When administered parenterally has a sedative, diuretic, arteriodilatirtee, anticonvulsant, anti-arrhythmic, hypotensive, antispasmodic, in large doses – kurarepodobnoe andriol (depressant effect on neuromuscular transmission), tocolytic, hypnotic and narcotic effect, suppresses the respiratory center. Magnesium is a physiological calcium antagonist and is able to displace it from the binding sites. It regulates metabolism, interneuron transmission and muscle excitability, prevents the entry of calcium through the presynaptic membrane, reduces the amount of acetylcholine in the peripheral nervous system and central nervous system (CNS). It relaxes smooth muscles, lowers blood pressure (BP) (preferably high), enhances diuresis. Anticonvulsant action – magnesium reduces the release of acetylcholine from neuromuscular synapses, thus inhibiting neuromuscular transmission, has a direct inhibitory effect on the central nervous system. Antiarrhythmic action – magnesium reduces the excitability of muscle cells, restores the ionic balance, stabilizes cell membranes, violates the sodium current, slow incoming . calcium current and unilateral current potassiumcardioprotective effect caused by expansion of the coronary artery, reducing the total peripheral vascular resistance and platelet aggregation. tocolytic action – magnesium inhibits contractility of the myometrium (decreased absorption, binding and calcium distribution in smooth muscle cells), enhances blood flow to the uterus resulting expansion of its receptacles. Is an antidote for poisoning by heavy metal salts. Systemic effects occur almost immediately after intravenous (i / v) and 1 hour after intramuscular (i / m) administration. The duration of the on / in the introduction – 30 minutes with the / m – 3-4 hours. Pharmacokinetics Equilibrium concentration (Css) – 2-3,5 mmol / l. It penetrates the blood-brain and placental barriers, creates breast milk concentration is 2 times higher than plasma concentrations.Derivation is performed by the kidneys, renal excretion is proportional to the velocity of the plasma concentration and glomerular filtration rate.
Arterial hypertension (including hypertensive crisis with brain swelling phenomena), polymorphic ventricular tachycardia (type “pirouette”), convulsions (to suppress seizures in eclampsia, to prevent seizures in severe pre-eclampsia; for removal of strong uterine contractions ), poisoning by salts of heavy metals (mercury, arsenic, tetraethyl lead), hypomagnesemia (including an increased need for magnesium and acute hypomagnesemia – tetany).
Hypersensitivity to the drug; atrioventricular block I-III degree (AV block); severe renal impairment (creatinine clearance less than if the 20 ml / min); severe hypotension; conditions associated with calcium deficiency and depression of the respiratory center; bradycardia; prenatal period (2 hours before delivery). Precautions: myasthenia gravis, chronic renal failure (if creatinine clearance 20 mL / min), respiratory disease, acute inflammatory diseases of the gastrointestinal tract, elderly age, pregnancy, lactation, children’s age.
Dosage and administration
Doses clarify the subject of the therapeutic effect and the concentration of magnesium ions in the blood serum. Pre-eclampsia and eclampsia. The dose is determined individually, depending on the clinical situation. Saturation dose – 2-4 g 5-20 min (infusion). Supporting dose-1-2 g per hour. Uterine tetany. Saturation dose – 4 g every 20 minutes (infusion). Maintenance dose – again – 1-2 g per hour, later – 1 g per hour (infusion can be administered 24-72 hours). Hypomagnesemia. In newborns. Daily dose – 0.2-0.8 mg / kg / slow . In adults. Easy. Magnesium sulfate solution is used parenterally, when possible or impractical oral route magnesium drugs (because of nausea, emesis, disorders of bone resorption in the stomach and others.). The daily dose – 1-2 g / m. This dose is administered once or in 2-3 divided doses. Place of introduction should be changed. Hard. The initial dose – 5 g dose is poured into 1 liter of infusion solution and slowly introduced into / in. Dosed depending on the serum concentration of the drug. Prevention hypomagnesemia in patients receiving parenteral nutrition only. If no magnesium in nutrient solutions, it was added additionally. The daily dose – usually 1.5-4 g in 1 L of parenteral nutrition solution was added 1 g of magnesium sulfate. The maximum daily dose of magnesium sulfate for adults – 40 g In PNDS crises injected in / in (slow !!) 5-20 ml of 25% magnesium sulfate solution. For edema arrhythmias / injected 1-2 g for about five minutes, possibly repeated administration. Dosages of magnesium sulphate are listed in grams. They correspond to the amount of solution: 1 g – 4 ml (25%); R 2 – 8 ml (25%); 3 g – 12 ml (25%); 4 g – 16 ml (25%); 5 g – 20 ml (25%); 10 g – 40 ml (25%); 15 g – 60 ml (25%); 20 g – 80 ml (25%); 30 g – 120 ml (25%); . 40 g – 160 ml (25%), magnesium sulfate solution was diluted in ampoules injectable solutions: 0.9% sodium chloride or 5% dextrose (glucose).
