Oxytocin during childbirth as stimulation: what kind of drug and the consequences of its use. Oxytocin injections: instructions for use How long does it take for oxytocin to leave the body?

To stimulate contractions and artificially induce labor, obstetricians often use Oxytocin. After the baby is born, the drug is prescribed to contract the uterus to prevent postpartum uterine bleeding. In addition, the medicine is used as an auxiliary therapy for incomplete abortion, when the child died in the womb, but for some reason remained in the female body. Oxytocin increases the contractility of the uterus, which helps bring the fetus out.

Composition and release form

The drug Oxytocin is produced in the form of a clear, colorless solution for intramuscular or intravenous administration. According to the instructions for use, one ampoule contains 1 ml of the product, which contains the following components:

Mechanism of action of Oxytocin

The active component of the drug is an artificial analogue of the hormone oxytocin. This substance performs many functions in the body, including preparing a woman for childbirth, and after the birth of a baby, it stimulates milk production. The hormone is synthesized by the hypothalamus, one of the parts of the brain, after which it enters the pituitary gland, then into the bloodstream. From there it goes to target cells - the uterus and mammary glands, exerting the following effects on them:

• enhances the contractile activity of the smooth muscles of the uterus and the tone of the myometrium;
• in small quantities increases the amplitude and frequency of uterine contractions;
• after childbirth, it affects the production of prolactin, which is responsible for the synthesis of milk, which helps prevent hypolactation (decreased production);
• stimulates the contraction of myoepithelial cells surrounding the alveoli and ducts of the mammary gland. This helps push milk into the ducts.

In addition, the hormone has an effect on the human psyche. It causes men and women to have a favorable attitude towards other people, is involved in sexual arousal, reduces anxiety around a partner, and forms a mother’s sense of attachment to her child.

The concentration of oxytocin in a woman’s blood does not depend on the menstrual cycle, but increases significantly during orgasm. In addition, its level changes little throughout almost the entire pregnancy. Only before childbirth does it begin to rise, reaching maximum values ​​at night and decreasing during the day. During contractions, the concentration of the hormone increases significantly, reaching maximum levels when the cervix fully opens and the baby’s head appears in the pelvic area.

The drug is especially effective when administered intravenously. The instructions for use say that it begins to act 3-7 minutes after entering the bloodstream, the effect lasts about two to three hours. The active substance is distributed in the extracellular space, binds to myometrial receptors and, by increasing the intracellular calcium content, causes contractions similar to physical spontaneous childbirth.

At the same time, under the influence of the hormone, blood flow in the uterus decreases. There is a possibility that a small amount of oxytocin enters the baby's circulatory system. The medicine also affects the smooth muscles of other organs. The drug increases blood flow in the kidneys, brain vessels, coronary arteries and veins. When a large amount of an undiluted dose is administered intravenously, a temporary decrease in blood pressure is observed, which is accompanied by a reflex increase in cardiac output and tachycardia.

According to the instructions for use, oxytocin leaves the body very quickly: the half-life is 1–6 minutes. Most of the hormone is processed by the liver and kidneys. It is destroyed by the enzyme oxytocinase, the activity of which actively increases during pregnancy.

Indications for use of Oxytocin

Most doctors are of the opinion that the drug should be administered only for therapeutic purposes, avoiding acceleration of labor during a normal pregnancy. For this reason, the instructions recommend the use of the medicine in the following situations:

• stimulation of labor in the 1st or 2nd stages of labor when uterine contractility weakens or stops;
• initiating labor in later stages if there is a need for early delivery;
• the mother has arterial hypertension, severe gestosis, cardiovascular or renal diseases, diabetes mellitus, antenatal hemorrhage;
• prevention and treatment of bleeding after abortion, childbirth, cesarean section;
• acceleration of postpartum involution - return of the uterus to the state before pregnancy (relevant as complex therapy for postpartum endometritis and some other conditions);
• auxiliary treatment for incomplete or failed abortion to bring the fetus out, causing a miscarriage;
• to diagnose uteroplacental insufficiency, in which the supply of nutrients and oxygen to the baby slows down, which leads to a delay in its development (stress test with oxytocin).

Directions for use and dosage

Important: the use of the hormone is allowed only under the supervision of a doctor, in a hospital setting. The specialist administers the drug so that the rate of cervical dilatation does not differ from the rate observed during childbirth, since excessive stimulation is life-threatening. The doctor selects the dosage individually, taking into account the reaction of the pregnant woman and the fetus to the administration of the medicine.

According to the instructions, the solution should be administered only intravenously or intramuscularly. You cannot use two injection methods at the same time. To stimulate labor, an intravenous drip is prescribed. When inserting, it is very important to monitor the rate of infusion, constantly monitor the contractility of the uterus and heart rate. If the contraction is increased, the administration of the medication should be stopped immediately. The hormonal agent is administered according to the following scheme:

• First, saline solution is administered, then Oxytocin.
• To prepare a standard solution for intravenous administration, under sterile conditions, mix 5 IU of a hormonal agent with 1 liter of a non-hydrophilic solvent, and then mix thoroughly.
• The initial injection rate of the solution should not be higher than 0.5-4 mU/min. Then every 20-40 minutes. it can be increased by 1-2 mU/min until the desired contraction frequency is achieved. For accurate dosing, use an infusion pump or similar device. In late pregnancy, the rate of solution administration must be increased very carefully. In rare cases, it can reach 8-9 mU/min. For premature birth, infusion rates above 20 mU/min are allowed.

