Oxytocin - a medicine to stimulate labor and lactation

When a woman is preparing to become a mother, and the expected date of birth is about to arrive, the hypothalamus produces the hormone oxytocin, which regulates labor and lactation. It acts on the uterus, causing it to contract. The same effect is observed in the mammary gland. The myoepithelial cells surrounding the alveoli contract and, as it were, “squeeze” milk out of the ducts.

But this is a natural, natural way. It happens that obstetricians-gynecologists note weak labor activity. The uterus contracts poorly and irregularly.

Oxytocin helps the health of a woman and her child

Weakness of labor can lead to prolonged immobility of the fetus in the pelvic area of ​​the woman in labor. And this can negatively affect the health of the woman and child. In this case, synthetic Oxytocin is used, which repeats the effect of the hormone of the same name. That is, it stimulates labor and the production of prolactin. Also, Oxytocin helps retain fluid, maintaining its optimal amount; has a vasoconstrictor effect, preventing bleeding.

Oxytocin in ampoules (the name of the synthetic drug is a prescription drug produced in the form of a solution for intramuscular (IM) and intravenous (IV) administration. This is a clear, colorless liquid without mechanical inclusions, the active substance in which is the synthetic hormone oxytocin (5 IU in 1 ampoule) The auxiliary components are ethanol (96%), glacial acetic acid, chlorobutanol hemihydrate, water for injection.

Indications for use

Oxytocin is used to contract the uterus during and after childbirth strictly as directed and under the supervision of a physician. The instructions for use indicate the following cases when the drug can be prescribed:

• stimulation of labor in the first and second stages of labor with weakness (primary or secondary) labor contractions;
• induction of labor in the late or close period of pregnancy, in case of need for early birth due to intrauterine growth retardation, Rh conflict, gestosis, premature or early rupture of fetal membranes and rupture of amniotic fluid, intrauterine death of the fetus, post-term pregnancy (after 42 weeks );
• prevention and treatment of hypotonic bleeding after abortion, miscarriage, childbirth, cesarean section (after the birth of a child and separation of the placenta) (in order to accelerate postpartum involution of the uterus);
• additional therapy for failed or incomplete abortion;
• swelling, weight gain before menstruation;
• insufficient patency of the mammary gland ducts during lactation.

Oxytocin therapy includes induced labor. Cases of their occurrence:

• for late toxicosis;
• due to fetal death;
• if Rh conflict is detected;
• if the amniotic fluid has passed prematurely;
• when the pregnancy period is exceeded.

Contraindications

According to the instructions, Oxytocin is contraindicated in the following cases:

• narrow pelvis of the woman in labor (discrepancy between the sizes of the pelvis and the fetal head);
• presentation or prolapse of the umbilical cord;
• partial or complete placenta previa;
• oblique and transverse position of the fetus, interfering with spontaneous delivery;
• emergency situations requiring surgical intervention caused by the condition of the fetus or the woman in labor;
• excessive distension of the uterus;
• facial presentation of the fetus;
• fetal compression;
• uterine sepsis;
• fetal distress long before the onset of terminal pregnancy;
• severe gestosis (impaired kidney function, high blood pressure);
• hypertonicity of the uterus (appearing before childbirth);
• heart disease, arterial hypertension;
• renal dysfunction;
• breastfeeding period;
• multiple pregnancy;
• premature birth;
• previous extensive surgical intervention on the uterus and its cervix (including cesarean section);
• uterine passivity
• invasive stage of cervical carcinoma;
• hypersensitivity to oxytocin and other components of the drug.

Side effects

Like any drug, Oxytocin has unwanted reactions. If any occur during therapy, the drug is discontinued and accelerated diuresis is performed. These side effects may occur:

• Reproductive system: at high doses or hypersensitivity - uterine hypertonicity, tetany, spasm, uterine rupture, increased bleeding after childbirth (due to thrombocytopenia, hypoprothrombinemia or afibrinogenemia caused by oxytocin); sometimes – hemorrhages in the pelvic organs;
• Digestive system: nausea, vomiting, digestive tract dysfunction;

Nausea is a possible side effect of taking Oxytocin.

