Oxytocin - instructions for use, dose, side effects, contraindications

It has the ability to selectively increase the tone and contractile activity of the smooth muscles of the uterus, especially towards the end of pregnancy, during labor and immediately during delivery. Affects specific receptors in myometrium and increases the intracellular content of Ca²⁺. Stimulates rhythmic contractions of the uterus - strengthens and increases their frequency.Increases the secretion of prolactin, acts on the myoepithelial elements of the mammary gland, causes a reduction in the smooth muscle of the walls of the alveoli, and stimulates the flow of milk into large ducts or sinuses, facilitates its isolation. Has pressor properties and can cause antidiuretic effect when using large doses.

Pharmacokinetics:

After parenteral administration, the half-life of the plasma is from one to several minutes. Metabolised in the liver. When pregnancy in the blood plasma, target organs, placenta appears a specific enzyme oxytocinase, inactivating endogenous and exogenous oxytocin. With parenteral administration, the elimination half-life is from one to several minutes. The drug is excreted by the kidneys unchanged.

Half-life from the plasma - about 1-6 minutes (decreases in late pregnancy and during lactation). After intravenous administration of oxytocin, the reaction of the uterus appears almost immediately, and then gradually decreases within 1 hour, after intramuscular - After 3-7 minutes and lasts 30 minutes - 3 hours. It is well and quickly absorbed into the systemic bloodstream through the nasal mucosa.Half-life - less than 10 minutes, is excreted mainly by the kidneys (only a small amount in unchanged form) and liver.

Indications:

For the initiation and stimulation of labor (primary and secondary weakness of labor, the need for early delivery in connection with gestosis, rhesus-conflict, intrauterine fetal death, a delayed pregnancy, premature discharge of amniotic fluid). For the prevention and treatment of hypotonic uterine bleeding after abortion (including for long periods of pregnancy), in the early postpartum period and to accelerate the postpartum involution of the uterus; to enhance the contractile capacity of the uterus in cesarean section (after removal of the afterbirth). Hypolactation in the postpartum period. Painful premenstrual syndrome, accompanied by edema, weight gain.

ICD-10

XIV.N80-N98.N85.3 Subinvolution of the uterus

XIV.N80-N98.N94.3 Premenstrual tension syndrome

XV.O00-O08.O03.3 Spontaneous abortion - incomplete abortion with other and unspecified complications

XV.O00-O08.O07.1 Unsuccessful medical abortion complicated by prolonged or excessive bleeding

XV.O30-O48.O48 Mature pregnancy

XV.O60-O75.O62 Violations of labor [of the clan]

XV.O60-O75.O72 Postpartum hemorrhage

XV.O60-O75.O75.8 Other specified complications of labor and delivery

XV.O80-O84.O82 Singleton births, delivery was by caesarean section

XV.O85-O92.O92.7 Other and unspecified disorders of lactation

XVI.P90-P96.P95 Fetal death for unspecified cause

Contraindications:

Hypersensitivity.
Arterial hypertension.
Chronic renal failure.
Hypertensive contractions of the uterus.
Conditions with a predisposition to rupture of the uterus (including traumatic births and cesarean section operations in the anamnesis).
Threatening rupture of the uterus.
The presence of a scar after a cesarean section.
The transverse or oblique position of the fetus.
The mismatch between the size of the fetus and the pelvis of the woman in childbirth (narrow pelvis).
Premature birth.
Hypertension of the uterus (which did not occur during childbirth).
Excessive stretching of the uterus.
Fetal compression.
Uterine sepsis.
Intrauterine hypoxia of the fetus.
Invasive carcinoma of the cervix.
Uterus after multiple births.
Placenta previa.
Suspicion of premature detachment of the placenta.

Carefully:

No data.

Pregnancy and lactation:

Category FDA - X. Showed in I trimester of pregnancy with incomplete abortion or artificial termination of pregnancy. Not recommended during pregnancy, because it can cause miscarriage. It penetrates into breast milk in small amounts. When applied to stimulate the release of milk, a negative effect on the child is not described.

Dosing and Administration:

Dosing regimen is individual.

Intramuscularly, intravenously (slow). 1-3 IU; at cesarean section - 5 IU; with atonic bleeding intramuscularly or subcutaneously - 5-10 IU.

Side effects:

From the digestive system: dyspeptic phenomena, vomiting, nausea.

On the part of the endocrine system: vasopressin-like action (water retention (with prolonged intravenous administered)).

From the side of the cardiovascular system: violation of the heart rhythm, arrhythmia (including in the fetus), bradycardia (in the mother and fetus), increase HELL and subarachnoidal bleeding or depression HELL and shock.

On the part of the reproductive system: disproportionate or excessively intense labor, intrauterine fetal distress (bradycardia, arrhythmia, asphyxia), rupture of the uterus, premature placental abruption, hypertension of the uterus.

Allergic reactions: skin rashes, itching.

Other: bronchospasm; neonatal jaundice, decreased fibrinogen concentration in the fetus.

Overdose:

Symptoms: hyperstimulation of the uterus until the rupture, bleeding after delivery, utero-placental hypoperfusion, hypoxia and hypercapnia of the fetus, water intoxication (cramps are possible).

Treatment: cancellation of the drug, forced diuresis, normalization of the electrolyte balance.

Interaction:

The drug potentiates the pressor effect of sympathomimetics.
Simultaneous reception of prostaglandins potentiates the effects of the drug on the uterus.

Inhaled drugs for anesthesia potentiate the hypotensive effects of the drug, weaken its effects on the uterus.

Special instructions:

Taking the drug is only possible under the supervision of a doctor.

Impact on the ability to drive vehicles and manage mechanisms not found.

Instructions

Oxytocin (Oxytocinum)