To stop uterine bleeding after childbirth, both intravenous and intramuscular administration of the drug are used. According to the instructions for use, proceed as follows:

• Intravenous administration. Prepare a solution of 10-40 units of hormone and 1 liter of non-hydrophilic solvent. To prevent uterine atony (loss of tone and contractility), 20-49 mU/min is required.
• Intramuscular administration. After separation of the placenta, inject 5 IU of solution into the muscle.

In case of incomplete abortion, when the fertilized egg detaches from the uterus, the child dies, but remains in the mother’s body, the hormonal drug is used as follows. First, 10 IU of the drug is mixed with 500 ml of saline, then administered intravenously at a rate of 20-40 drops per minute.

The drug is used to diagnose uteroplacental insufficiency. The test involves intravenous administration of the hormone. According to the instructions, you need to act like this:

• start injecting the drug at a speed of 0.5 mU/min;
• every 20 min. double the speed until an effective dose is achieved, but not more than 20 mU/min;
• When three moderate uterine contractions appear within 10 minutes (40-60 seconds each), stop administering the solution, and then begin to monitor the fetus for the appearance of late or variable decelerations (decreases in heart rate).

special instructions

When the drug is used correctly, contractions similar to normal labor begin. Too much stimulation, which occurs when the hormone is used incorrectly, can harm both the mother and the unborn baby. In addition, the instructions for use recommend taking into account the following points:

• The medicine should not be administered until the head or buttocks of the fetus appear in the pelvis.
• The use of a hormon is permissible only in hospital settings, since in medicine there have been repeated cases of death of a woman in labor due to hemorrhage and rupture of the uterus, as well as the fetus for various reasons.
• The solution cannot be quickly injected into a vein, since it can provoke acute hypotension (low blood pressure) with the development of tachycardia and hyperemia (overflow of blood vessels).
• If there is excessive sensitivity to the drug, hypertensive contractions of the uterus are possible, even with the correct dosage, under appropriate medical supervision.
• When administering the hormone, one must take into account the possibility of increased blood loss and the occurrence of afibrinogenemia (lack of fibrinogen protein in the blood, without which the blood cannot clot).
• Oxytocin in ampoules should not be used if the dead fetus is in the uterus or if there is meconium (feces of an unborn child) in the amniotic fluid. This can cause amniotic fluid embolism, which is the name given to the penetration of amniotic fluid into the mother's bloodstream.
• The drug cannot be used for a long time in case of weak labor, when the body does not respond to the introduction of an artificial hormone.
• The medicine is used with caution in severe cardiovascular diseases.

Oxytocin for abortion

Oxytocin should not be used alone to induce a miscarriage in the first trimester, as such actions can lead to serious complications, including death. Even in a clinical setting, this drug is used no earlier than the 14th week of pregnancy, giving preference to other drugs, including Mifepristone. An abortion should only be done in a clinical setting under the supervision of a specialist.

Application for animals

The hormone is used for farm and domestic animals. According to the instructions for use, it is prescribed in the following situations:

• with weak contractions;
• uterine bleeding;
• retention of placenta;
• mastitis;
• reflex agalactia (cessation of milk production).

According to the instructions, the solution is administered subcutaneously, intramuscularly, or intravenously. The dose is calculated depending on the type and weight of the animal:

Drug interactions

Simultaneous administration of the hormone with other medications may cause undesirable consequences. According to the instructions for use, the following points must be taken into account:

• administering Oxytocin with prostaglandins is not recommended, since the latter enhance the effect of the hormonal drug, which can lead to cervical injury or uterine rupture;
• the combination of oxytocin with other inducers of labor or abortion leads to increased uterine tone, rupture or cervical injury;
• severe arterial hypertension can be provoked by the introduction of the hormone 3-4 hours after vasoconstrictors (drugs that cause vasoconstriction) with caudal anesthesia;
• the introduction of Oxytocin and anesthetics such as Cyclopropam, Enflurane, Halothane, Isoflurane, unexpectedly affects the cardiovascular system, causing disruptions in its functioning;
• the combination of cyclopropane anesthesia and a hormonal drug can provoke atrioventricular rhythm and sinus bradycardia (a type of arrhythmia);
• the hormone is prescribed cautiously to women who are taking medications that prolong the QTc interval.

Side effects of Oxytocin

Caution in the use of hormonal drugs is explained by the fact that the medicine can provoke many side effects. The instructions warn that women in labor may experience the following complications:

• Allergy.
• Overhydration – excess water in the body can lead to coma. Treatment involves fluid restriction, administration of saline solution, and control of seizures with barbiturates.
• Thrombocytopenia, hypoprothrombinemia.
• Arrhythmia, tachycardia and other heart problems.
• Hypotension (low blood pressure) followed by the development of hypertension (high blood pressure).
• Nausea, vomiting.
• Hypertonicity, uterine spasms, tetanic contractions, rupture.
• Hemorrhage into the pelvic organs.
• Premature placental abruption.
• Postpartum bleeding.
• Death.

A newborn baby may experience retinal hemorrhage, asphyxia, jaundice, brain damage, and heart problems. The instructions for use warn that fetal death during birth due to asphyxia or immediately after birth cannot be ruled out for various reasons.

Overdose

An increased dose of medication or too rapid administration can cause serious complications, including coma and death. With hyperstimulation, strong or prolonged contractions occur, which causes disordered labor, leads to rupture of the body or cervix, vagina, and severe bleeding after childbirth. With prolonged administration of the drug in large doses, water intoxication may occur, accompanied by convulsions. The child may experience bradycardia, hypoxia, hypercapnia (excess carbon dioxide), and death.

