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

Pharmacodynamics:Hormonal agent, oligopeptide analogue of the hormone of the posterior lobe of the pituitary gland. Has uterotonizing, stimulating labor and lactotropic action.It has a stimulating effect on the smooth muscles of the uterus, increases the contractile activity of the myometrium and to a lesser degree the tone (especially at the end of pregnancy, during labor and immediately during delivery). Under the influence of oxytocin, the permeability of cell membranes for calcium ions increases, the resting potential decreases and their excitability increases (reduction of the membrane potential leads to an increase in the frequency, intensity, and duration of contractions). In small doses oxytocin increases the frequency and amplitude of uterine contractions, in large doses or with repeated administration contributes to an increase in the tone of the uterus, the increase and intensification of its contractions (up to the tetanic).

Stimulates the secretion of breast milk, increasing the production of prolactin in the anterior pituitary gland. Reduces myoepithelial cells around the alveoli of the breast, stimulates the flow of milk into large ducts or sinuses, contributing to increased separation of milk.

Virtually devoid of vasoconstrictor and anti diuretic action (manifests them only in high doses), does not cause contraction of the muscles of the bladder and intestines.The effect occurs after 1-2 minutes with intramuscular injection, lasts 20-30 minutes; at intravenous - in 0,5-1 minutes.

Pharmacokinetics:

The half-life period is 1-6 min (decreased in late pregnancy and lactation). The connection with plasma proteins is low (30%).

Metabolised in the liver and kidneys. During pregnancy in plasma, target organs, placenta, the concentration of oxytocinase inactivating the endogenous and exogenous oxytocin. Excretion in the main kidneys unchanged.

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, postponed, pregnancy, premature discharge of amniotic fluid, management of breech delivery).

For the prevention and treatment of hypotonic uterine bleeding after abortion (including late 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).

Contraindications:

Hypersensitivity; a narrow basin (anatomical and clinical), a transverse and oblique position of the fetus, facial presentation of the fetus, premature birth, threatening rupture of the uterus, scars on the uterus (after a previous cesarean section, operations on the uterus), excessive uterine stretching, uterus after multiple births, partial placenta previa, uterine sepsis, invasive cervical cancer; hypertension of the uterus (which did not occur during labor), fetal compression, arterial hypertension, chronic renal failure.

Pregnancy and lactation:

In the first trimester of pregnancy oxytocin apply only with spontaneous or induced abortion.

When using the drug to stop uterine bleeding to breastfeeding, you can proceed only when the course of treatment with oxytocin is completed.

Dosing and Administration:

Intravenous, intramuscular.

For the initiation of labor: intramuscularly, 0.5-2 ME (0.1-0.4 ml of the preparation); if necessary, repeat the injection every 30-60 minutes.

Stimulation of labor: intravenously drip, 10 ME oxytocin per 1 liter of a 5% dextrose solution, with the development of excessive uterine contractions, slowing the infusion quickly leads to a decrease in myometrium activity.Introduction begins with 5-8 cap / min, with the subsequent increase in speed depending on the nature of labor activity, but not more than 40 cap / min. During the infusion, constant monitoring of uterine activity and fetal heart rate is necessary.

Treatment of unavoidable or incomplete abortion: intravenously drip, 10 ME (2 ml of preparation) of oxytocin per 500 ml of 5% dextrose solution at a rate of 20-40 cap / min.

For the prevention of hypotonic uterine bleeding after abortion oxytocin injected intramuscularly, 3-5 ME (0.6-1 ml) 2-3 times daily for 2-3 days, intramuscular injection 10 is permissible ME (2 ml) immediately after removal of the placenta. For the treatment of hypotonic uterine bleeding after an abortion, 5-8 ME 2-3 times a day for 3 days. If necessary, drip intravenously 10-40 ME (2-8 ml) of oxytocin dissolved in 100 ml of donor blood.

When conducting labor in the pelvic presentation: 2-5 ME (0.4-1 ml).

To enhance the contractile capacity of the uterus in cesarean section (after removal of the afterbirth) is inserted into the wall of the uterus in a dose of 3-5 ME (0.6-1 ml).

