Magnesium sulfate

The medical product Magnesium sulfate - bitter salt, magnesium sulfate - is a cardiovascular drug that is widely prescribed to stabilize blood pressure - in particular, during an attack of hypertension.

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Indications Magnesium sulfate

The spectrum of use of magnesium sulfate is quite wide:

• attack of hypertension (crisis);
• ventricular tachyarrhythmia;
• convulsive states;
• eclamptic state;
• low magnesium content;
• accelerated consumption of magnesium in the body.

Magnesium sulfate is often used in combination with other medications for premature labor, heart failure, intoxication with heavy metal salts, lead, and barium salts.

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Release form

Magnesium sulfate is produced as an injectable drug, which is a clear, colorless liquid substance.

The composition of the liquid is represented by magnesium sulfate heptahydrate, which contains 250 mg in 1 ml.

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Pharmacodynamics

Magnesium is very important for the human body:

• exhibits calcium antagonist properties;
• takes part in most metabolic processes;
• reduces the production of catecholamines;
• stabilizes neurochemical impulses, excitability of the muscular system;
• reduces the level of acetylcholine in the central and peripheral nervous system;
• helps eliminate pain, cramps, spasms, etc.

In addition, the introduction of magnesium sulfate leads to the expansion of arterial vessels, lowers blood pressure, reduces the load on the heart muscle, and stops the reaction of reperfusion injury of the heart muscle.

Magnesium prevents blood thickening and thrombus formation – this is explained by a decrease in the production of thromboxane A ₂, activation of the production of prostacyclin and high-density lipoproteins.

Large amounts of magnesium may result in adverse isotropic effects and smooth muscle relaxation.

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Pharmacokinetics

After the injection procedure, magnesium sulfate quickly enters the tissue structures and body fluids, simultaneously penetrating the blood-brain barrier, through the placenta, and ending up in breast milk.

Magnesium sulfate is excreted through the kidneys.

The systemic effect of the drug is detected within 60 seconds after intravenous injection and 60 minutes after intramuscular injection. Duration of action:

• after intravenous infusion – half an hour;
• after intramuscular injection – up to 4 hours.

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Dosing and administration

Magnesium sulfate is used by injection, according to individual regimens:

• In case of magnesium deficiency in the body, 4 ml of the drug is administered intramuscularly every 6 hours.
• For high blood pressure, 5 to 20 ml of the medication is administered intramuscularly daily, in a course of 15-20 injections.
• In case of hypertension (crisis), 10 to 20 ml is administered intramuscularly or intravenously slowly.
• In case of cardiac arrhythmia, intravenous administration of 4-8 ml of the drug is used over 5-10 minutes. If necessary, the infusion is repeated.
• For ischemic stroke, intravenous injections of 10-20 ml of the medication are used daily for a week.
• To relieve convulsive syndrome, 5 to 20 ml is used in the form of intramuscular injections.
• Patients with toxicosis of pregnancy are administered 10-20 ml up to 2 times a day intramuscularly.
• To relieve pain during labor, 5 to 20 ml is administered intramuscularly.
• Heavy metal poisoning is treated with intravenous infusion of 5-10 ml of Magnesium sulfate.

Use Magnesium sulfate during pregnancy

Pregnant women are only recommended to take magnesium sulfate in extreme cases, if the expected effect of the medication outweighs the possible danger to the fetus.

Injection of Magnesium sulfate before or during labor may affect the contractility of the uterine muscles. This must be taken into account and be prepared to use medications to stimulate labor.

Breastfeeding is discontinued during treatment with Magnesium sulfate.

Contraindications

Magnesium sulfate should not be used:

• in case of hypersensitivity to the composition of the drug;
• with low blood pressure;
• with a slow heart rate (less than 55 beats/min.);
• in atrioventricular block;
• if there is a lack of calcium in the body;
• in case of depressed respiratory function;
• when exhausted;
• in case of obvious renal dysfunction;
• in case of severe liver damage;
• for muscle weakness;
• in oncological pathologies.

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Side effects Magnesium sulfate

Treatment with Magnesium sulfate may be accompanied by unexpected side effects:

• a significant decrease in blood pressure, a slowing of the heart rate, arrhythmia, a comatose state, and even cardiac arrest;
• shortness of breath, depression of respiratory function;
• headaches, dizziness, a feeling of fatigue, drowsiness, impaired consciousness, anxiety, trembling in the limbs and fingers;
• muscle weakness;
• dyspepsia;
• allergies;
• redness of the skin, rash, itching;
• increase in daily diuresis;
• atony of the uterus;
• decreased blood calcium levels, hyperosmolar dehydration;
• swelling and reaction at the injection site.

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Overdose

Possible signs of infusion of too large a volume of Magnesium Sulfate may include:

• weakening and disappearance of tendon reflexes;
• ECG changes – prolonged PQ and widened QRS;
• respiratory depression;
• arrhythmia;
• changes in cardiac conduction up to and including cardiac arrest.

Additional symptoms may include increased sweating, anxiety, general lethargy, increased daily diuresis, and uterine atony.

Treatment is carried out with calcium-based drugs - they are administered intravenously, slowly. Additional use of diuretics, cardiovascular agents, oxygen inhalations, artificial intravenous line, and in severe situations - peritoneal dialysis or hemodialysis is possible.

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Interactions with other drugs

The injectable agent Magnesium sulfate enhances the effect of medications that inhibit processes in the central nervous system (narcotic and non-narcotic analgesics).

Combined treatment with muscle relaxants and Nifedipine enhances neuromuscular blockade.

Sleeping pills, narcotics and antihypertensive medications in combination with Magnesium sulfate may affect respiratory depression.

Cardiac glycosides can cause cardiac arrhythmia.

In combination with magnesium sulfate, the effectiveness of antithrombotic drugs, Isoniazid, MAO inhibitors, and vitamin K antagonists is reduced.

There are cases of delayed elimination of Mexiletine.

When Magnesium sulfate is combined with Propafenone, the effect of the two medications is enhanced, but their toxicity also increases.

Magnesium sulfate negatively affects the absorption of tetracycline antimicrobial agents and weakens the effects of Tobramycin and Streptomycin.

Magnesium sulfate is chemically incompatible with calcium solutions, ethyl alcohol, carbonates, alkaline phosphates, arsenic, strontium, salicylates, and hydrocarbonates.

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Storage conditions

Magnesium sulfate is stored in its original packaging, in rooms with temperatures up to +25°C, in places inaccessible to children.

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Shelf life

Magnesium sulfate can be stored for up to 2 years under appropriate conditions.

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