Contraindications

Oxytocin should not be used in case of allergies to the active or auxiliary substances of the drug, serious problems with the cardiovascular system, fetal hypoxia before the onset of labor. A hormone is not prescribed to stimulate labor when the baby’s delivery through natural channels is impossible (improper position of the fetus, a narrow pelvis of the woman in labor, or a discrepancy between its size and the baby’s head). The instructions indicate that the drug should not be administered in the following situations:

• the umbilical cord is located near the exit from the cervix;
• there is a risk of uterine rupture;
• immature cervix;
• numerous births;
• severe stretching of the uterus;
• history of serious surgical interventions on the cervix or body of the uterus, incl. caesarean section, removal of fibroids (benign tumor) due to the risk of organ rupture;
• there are obstacles to the baby’s passage through the natural birth canal (cervical tumor);
• strong uterine contractions;
• premature birth;
• cervical cancer;
• emergency situations where emergency surgery is required
• intervention;
• Long-term use is prohibited in cases of severe toxemia (toxicosis).

Terms of sale and storage

The drug is available with a prescription, but often it is not required to be provided at the pharmacy. According to the instructions for use, the medicine should be kept in a dark place at a temperature of 2 to 8°C. Storage period is 3 years.

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Oxytocin-Richter

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Video

Release form: Liquid dosage forms. Injection.

General characteristics. Compound:

Pharmacological properties:

Indications for use:

Important! Get to know the treatment

Directions for use and dosage:

Features of application:

Side effects:

Overdose:

Storage conditions:

Store in a place protected from light at a temperature of 8°C to 15°C.

Vacation conditions:

On prescription

Package:

Trade name of the drug: OXYTOCIN

International Nonproprietary Name (INN): oxytocin

Chemical name: oxytocin

Dosage form:

Compound:

Description:
Colorless, transparent solution, practically free from mechanical inclusions.

Pharmacological properties

Pharmacotherapeutic group:

Indications
Oxytocin is intended to induce labor and stimulate labor.
Labor induction in late or close stages of pregnancy, if early delivery is necessary due to gestosis, rhesus conflict, early or premature rupture of fetal membranes and discharge of amniotic fluid, post-term pregnancy (more than 42 weeks), intrauterine growth retardation, intrauterine fetal death.
Stimulation of labor: with primary or secondary weakness of labor in the first or second stages of labor.
Prevention and treatment of hypotonic bleeding after childbirth and abortion, during cesarean section (after the birth of a child and separation of the placenta), to accelerate postpartum involution.
Others: as an additional therapy for incomplete or incomplete (inevitable) abortion.

Contraindications
Increased sensitivity to oxytocin; the presence of contraindications for vaginal birth (for example, presentation or prolapse of the umbilical cord, complete or partial (vasa previa) placenta previa; narrow pelvis (discrepancy between the sizes of the fetal head and the pelvis of the woman in labor); transverse and oblique position of the fetus, preventing spontaneous delivery; emergency, requiring surgical intervention situations caused by the condition of the mother or the fetus; conditions of fetal distress long before the terminal stages of pregnancy; prolonged use with uterine inertia; severe gestosis (high blood pressure, impaired renal function); , arterial hypertension, impaired renal function, facial presentation of the fetus, excessive distension of the uterus, fetal compression.
Except in special circumstances, the drug is also contraindicated in the following situations: premature birth; history of major surgery on the uterus or cervix (including cesarean section); hypertonicity of the uterus; multipod pregnancy; invasive stage of cervical carcinoma.

Pregnancy and lactation
In the first trimester of pregnancy, oxytocin is used only for spontaneous or induced abortions. Numerous data on the use of oxytocin, its chemical structure and pharmacological properties indicate that, if the instructions for use are followed, oxytocin does not affect the formation of fetal malformations.
Passes into breast milk in small quantities.
When using the drug to stop uterine bleeding, breastfeeding can be started only after completing the course of treatment with oxytocin.

Directions for use and doses
Intravenously or intramuscularly.
With the chain of induction and enhancement of labor, oxytocin is used exclusively intravenously, in a hospital setting, with appropriate medical supervision. Simultaneous use of the drug intravenously and intramuscularly is contraindicated. The dose is selected taking into account the individual sensitivity of the pregnant woman and the fetus.
To induce labor and stimulate labor, oxytocin is used exclusively in the form of an intravenous drip infusion. Strict control of the prescribed infusion rate is mandatory. The safe use of oxytocin during induction and enhancement of labor requires the use of an infusion pump or other similar device, as well as monitoring of the strength of uterine contractions and fetal cardiac activity. In case of excessive increase in contractile activity of the uterus, the infusion should be stopped immediately, as a result of which the excessive muscular activity of the uterus quickly decreases.
1) Before you start administering the drug, you should start administering a saline solution that does not contain oxytocin.
2) To prepare a standard oxytocin infusion, dissolve 1 ml (5 IU) of oxytocin in 1000 ml of non-hydrating fluid and mix thoroughly by rotating the bottle. 1 ml of infusion prepared in this way contains 5 mIU of oxytocin. For precise dosing of the infusion solution, an infusion pump or other similar device should be used.
3) The rate of administration of the initial dose should not exceed 0.5-4 milliunits per minute (mU/min) (corresponds to 2-16 drops/min, since 1 drop of infusion contains 0.25 mU of oxytocin). Every 20-40 minutes it can be increased by 1-2 mIU/min until the desired degree of uterine contractility is achieved. Once the desired frequency of uterine contractions has been achieved, corresponding to spontaneous labor, and the uterine os is dilated to 4-6 cm, in the absence of signs of fetal distress, the infusion rate can be gradually reduced at a rate similar to its acceleration.
In late pregnancy, infusion at a higher rate requires caution; only in rare cases may a rate exceeding 8-9 mU/min be required. In case of premature birth, a higher speed may be required, which in isolated cases may exceed 20 mU/min (80 drops/min).
1) The fetal heartbeat, the tone of the uterus at rest, the frequency, duration and strength of its contractions should be monitored.
2) In case of uterine hyperactivity or fetal distress, oxytocin should be stopped immediately and oxygen therapy should be provided to the parturient. The condition of the mother and fetus should be re-monitored by a medical specialist.
Prevention and treatment of hypotonic bleeding in the postpartum period:
1) Intravenous drip infusion: dissolve 10-40 IU of oxytocin in 1000 ml of non-hydrating liquid; to prevent uterine atony, 20-40 IU/min of oxytocin is usually necessary.
2) Intramuscular administration: 5 IU/ml oxytocin after separation of the placenta.
Incomplete or failed abortion:
Add 10 IU/ml of oxytocin to 500 ml of saline solution or a mixture of 5% dextrose with saline solution. The intravenous infusion rate is 20-40 drops/min.