Side effects:

In parturient women:

On the part of the reproductive system, at high doses or hypersensitivity: hypertension of the uterus, spasm, tetany,uterine rupture; increased bleeding in the postpartum period as a result of oxytocin induced thrombocytopenia, afibrinogenemii and gipoprotrombinemii, sometimes hemorrhages in the pelvic organs. With careful medical supervision of childbirth, the risk of bleeding in the postpartum period is reduced.

From the side of the cardiovascular system: at high doses, arrhythmia; ventricular extrasystole; severe hypertension (in the case of vasopressor drugs); hypotension (with simultaneous use with anesthetic cyclopropane); reflex tachycardia; shock; at too fast introduction: a bradycardia, a subarachnoidal bleeding.

From the side of the digestive system: nausea, vomiting.

From the side of water-electrolyte exchange: severe hyperhydration with prolonged intravenous administration (usually at 40-50 pm / min) with a large amount of fluid (antidiuretic effect of oxytocin), which occurs with convulsions and coma is possible with a 24-hour, slow infusion of oxytocin; rare - lethal outcome.

From the immune system: anaphylaxis and other allergic reactions, with too rapid introduction - bronchospasm; rare - lethal outcome.

In a fetus or newborn:

As a consequence of the administration of oxytocin to the mother - within 5 minutes a low score on the Apgar scale, jaundice of newborns, with too rapid introduction - a decrease in fibrinogen in the fetal blood, bleeding in the retina of the eye; as a result of increased contractile activity of the uterus - sinus bradycardia, tachycardia, ventricular extrasystole and other arrhythmias, residual changes in the central nervous system, fetal death as a result of asphyxia.

Overdose:

Symptoms: fetal compression, fetal asphyxia, fetal bradycardia, postpartum hemorrhage, tetanus of the uterus, uterine rupture, utero-placental hypoperfusion, hypoxia, hypercapnia, fetal death, fetal birth injuries, water intoxication; convulsions.

Treatment: drug cancellation, reduction of fluid administration, forced diuresis; hypertonic sodium chloride solution, normalization of electrolyte balance, barbiturates (with caution), careful observation.

Interaction:

Oxytocin enhances the pressor effect of sympathomimetics.

In combination with monoamine oxidase inhibitors, the risk of increasing blood pressure increases.

Halothane and cyclopropane increase the risk of developing arterial hypotension.

Special instructions:

Apply only under the supervision of a doctor in a hospital under the control of the contractile activity of the uterus, the condition of the fetus, blood pressure and the general condition of the woman.

Effect on the ability to drive transp. cf. and fur:

Oxytocin does not affect the ability to drive a car and mechanisms that are associated with an increased risk of injury.

Form release / dosage:

Solution for intravenous and intramuscular injection, 5 IU / ml.

Packaging:

1 ml per ampoule of neutral glass.

For 10 ampoules, together with the instruction for use and the ampoule opening opener or ampoule scarifier, is placed in a cardboard box.

5 ampoules per circuit cell packaging made of polyvinylchloride film and aluminum foil printed lacquered, or without foil.

1 or 2 contour squares, together with the instruction for use and a knife for opening ampoules or a scarifier ampullum, are placed in a pack of cardboard.

When using ampoules with break points or rings, the ampoule opener or ampoule scaper is not inserted.

Storage conditions:

In the dark place at a temperature of 8 to 15 ° C.

Keep out of the reach of children.

Shelf life:

2 years.

Do not use after the expiration date.

Terms of leave from pharmacies:On prescription

Registration number:P N002084 / 01-2003

Date of registration:05.02.2009 / 18.05.2012

Expiration Date:Unlimited

The owner of the registration certificate:DALHIMFARM, OJSC DALHIMFARM, OJSC Russia

Manufacturer: & nbsp

DALHIMFARM, OJSC Russia

Representation: & nbspDALHIMFARM, OJSCDALHIMFARM, OJSC

Information update date: & nbsp25.05.2017

Illustrated instructions

Instructions

Oxytocin (Oxytocinum)