• Cardiovascular system (in the fetus and mother): at high doses - ventricular extrasystole, arrhythmia, severe hypertension (with the use of vasopressors), hypotension (when combined with the anesthetic cyclopropane), reflex tachycardia, shock; at a high rate of administration - subarachnoid (cerebral) bleeding, bradycardia;
• Water-electrolyte metabolism: with long-term (24 hours) slow intravenous administration, severe overhydration may occur (usually at a high infusion rate), occurring with convulsions and coma; rarely – death;
• Immune system: development of allergic reactions (including anaphylaxis); at a high rate of administration - bronchospasm; rarely – death.

Also, the use of Oxytocin can cause side effects in the fetus or newborn in the form of:

• neonatal (intrauterine) jaundice of newborns;
• low Apgar score within 5 minutes;
• at a high injection rate - hemorrhage in the retina of the eye;
• decrease in fibrinogen in fetal blood;
• with increased contractile activity of the uterus - residual changes in the central nervous system;
• arrhythmia (including tachycardia, sinus bradycardia, ventricular extrasystole);
• fetal death as a result of asphyxia.

Overdose

Take the drug strictly as prescribed by the doctor

It is very important to use Oxytocin as prescribed by your doctor and strictly as directed. This will help avoid negative consequences for both the woman and the child. Signs of a drug overdose include:

• uterine rupture;
• hypoxia;
• tetanus of the uterus;
• water intoxication;
• postpartum hemorrhage;
• hypercapnia;
• uteroplacental hypoperfusion;
• birth injuries and bradycardia in the fetus;
• convulsions.

Content

• 1 Oxytocin 1.1 Psychotropic effects
• 1.2 Treatment of anorexia
• 1.3 Oxytocin secretion

Directions for use and dosage

Instructions for use of Oxytocin involve the use of a solution for intramuscular (IM) or intravenous (IV) administration. It is prohibited to simultaneously administer the solution intramuscularly and intravenously. The dosage is calculated by the attending physician, who takes into account the individual tolerance of the drug by the woman and the fetus.

The action of Oxytocin begins 1-5 minutes after its administration and lasts approximately 3 hours.

Oxytocin intramuscularly

If after childbirth the uterus contracts poorly, the woman is prescribed injections depending on the individually calculated dose - from 2 to 10 IU.

Oxytocin intravenously

This method is used to enhance labor. The drug is administered in a hospital under the supervision of medical personnel.

It is worth noting that stimulation of the birth process cannot be carried out until the baby’s head appears.

Stimulation is carried out as follows:

• first, a saline solution that does not contain Oxytocin is injected;
• after 5 IU, Oxytocin is diluted in 1000 ml of non-hydrating liquid and the drug is administered at a rate of 2–16 drops per minute. To achieve the desired contractile activity of the uterine walls, the intensity is increased by 4–8 drops every 20–40 minutes;
• if the uterus has dilated to the required level (4-6 cm), its contractions correspond to natural labor, and no symptoms of fetal distress are observed, then the infusion rate is reduced in the reverse order.

During artificial childbirth, which takes place in late pregnancy, the rate of administration of the solution is 32–36 drops. Premature labor is an indication to increase the infusion rate to 80 drops per minute.

In this case, throughout the entire period of Oxytocin administration, it is necessary to monitor the child’s heartbeat, the tone of the uterus during contractions and at rest, as well as the frequency, strength and duration of its contractions.

Oxytocin for abortion

During an abortion, a woman is injected intravenously with a solution of 10 IU/ml of oxytocin and 500 ml of a 5% dextrose solution at a rate of 20–40 drops per minute.

Oxytocin[edit | edit code]

Healthy muscle from a young animal is shown on the left.
With age, the muscle's ability to repair declines, as shown in the middle picture (muscle fiber density decreases, scar tissue grows and inflammation occurs). On the right, a muscle of an elderly individual after treatment with oxytocin Oxytocin

(Oxytocin) is a peptide hormone of the neuropituitary gland, which is structurally similar to antidiuretic hormone (ADH). Both hormones are nonapeptides, differing in only two amino acid residues (oxytocin contains Ile3 and Leu8).

A new 2014 study published in the journal Nature Communications[1] demonstrated that oxytocin, along with its already known effects (increasing maternal instinct and social bonding), plays a key role in the repair of muscle tissue. Oxytocin is considered a high potential treatment for age-related muscle wasting. The FDA recently approved human studies of oxytocin as an anti-aging treatment.

Oxytocin, under certain circumstances, indirectly inhibits the release of adrenocorticotropic hormone and cortisol, and in some situations may also be considered a vasopressin antagonist[2].