Side effect
For women in labor:
From the reproductive system: with large doses or hypersensitivity - uterine hypertension, spasm, tetany, uterine rupture, increased bleeding in the postpartum period as a result of oxytocin-induced thrombocytopenia, afibrinogenemia and hypoprothrombinemia, sometimes hemorrhage in the pelvic organs. With careful medical monitoring during labor, the risk of bleeding in the postpartum period is reduced.
From the cardiovascular system: at high doses – arrhythmia; ventricular extrasystole; severe hypertension (in the case of using vasopressor drugs); hypotension (when used simultaneously with the anesthetic cyclopropane); reflex tachycardia; shock; if administered too quickly: bradycardia, subarachnoid bleeding.
From the digestive system: nausea, vomiting.
From the side of water-electrolyte metabolism: severe overhydration with prolonged intravenous administration (usually at 40-50 mU/min) with large amounts of fluid (antidiuretic effect of oxytocin), occurring with convulsions and coma is possible with a 24-hour, slow infusion of oxytocin; rarely – death.
From the immune system: anaphylaxis and other allergic reactions, with too rapid administration bronchospasm; rarely – death
In the fetus or newborn:
As a consequence of the administration of oxytocin to the mother - within 5 minutes a low Apgar score, jaundice of newborns, with too rapid administration - a decrease in fibrinogen in the fetal blood, hemorrhage in the retina; 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 depend mainly on the degree of uterine hyperactivity, regardless of the presence of hypersensitivity to the drug. Hyperstimulation with hypertonic and tetanic contractions or with a baseline tone of ≥15-20 mm aq. Art. between two contractions leads to erratic labor, rupture of the body or cervix, vagina, bleeding in the postpartum period, uteroplacental insufficiency, fetal bradycardia, hypoxia, hypercapnia, compression, birth injuries or death. Overhydration with convulsions as a result of the antidiuretic effect of oxytocin is a serious complication and develops with prolonged administration of large doses (40-50 ml/min).
Treatment of overhydration: withdrawal of oxytocin, restriction of fluid intake, use of diuretics to increase diuresis, intravenous administration of hypertonic saline, correction of electrolyte imbalances, control of seizures with appropriate doses of barbiturates, and provision of professional care for the patient in a coma.

Drug interactions
When oxytocin is administered 3-4 hours after the use of vasoconstrictors together with caudal anesthesia, severe arterial hypertension is possible.
During anesthesia with cyclopropane and halothane, the cardiovascular effect of oxytocin may change with the unexpected development of arterial hypotension, sinus bradycardia and atrioventricular rhythm in a woman in labor during anesthesia.

special instructions
Before starting to use oxytocin, the expected beneficial effect of therapy should be compared with the possibility, although rare, of the development of hypertension and uterine tetany.
Until the fetal head is inserted into the pelvic inlet, oxytocin cannot be used to induce labor.
Every patient receiving intravenous oxytocin should be hospitalized under the constant supervision of experienced professionals who are familiar with the drug and recognized as skilled in recognizing complications. Immediate, if necessary, assistance from a medical specialist must be provided. During use of the drug, uterine contractions, cardiac activity of the mother and fetus, and blood pressure of the woman in labor should be constantly monitored to avoid complications. If there are signs of uterine hyperactivity, oxytocin should be discontinued immediately; As a result, uterine contractions caused by the drug usually subside soon.
When used adequately, oxytocin causes uterine contractions similar to spontaneous labor. Excessive stimulation of the uterus if the drug is used incorrectly is dangerous for both the mother and the fetus. Even with adequate use of the drug and appropriate monitoring, hypertensive uterine contractions occur with increased sensitivity of the uterus to oxytocin.
The risk of developing afibrinogenemia and increased blood loss should be taken into account.
There are cases of death of a woman in labor as a result of hypersensitivity reactions, subarachnoid hemorrhage, uterine rupture and fetal death for various reasons associated with parenteral administration of the drug for induction of labor and stimulation in the first and second stages of labor.
As a result of the antidiuretic effect of oxytocin, overhydration may develop, especially when using a constant infusion of oxytocin and ingesting liquids.
The drug can be diluted in solutions of sodium lactate, sodium chlorate and glucose. The prepared solution should be used within the first 8 hours after preparation. Compatibility studies were carried out with 500 ml infusions.
Effect of the drug on the ability to drive a car and machinery, work on which is associated with an increased risk of injury: oxytocin does not affect the ability to drive a car and machinery, work on which is associated with an increased risk of injury.