Slowing the rate of respiration; dyspnea; acute circulatory failure; weakening of reflexes; hyperemia; hypotension; hypothermia; weakening of muscle tone; uterine atony; rash; anxiety; severe sedation;polyuria; slowing of the heart rate; changes in the electrocardiogram. The andriol drug reduces the excitability of the respiratory center, large doses of the drug when administered parenterally can easily cause paralysis of the respiratory center.
Early signs and gipermagniemii symptoms: bradycardia, diplopia, a sudden rush of blood to the face, headache, decreased blood pressure, nausea, shortness of breath, slurred speech, vomiting, general weakness. Symptoms gipermagniemii, ranked in order of increasing concentration of magnesium ions in the blood serum: reduction of deep tendon reflexes (2-3.5 mmol / L), the elongation and expansion of PQ interval QRS complex in the electrocardiogram (2.5-5 mmol / l), reduction of tendon reflexes (4-5 mmol / l), depression of the respiratory center (5-6.5 mmol / l), cardiac conduction (7.5 mmol / l), cardiac arrest (12.5 mmol / l).
Overdose Symptoms: . Disappearance of the patellar reflex, nausea, vomiting, a sharp decrease in blood pressure, bradycardia, and CNS depression drsaniya Treatment: should be in / in slowly introduce the solution of calcium chloride or calcium gluconate – 5.10 ml of 10%, carried oxygen therapy, inhalation of carbogen, artificial respiration, peritoneal dialysis or hemodialysis, symptomatic therapy.
Interaction with other medicines
Patients who together with magnesium sulfate is used and other drugs should inform your doctor.
Do effect of other drugs which depress the central nervous system.
Cardiac glycosides increase the risk of conduction disorders and atrioventricular block (especially while on / in calcium salts).
muscle relaxants and nifedipine enhance neuromuscular blockade.
In a joint application of magnesium sulfate for parenteral administration with other vasodilators may increase the hypotensive effect.
barbiturates, narcotic analgesics, antihypertensive drugs increase the likelihood of depression of the respiratory center.
interfere with the absorption of antibiotics tetracycline, reduces the effect of streptomycin and tobramycin. Calcium magnesium sulphate reducing action.
Pharmaceutically compatible (flocculates), calcium preparations, carbonates, bicarbonates and phosphates of alkali metals, clindamycin phosphate, hydrocortisone sodium succinate, polymyxin B sulfate, procaine hydrochloride, salicylates and tartrates. Magnesium ions at concentrations above 10 mg / ml in mixtures for total parenteral nutrition is a separation of fat emulsions.
Please note that \ m injections are extremely painful and lead to the formation of infiltrates.
Magnesium sulfate should be used cautiously so as not there was a toxic concentration of the drug. Elderly usually reduced dose should be used, because they have reduced kidney function. Patients with impaired renal function (creatinine clearance if more than 20 ml / min) and oliguria should not receive more than 20 g of magnesium sulfate (81 mM Mg 2+ ) for 48 hours, should not be administered magnesium sulfate / v too fast. It is recommended to control the concentration of magnesium ions in the blood serum (to be not higher than 0.8-1.2 mmol / l), urine output (at least 100 ml / h), respiratory rate (b not less than 1 / min) BP.
When administered magnesium sulphate must be prepared for on / in a solution of calcium, for example, 10% calcium gluconate solution. If necessary, at the same time / in the introduction of magnesium and calcium, are administered to different vein. When andriol using magnesium sulfate may be distorted results of radiological studies, which used technetium.