Psychotropic effects[edit | edit code]

Oxytocin has a pronounced effect on the psycho-emotional state of men and women, which is why it is often called the “hormone of love” or “trust.” It causes a more favorable disposition towards other people, allows you to believe the words of a particular person, but only in certain cases: this applies only to intra-group relations - a person’s attitude towards people from other groups does not change either for the better or for the worse (the so-called “parochial altruism"). The hormone is involved immediately after birth in the formation of the mother-child relationship.

Treatment of anorexia[edit | edit code]

Oxytocin helps treat anorexia, according to study author Professor Janet Treasure. The article was published in the scientific journal Psychoneuroendocrinology.

Scientists have reportedly used oxytocin to treat anorexia in several girls. After two weeks of using the hormone, their aversion to food disappeared, and a month later they were virtually completely cured of anorexia.

Secretion of oxytocin[edit | edit code]

Oxytocin is produced in neurons of the paraventricular nuclei and in smaller quantities in neurons of the supraoptic nucleus. It is synthesized as a large precursor molecule, which is rapidly cleaved to form oxytocin and neurophysin I. In secretory granules, both fragments form a complex that is secreted from nerve endings located primarily in the neurohypophysis. In addition to the neurohypophysis, oxytocinergic neurons project to other areas of the hypothalamus, the brainstem and the spinal cord. They participate in the regulation of the activity of the autonomic nervous system. Oxytocin is synthesized not only in the central nervous system, but also in the luteal cells of the ovary, in the uterus and fetal membranes.

The secretion of oxytocin increases in response to irritation of the cervix, vagina and nipples. It is quite difficult to record an increase in oxytocin levels during childbirth, since it is released in pulses and is quickly destroyed by cystinyl aminopeptidase in the blood. However, the most noticeable increase in oxytocin secretion occurs during the second stage of labor in response to cervical and vaginal distension. Estradiol stimulates the secretion of oxytocin, and the ovarian peptide hormone relaxin suppresses it. Factors influencing the secretion of ADH also affect the secretion of oxytocin, but to a lesser extent. Thus, alcohol consumption suppresses the secretion of oxytocin, and pain, dehydration, bleeding and hypovolemia, on the contrary, stimulate it. The peripheral action of oxytocin is unlikely to have any adaptive significance in these conditions, however, it is possible that it is involved in the central mechanisms of blood pressure regulation. However, therapeutic doses of oxytocin can suppress the excretion of water by the kidneys, which, if used carelessly, sometimes leads to water intoxication.

Oxytocin for postpartum uterine bleeding:

Sometimes Oxytocin is indicated after termination of pregnancy or birth of a child. It eliminates uterine hypotonicity, preventing bleeding and endometritis.

• IV drip infusion (80–160 drops/min.): 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.
• IM administration: 5 IU/ml Oxytocin after separation of the placenta.

Increased milk separation. Oxytocin is used to prevent mastitis due to milk stagnation. And also, it stimulates the functioning of the mammary glands and normalizes the movement of milk through the ducts: IM - 2 IU.

Oxytocin to stimulate lactation in the postpartum period - IM or intranasally, 0.5 IU 5 minutes before feeding.

When giving birth in a breech presentation - 2-5 IU.

Premenstrual syndrome - intranasally, from the 20th day of the cycle to the 1st day of menstruation.

During a cesarean section (after removal of the placenta), the drug is injected into the uterine wall at a dose of 3-5 IU.

Careful regular monitoring during labor reduces the risk of postpartum bleeding.

Improper use of the drug is dangerous for both mother and baby.

Analogs

Analogs

There are analogues of the drug Oxytocin on the pharmaceutical market. All of them are aimed at stimulating the smooth muscles of the uterus during childbirth. Thus, the following substitute drugs can be distinguished:

• Syntocinon. The active substance is a nonapeptide identical to the hormone oxytocin. Stimulates the muscles of the uterus and is used during childbirth, when the number of specific receptors for the hormone is increased in the myometrium;
• Oxytocin-Vial is a Russian-made drug that increases tone and increases myometrial contractions;
• Oxytocin-Grindeks is a Latvian synonym for Oxytocin;
• Oxytocin-MEZ is a drug that has virtually no vasoconstrictor and antidiuretic effect; the solution does not cause contraction of the intestinal or bladder muscles;
• Oxytocin-Richter – provides a myotonic effect, which occurs 3–7 minutes after administration and lasts 2–3 hours;
• Oxytocin-Ferein - stimulates uterine contractions, labor, eliminating hypolactation.