Release form
1 ml solution for injection in a glass ampoule, 5 ampoules in a cardboard box with instructions for medical use.

Best before date
3 years.
Do not use the drug after the expiration date indicated on the package.

Storage conditions
Store at a temperature of 2-15 °C, protected from light, out of the reach of children.

Conditions for dispensing from pharmacies
On prescription.

Manufacturer
Gedeon Richter A.O.
1103 Budapest, st. Diemrei, 19-21, Hungary Moscow Representative Office: st. Krasnaya Presnya, 1-7.

A drug that increases the tone and contractile activity of the myometrium

Active substance

Oxytocin

Release form, composition and packaging

Solution for infusion and intramuscular administration colorless, transparent.

Excipients: glacial acetic acid - 2.0 mg, chlorobutanol hemihydrate - 3 mg, ethanol 96% - 40 mg, water for injection - up to 1 ml.

1 ml - glass ampoules (5) - contour plastic packaging (1) - cardboard packs.

pharmachologic effect

Synthetic hormonal drug. Its pharmacological and clinical properties are similar to endogenous oxytocin of the posterior pituitary gland. Interacts with oxytocin-specific receptors of the uterine myometrium, belonging to the G-protein superfamily. The number of receptors and the response to the action of oxytocin increase as pregnancy progresses and reach a maximum towards the end of it. Stimulates labor activity of the uterus by increasing the permeability of cell membranes to calcium ions and increasing its intracellular concentration, subsequently reducing the resting potential of the membrane and increasing its excitability. Causes contractions similar to normal spontaneous labor, temporarily reducing the blood supply to the uterus. With an increase in the amplitude and duration of muscle contractions, the cervix of the uterus expands and smoothes. In appropriate quantities, it can enhance the contractility of the uterus from moderate in strength and frequency, characteristic of spontaneous motor activity, to the level of prolonged tetanic contractions.

Causes contraction of myoepithelial cells adjacent to the alveoli of the mammary gland, improving the secretion of breast milk.

By acting on vascular smooth muscle, it causes vasodilation and increases blood flow in the kidneys, coronary vessels and cerebral vessels. Typically, blood pressure remains unchanged, but with intravenous administration of high doses or a concentrated solution of oxytocin, blood pressure may temporarily decrease with the development of reflex tachycardia and a reflex increase in output. Following the initial decrease in blood pressure, there is a prolonged, albeit small increase.

Unlike vasopressin, oxytocin has minimal antidiuretic effect, but overhydration is possible when oxytocin is administered with large quantities of electrolyte-free solutions and/or when they are administered too quickly. Does not cause contraction of the muscles of the bladder and intestines.

Pharmacokinetics

With intravenous administration, the effect of oxytocin on the uterus appears almost instantly and lasts for 1 hour. With intramuscular administration, the myotonic effect occurs in the first 3-7 minutes and lasts for 2-3 hours.

Like vasopressin, oxytocin is distributed throughout the extracellular space. Small amounts of oxytocin appear to enter the fetal circulation. T1/2 is 1-6 minutes and becomes shorter in late pregnancy and lactation. Most of the drug is rapidly metabolized in the liver and kidneys. During the process of enzymatic hydrolysis, it is inactivated, primarily under the action of tissue oxytokinase (oxytokinase is also found in the placenta and). Only a small amount of oxytocin is excreted unchanged by the kidneys.

Indications

- for induction of labor and stimulation of labor (primary and secondary weakness of labor; the need for early delivery due to gestosis, Rh conflict, intrauterine fetal death; post-term pregnancy; premature rupture of amniotic fluid, management of labor in breech presentation);

- for the prevention and treatment of hypotonic uterine bleeding after abortion (including during long periods of pregnancy);

- in the early postpartum period to accelerate postpartum involution of the uterus;

- for contraction of the uterus during caesarean section (after removal of the placenta).

Contraindications

— narrow pelvis (anatomical and clinical);

- transverse or oblique position of the fetus;

- facial presentation of the fetus;

- premature birth;

- threatening uterine rupture;

— scars on the uterus (after a previous cesarean section, operations on the uterus);

- excessive stretching of the uterus;

- uterus after multiple births;

— partial placenta previa;

- uterine sepsis;

- invasive cervical carcinoma;

- hypertonicity of the uterus (not arising during childbirth);

— chronic renal failure;

- hypersensitivity to the components of the drug.

Dosage

IV or IM.

For the purpose of induction and enhancement of labor, oxytocin is used exclusively intravenously in the form of infusion, in a hospital setting, under appropriate medical supervision. Simultaneous use of the drug intravenously and intramuscularly is contraindicated. The dose is selected taking into account the individual sensitivity of the pregnant woman and the fetus.

For induction of labor and stimulation of labor Oxytocin is used exclusively as an intravenous drip infusion. Strict control of the prescribed infusion rate is mandatory. To safely use oxytocin during induction and enhancement of labor, it is necessary to use an infusion pump or other similar device, as well as monitor the strength of uterine contractions and fetal cardiac activity. In case of excessive increase in contractile activity of the uterus, the infusion should be stopped immediately, as a result of which the excessive muscular activity of the uterus quickly decreases.

1. Before you begin administering the drug, you should begin administering saline solution that does not contain oxytocin.

