Dinoprostone

Pharmacological properties

dinoprostone or prostaglandin e2 (pge2) belongs to natural unsaturated fatty acids.

Prostaglandins have very different pharmacological properties, including the ability to stimulate organs that have smooth muscles, and modulate organ responses to other hormonal stimuli.

Dinoprostone, applied endocervically, promotes cervical maturation in patients with negative induction parameters. The mechanism of action of the drug is not fully understood. However, it has been experimentally established that in humans, the drug increases the BCC in the tissues of the cervix as it does in the initial stages of spontaneous delivery. These data clearly indicate that endocervical use of dinoprostone stimulates the hemodynamics of the cervix, thereby contributing to its maturation.

Pharmacokinetics In the body, prostaglandins are rapidly formed from the corresponding free polyunsaturated fatty acids. These compounds have a pronounced effect even in a minimal amount, and then quickly transform into inactive metabolites.

After endocervical administration at a dose of 0.5 mg (gel), the concentration of dinoprostone in the blood plasma (in the peripheral circulatory system) reaches a maximum after 30–40 min, after which it rapidly decreases to the initial level, regardless of the level of contractile activity of the uterus.

T_½ dinoprostone after injection is 1 min, while for each of the main metabolites it is ≈8 min.

Indications

The drug is prescribed for maturation of the cervix in pregnant women with full or near term pregnancy, if necessary, the induction of labor for therapeutic or obstetric reasons.

Application

For the correct administration of the drug, the patient must be in a prone position, and the cervix must be visualized using a vaginal mirror.

Gently inject the syringe into the cervical canal (directly under the internal pharynx of the cervix) and carefully use the catheter to enter the entire contents of the syringe (0.5 mg dinoprostone = 3 g Prepidil gel), after which the catheter is removed. Prepidil should not be administered above the level of the internal pharynx of the cervix. After administration of the gel, the patient should lie on her back for at least 15 minutes to minimize leakage of the gel.

The contents of the syringe are intended for use in only one patient. You should not try to inject a small amount of the gel remaining in the catheter. The syringe, catheter and other parts of the packaging of the drug must be disposed of after use.

Syringe Instructions

Remove the sterile syringe and sterile catheter from the packaging.

1. Remove the protective cap (to use it as a piston).

2. Install the protective cap in the syringe.

3. Attach the catheter to the syringe firmly (a click should be heard) and inject the contents of the syringe into the patient.

Contraindications

- patients with hypersensitivity to dinoprostone or any auxiliary substances of the gel;

- Patients who are contraindicated in stimulating labor;

- with multiple pregnancy;

- women who have ≥6 full-term pregnancies;

- if the fetal head is not present in the birth canal;

- in the presence of scars on the uterus (after cesarean section, hysterotomy, etc.);

- if the size of the fetal head does not match the pelvis of the mother;

- with a change in fetal heart rate, which indicates fetal distress syndrome;

- if there are obstetric conditions in which the risk / benefit ratio for the mother or fetus is in favor of surgical intervention;

- in the presence of abnormal uterine bleeding or discharge from the genital tract during pregnancy during an unexplained etiology;

- with unsanitary presentation of the fetus;

- with infectious diseases of the lower genital tract;

- history of severe and / or traumatic birth;

- with the presentation of the fetus above the plane of entry into the pelvis;

- for diseases of the heart, lungs, kidneys or liver in the active phase;

- with rupture of the fetal bladder.

Side effects

The frequency and severity of side effects caused by the use of dinoprostone depend on the dose of the drug and to some extent are determined by the route of administration. during the use of the drug prepidil, the following side effects were noted.

At mother

On the part of the immune system: hypersensitivity reactions, such as: anaphylactic reactions, anaphylactic shock, anaphylactoid reactions.

From the respiratory system, chest and mediastinal organs: wheezing, shortness of breath, feeling of lack of air, cough.

From the gastrointestinal tract: diarrhea, nausea, vomiting.

From the musculoskeletal system and connective tissue: back pain.

Effect on pregnancy, the postpartum period and perinatal conditions: impaired uterine contractility (increased frequency, tone or duration), uterine rupture, placental rupture, pulmonary embolism with amniotic fluid, rapid opening of the cervix.

From the reproductive system and mammary glands: sensation of heat in the vagina.

General disorders and disorders at the injection site: fever, pain.

From the side of the heart: cardiac arrest.

From the vascular system: AH.

From the respiratory system: AD, bronchospasm.

In the fetus / newborn

Influence on perinatal conditions: stillbirths, premature births, worsening health status of newborns (7 points on the Apgar scale), fetal acidosis.

Research: fetal distress syndrome, changes in fetal heart rate.

