Magnesium Sulfate in Water for Injection, 40 mg/mL (0.325 mEq Mg++/mL), 2 g total, 50 mL Flexible Container, Rx only, Hospira, Inc., Lake Forest, IL 60045; NDC 0409-6729-24. — Hospira, Inc.

Official identifiers

Next steps

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• Latest FDA drug recallsAll medicines, newest first
• Magnesium sulfate sold over the counterDrug Facts label and store brands
• Fresenius Kabi USA, LLCMaker or distributor
• WG Critical Care, LLCMaker or distributor
• Hospira, Inc.Maker or distributor
• All prescription drugs A to ZSearch by generic, brand or Spanish name

Sources

1. FDA-approved label on DailyMed (National Library of Medicine) — Magnesium Sulfate in Water, Hospira, Inc., effective August 24, 2026; via openFDA, FDA data exported October 30, 2026, retrieved October 31, 2026
2. NDC Directory (openFDA) — U.S. Food and Drug Administration (FDA), FDA data exported October 30, 2026, retrieved October 31, 2026
3. Drugs@FDA (openFDA) — U.S. Food and Drug Administration (FDA), FDA data exported October 30, 2026, retrieved October 31, 2026
4. Drug recall enforcement reports (openFDA) — U.S. Food and Drug Administration (FDA), FDA data exported October 27, 2026, retrieved October 31, 2026
5. Drug shortages (openFDA) — U.S. Food and Drug Administration (FDA), FDA data exported October 30, 2026, retrieved October 31, 2026

openFDA data is provided by the FDA as is; it may be incomplete. Always rely on the label that comes with your medicine. FDA Enforcement Report search →

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