2. To prepare a standard oxytocin infusion, dissolve 1 ml (5 IU) of oxytocin in 1000 ml of non-hydrating liquid and mix thoroughly, rotating the bottle. 1 ml of infusion prepared in this way contains 5 mIU of oxytocin. For precise dosing of the infusion solution, an infusion pump or other similar device should be used.

3. The rate of administration of the initial dose should not exceed 0.5-4 mIU/min, which corresponds to 2-16 drops/min, because 1 drop of infusion contains 0.25 mIU of oxytocin). Every 20-40 minutes it can be increased by 1-2 mIU/min until the desired degree of uterine contractility is achieved. Once the desired frequency of uterine contractions has been achieved, corresponding to spontaneous labor, and the uterine os is dilated to 4-6 cm in the absence of signs of fetal distress, the infusion rate can be gradually reduced at a rate similar to its acceleration.

In late pregnancy, infusion at a higher rate requires caution; only in rare cases may a rate exceeding 8-9 mU/min be required. In case of premature birth, a higher speed may be required, which in isolated cases may exceed 20 mU/min (80 drops/min).

1. The fetal heartbeat, the tone of the uterus at rest, the frequency, duration and strength of its contractions should be monitored.

2. In the event of uterine hyperactivity or fetal distress, oxytocin should be stopped immediately and oxygen therapy should be provided to the parturient. The condition of the mother and fetus should be re-monitored by a medical specialist.

Prevention and treatment of hypotonic bleeding in the postpartum period

1. IV drip infusion: dissolve 10-40 IU of oxytocin in 1000 ml of non-hydrating liquid; To prevent uterine atony, 20-40 mIU/min of oxytocin is usually needed.

2. IM administration: 5 IU/ml oxytocin after separation of the placenta.

Incomplete or failed abortion

Add 10 IU/ml of oxytocin to 500 ml of saline solution or a mixture of 5% with saline solution. The rate of IV infusion is 20-40 drops/min.

Side effects

In women giving birth

From the reproductive system: with large doses or increased sensitivity - uterine hypertonicity, spasm, tetany, uterine rupture; increased bleeding in the postpartum period as a result of oxytocin-induced thrombocytopenia, afibrinogenemia and hypoprothrombinemia, sometimes hemorrhage in the pelvic organs. With careful medical monitoring during labor, the risk of postpartum bleeding is reduced.

From the cardiovascular system: when used in high doses - arrhythmia, ventricular extrasystole, severe arterial hypertension (in the case of using vasopressor drugs), arterial hypotension (when used simultaneously with the anesthetic cyclopropane), reflex tachycardia, shock, if administered too quickly - bradycardia, subarachnoid hemorrhage.

From the digestive system: nausea, vomiting.

From the side of water-electrolyte metabolism: severe overhydration with prolonged intravenous administration (usually at a rate of 40-50 mU/min) with large amounts of fluid (antidiuretic effect of oxytocin), can also occur with a 24-hour slow infusion of oxytocin, accompanied by convulsions and coma; rarely - death.

Allergic reactions: anaphylaxis and other allergic reactions, with too rapid administration bronchospasm; rarely - death.

In the fetus or newborn

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

Overdose

Symptoms depend mainly on the degree of hyperactivity of the uterus, regardless of the presence of hypersensitivity to the drug. Hyperstimulation with hypertonic and tetanic contractions or with basal tone ≥15-20 mm aq. Art. between two contractions leads to incoordination of labor, rupture of the body or cervix, vagina, bleeding in the postpartum period, uteroplacental insufficiency, fetal bradycardia, hypoxia, hypercapnia, compression, or death. Overhydration with convulsions as a result of the antidiuretic effect of oxytocin is a serious complication and develops with prolonged administration of the drug in high doses (40-50 ml/min).

Treatment overhydration: withdrawal of oxytocin, restriction of fluid intake, use of diuretics to force diuresis, intravenous administration of hypertonic saline, correction of electrolyte imbalance, control of seizures with appropriate doses of barbiturates and ensuring careful care of the patient in a coma.

Drug interactions

When oxytocin is administered 3-4 hours after the use of vasoconstrictors together with caudal anesthesia, severe arterial hypertension is possible.

During anesthesia with cyclopropane, the cardiovascular effect of oxytocin may change with the unexpected development of arterial hypotension, sinus bradycardia and AV rhythm in a woman in labor during anesthesia.

special instructions

Until the fetal head is inserted into the pelvic inlet, oxytocin cannot be used to stimulate labor.

Before starting to use oxytocin, the expected benefit of therapy should be weighed against the possibility, albeit small, of developing hypertension and uterine tetany.

Each patient receiving oxytocin IV by infusion should be in the hospital under constant supervision by experienced specialists experienced in using the drug and recognizing complications. If necessary, immediate assistance from a medical specialist must be provided. To avoid complications during the use of the drug, uterine contractions, cardiac activity of the mother and fetus, and blood pressure of the mother should be constantly monitored. If there are signs of uterine hyperactivity, oxytocin administration should be stopped immediately, as a result of which uterine contractions caused by the drug usually subside soon.

When used adequately, oxytocin causes uterine contractions similar to spontaneous labor. Excessive stimulation of the uterus if the drug is used incorrectly is dangerous for both the mother and the fetus. Even with adequate use of the drug and appropriate monitoring, hypertensive uterine contractions occur with increased sensitivity of the uterus to oxytocin.

The risk of developing afibrinogenemia and increased blood loss should be taken into account.