Sometimes body temperature may increase and leukocytosis may occur, but soon after treatment is stopped, the indicators usually normalize.

As with all intrauterine injections, the risk of developing local infections in extra-amniotic procedures must be considered. In such cases, infections need to be treated.

During post-marketing observations, an increased risk of developing DIC blood syndrome in the postpartum period was described in patients who underwent birth induction with pharmacological agents, in particular dinoprostone or oxytocin (see SPECIAL INSTRUCTIONS). However, the expected frequency of this adverse event is low (1 case per 1000 births).

special instructions

This drug is used only in a hospital setting.

Prepidil should be prescribed with caution in patients with a history of epilepsy, persons with impaired cardiovascular system, a history of liver or kidney function, as well as with BA (or history of BA), glaucoma (or with increased intraocular pressure). The use of the drug is contraindicated in ruptured chorioamniotic membranes.

Before and during the use of the drug, it is recommended to conduct continuous electronic monitoring of uterine activity and fetal heart rate; It is also recommended to monitor the characteristics of the cervix (opening, softening and expansion) for the timely detection of adverse reactions such as hypertonicity, uterine tetany or fetal distress syndrome.

Patients who develop uterine hypertonicity or its increased contractile activity or who have an unfavorable profile of fetal heart contractions should be managed in a way that ensures the general safety of the mother and the fetus.

As with any other means of stimulating labor, in case of excessive uterine activity or pain in the uterus, the risk of uterine rupture should be considered.

Before using the drug Prepidil, it is necessary to carefully evaluate the proportional ratio of the size of the fetus and pelvis.

High-dose therapy in animals for several weeks has shown that prostaglandins belonging to group E and F can cause proliferation of bone tissue. A similar effect was observed in newborns receiving long-term therapy with PGE₁. With short-term therapy with Prepidil, a similar effect on bone tissue was not observed.

It is necessary to prevent the introduction of Prepidil gel above the level of the internal pharynx of the cervix, since cases of hyperstimulation of the uterus were noted with extraamniotic administration of the drug.

Women over the age of 35 who have had complications during pregnancy and women with a gestational age of 40 weeks have an increased risk of developing DIC in the postpartum period.

In addition, these same factors can increase the risk associated with induction of labor (see ADVERSE EFFECTS). Therefore, for such patients, dinoprostone should be used with caution.

In the early postpartum period, appropriate measures should be taken as soon as possible to identify the possible onset of fibrinolysis.

The clinician must take into account the fact that the intracervical administration of dinoprostone gel can lead to unpredictable ruptures, followed by embolization with antigenic tissue and the development of a rare pregnant anaphylactoid syndrome (embolism with amniotic fluid).

Use during pregnancy and lactation

Dinoprostone is indicated for use in women with a full or near-term pregnancy or during childbirth.

Pge₂ caused an increase in the incidence of congenital skeletal abnormalities in rats and rabbits. The presence of embryotoxic properties of dinoprostone in rats and rabbits has been established, therefore, any dose of the drug that causes a prolonged increase in uterine tone may pose a risk to the embryo or fetus (see SPECIAL INSTRUCTIONS).

Prostaglandins pass into breast milk in very low concentrations. There were no differences in the concentration of the drug in breast milk of women who gave birth prematurely and women who gave birth at the appropriate time.

Children. The drug is not intended for use in children.

The ability to influence the reaction rate when driving vehicles or working with other mechanisms. The drug is used only in a hospital setting.

Interactions

The effect of oxytocin with the introduction of exogenous prostaglandins can be enhanced. therefore, the simultaneous use of these two drugs is not recommended. with the consistent use of these drugs, it is recommended to carefully monitor the patients health. it is recommended to adhere to a time interval of at least 6 hours between the use of oxytocin and dinoprostone.

Overdose

Prepidil is intended for use only in single doses, therefore, overdose symptoms can occur only in individual patients with hypersensitivity to the drug. since clinical trials of prostaglandin antagonists currently have not yielded sufficient results to provide recommendations, treatment for overdose is still symptomatic.

An overdose of the drug can be manifested by uterine hypertonicity or a pathological increase in the intensity or frequency of its contractions, which can lead to fetal distress syndrome.

Due to the transient nature of PGE₂-induced myometrial hyperstimulation, it was found that conservative treatment is effective in most cases of overdose, that is, a change in body position and the use of oxygen for the mother are indicated.

If excessive stimulation of the uterus (and / or fetal distress syndrome) is not resolved after discontinuation of treatment, intravenous administration of β-adrenergic agents may be appropriate. With the ineffectiveness of tocolytic agents, immediate delivery is recommended.

Storage conditions

In the refrigerator at a temperature of 2–8 ° c.