There are cases of death of a woman in labor as a result of hypersensitivity reactions, subarachnoid hemorrhage, uterine rupture and fetal death for various reasons associated with parenteral administration of the drug for induction of labor and stimulation of labor in the first and second stages of labor.

As a result of the antidiuretic effect of oxytocin, overhydration may develop, especially when using a constant infusion of oxytocin and ingesting fluids.

The drug can be diluted in solutions of sodium lactate and glucose. The prepared solution should be used within the first 8 hours after its preparation. Compatibility studies were carried out with 500 ml infusions.

Impact on the ability to drive vehicles and machinery

Oxytocin does not affect the ability to drive a car or operate machinery, the operation of which is associated with an increased risk of injury.

Pregnancy and lactation

In the first trimester of pregnancy, oxytocin is used only for spontaneous or induced abortions. Numerous data on the use of oxytocin, its chemical structure and pharmacological properties indicate that, if the recommendations are followed, the likelihood of oxytocin influencing an increase in the incidence of fetal malformations is small.

Excreted in small quantities into breast milk.

When using the drug to stop uterine bleeding, breastfeeding can be started only after completing the course of treatment with oxytocin.

For impaired renal function

Use is contraindicated in chronic renal failure.

Conditions for dispensing from pharmacies

The drug is available with a prescription.

Storage conditions and periods

The drug should be stored out of the reach of children, protected from light at a temperature of 2° to 15°C. Shelf life - 3 years. Do not use the drug after the expiration date.

Oxytocin is a synthetic hormonal agent with clinical and pharmacological properties similar to endogenous oxytocin of the posterior pituitary gland; labor stimulant.

Release form and composition

• Solution for injection (1 ml in ampoules, 10 ampoules in contour plastic packages, 1 package in a cardboard pack);
• Solution for injection and topical use (1 ml in glass ampoules: 10 ampoules in contour plastic packages, 1 or 2 packages in a cardboard pack; 5 ampoules in contour plastic packages, 2 packages in a cardboard pack);
• Solution for intravenous and intramuscular administration (1 ml in ampoules: 5 or 10 ampoules in cardboard packs; 5 ampoules in blister plastic packages, 1 or 2 packages in a cardboard pack; 10 ampoules in blister packs, 1 package in a pack cardboard).

Solution: transparent, colorless, practically free from mechanical inclusions.

Active ingredient: oxytocin, 1 ml – 5 IU.

Excipients: acetic acid, water for injection, chlorobutanol hemihydrate.

Indications for use

• Induction of labor in late or close stages of pregnancy, if early delivery is necessary due to post-term pregnancy (more than 42 weeks), Rh conflict, gestosis, premature or early rupture of fetal membranes and discharge of amniotic fluid, intrauterine growth restriction or fetal death;
• Stimulation of labor in case of primary or secondary weakness in the first or second stage of labor;
• Treatment and prevention of hypotonic bleeding after abortion or childbirth, during cesarean section (after the birth of a child and separation of the placenta);
• Acceleration of postpartum involution;
• Lactostasis in the early postpartum period;
• Painful premenstrual syndrome, accompanied by swelling and weight gain.

Oxytocin is used as an adjuvant for incomplete or incomplete abortion.

Contraindications

Absolute:

• The presence of contraindications for vaginal birth (for example, partial or complete placenta previa, umbilical cord presentation or prolapse, narrow pelvis (discrepancy between the sizes of the woman’s pelvis and the fetal head);
• Oblique or transverse position of the fetus, preventing spontaneous delivery;
• Emergency situations caused by the condition of the fetus and/or the woman in labor requiring surgical intervention;
• Severe gestosis (high blood pressure, impaired renal function);
• Long-term use for uterine inertia;
• States of fetal distress long before the terminal stages of pregnancy;
• Hypertonicity of the uterus that did not arise during childbirth;
• Fetal compression;
• Excessive distension of the uterus;
• Facial presentation of the fetus;
• Uterine sepsis;
• Arterial hypertension;
• Heart diseases;
• Renal dysfunction;
• Hypersensitivity to the drug.

Except in special circumstances, Oxytocin is also contraindicated in the following situations:

• Multiple pregnancy;
• Hypertonicity of the uterus;
• Premature birth;
• History of major surgery on the uterus or cervix (including cesarean section);
• Invasive stage of cervical carcinoma.

Directions for use and dosage

Oxytocin is administered intravenously (drip), intramuscularly, into the vaginal part of the cervix or the wall of the uterus, and is also used intranasally.

To induce and enhance labor, the drug is administered intravenously in a hospital, under appropriate medical supervision. The dose is selected by the doctor individually, taking into account the sensitivity of the pregnant woman and the fetus.

To induce labor and stimulate labor, the drug is administered as a drip intravenous infusion under strict control of the rate of solution administration. For safe use, use an infusion pump or other similar device, and be sure to monitor the strength of uterine contractions and fetal cardiac activity. In case of excessive increase in contractile activity of the uterus, the infusion is immediately stopped, as a result, the muscular activity of the uterus quickly decreases.

Rules for administering the drug:

• A saline solution that does not contain oxytocin is pre-injected;
• Prepare an infusion: 1 ml (5 IU) of oxytocin is dissolved in 1000 ml of non-hydrating liquid and mixed thoroughly by rotating the bottle;
• The drug is administered at an initial rate of no more than 0.5-4 milliunits/minute (mU/min; which corresponds to 2-16 drops/minute). Every 20-40 minutes, if necessary, the speed is increased by 1-2 mU/minute until the desired degree of uterine contractility is achieved. After achieving the desired frequency of uterine contractions, corresponding to spontaneous labor, and dilation of the uterine throat to 4-6 cm in the absence of signs of fetal distress, the infusion rate is gradually reduced at the same pace at which it was increased.

Caution should be exercised when administering oxytocin at high rates during late pregnancy. A rate of more than 8-9 mU/minute may be required in exceptional cases.

In case of premature birth, it may be necessary to administer the drug at a high rate; in isolated cases it may exceed 20 mIU/minute (80 drops/minute).

During the administration of Oxytocin, the tone of the uterus at rest, the fetal heartbeat, the frequency, strength and duration of uterine contractions should be monitored. In the event of fetal distress or uterine hyperactivity, the drug should be stopped immediately and oxygen therapy should be provided to the parturient.

And although intravenous administration is more preferable, intramuscular administration of the drug is possible to induce labor and stimulate labor. In the first case - 1 IU every 30-60 minutes, in the second case - 0.5-1 IU every 30-60 minutes.

Treatment and prevention of hypotonic bleeding in the postpartum period:

• Intravenous drip: 10-40 IU in 1000 ml of non-hydrating fluid; for the prevention of uterine atony, 20-40 IU/minute is usually required;
• Intramuscular: 5 IU/ml after separation of the placenta.

In case of incomplete or failed abortion, Oxytocin is prescribed at a dose of 10 IU/ml in 500 ml of saline solution or a mixture of saline solution and 5% dextrose solution. Administer intravenously at a rate of 20-40 drops/minute.

To stimulate lactation, the drug is administered intramuscularly or used intranasally (using a pipette) - 0.5 IU 5 minutes before feeding. If necessary, administration/instillation is repeated.

For premenstrual syndrome, Oxytocin is used intranasally, from the 20th day of the cycle to the 1st day of menstruation.

Side effects

For women in labor:

• Reproductive system: in case of hypersensitivity or use of high doses - spasm, uterine hypertension, uterine rupture, tetany, increased bleeding in the postpartum period as a result of oxytocin-induced hypoprothrombinemia, afibrinogenemia or thrombocytopenia, sometimes hemorrhage in the pelvic organs (with careful medical monitoring during childbirth, the risk bleeding decreases);
• Cardiovascular system: when using high doses - arrhythmia, ventricular extrasystole, reflex tachycardia, hypotension (in the case of simultaneous use of the anesthetic cyclopropane), severe hypertension (in the case of simultaneous use of vasopressor drugs), shock; if administered too quickly - subarachnoid bleeding, bradycardia;
• Digestive system: nausea, vomiting;
• Water-electrolyte metabolism: severe overhydration with prolonged intravenous administration (usually 40-50 mIU/minute) with large amounts of fluid, occurring with convulsions and coma, possible with a slow 24-hour infusion of oxytocin; rarely – death;
• Immune system: allergic reactions, including anaphylaxis; if administered too quickly - bronchospasm, in some cases - death.

In the fetus and newborn (due to the administration of oxytocin to the mother):

• Within 5 minutes after birth, low Apgar score, neonatal jaundice;
• If the drug is administered to the mother too quickly: hemorrhage in the retina, decreased fibrinogen in the blood;
• Side effects caused by increased contractile activity of the uterus: tachycardia, sinus bradycardia, ventricular extrasystole and other arrhythmias, changes in the central nervous system, fetal death due to asphyxia.

special instructions

Oxytocin is used only after comparing the expected beneficial effect with the risk, albeit rare, of developing uterine tetany and hypertension.

Oxytocin should not be used to induce labor until the fetal head is inserted into the pelvic inlet.

The drug should be administered only in a hospital setting under the constant supervision of qualified specialists who have experience working with the drug and are able to recognize complications. During the use of oxytocin, it is necessary to constantly monitor the uterine contractions and blood pressure of the woman in labor, as well as the cardiac activity of the woman in labor and the fetus. If signs of uterine hyperactivity appear, administration of the drug should be stopped immediately.

When used adequately, Oxytocin causes uterine contractions similar to those during spontaneous labor. Excessive stimulation of the uterus if the drug is used incorrectly is dangerous for the fetus and the woman in labor.

It should be borne in mind that even with adequate use of the drug, hypertensive uterine contractions can occur with increased sensitivity of the uterus to oxytocin.

The risk of increased blood loss and the development of afibrinogenemia cannot be excluded.

When oxytocin is used for induction and stimulation of labor in the first and second stages of labor, there are known cases of death of women in labor as a result of uterine rupture, subarachnoid hemorrhage and hypersensitivity reactions, as well as fetal death from various causes.

Due to the antidiuretic effect of oxytocin, there is a possibility of developing overhydration, especially when carrying out a constant infusion of the drug and ingesting liquid.

Oxytocin can be diluted in solutions of glucose, sodium chlorate and sodium lactate. The diluted solution can be used within 8 hours. Compatibility studies were carried out with 500 ml infusions.

Oxytocin does not affect the speed of reactions and the ability to concentrate.

Drug interactions

If cyclopropane or halothane is used for anesthesia, the cardiovascular effect of oxytocin may change with the unexpected development of sinus bradycardia, arterial hypotension and atrioventricular rhythm in a woman in labor.

If oxytocin is administered 3-4 hours after the use of vasoconstrictors simultaneously with caudal anesthesia, there is a risk of developing severe arterial hypertension.

Terms and conditions of storage

Store at a temperature of 2 to 15 °C in a place protected from light, out of reach of children.

Shelf life – 3 years.

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