Misoprostol (Cytotec): What It Is Used For

What is misoprostol?

Misoprostol is an active ingredient used in gynecology for cervical ripening, dilation of the cervix, and induction of labour in women with an unfavourable cervix.

In the United States, the brand name mentioned in the source content is Cytotec.

How misoprostol works

According to the source content, misoprostol has several actions:

• It induces contraction of the uterine musculature.
• It acts as a blood vessel dilating agent.
• It has a mild bronchodilator effect on bronchial smooth muscle.
• In the gastrointestinal tract, it inhibits acid secretion by acting directly on gastric parietal cells.
• It decreases pepsin production.
• It stimulates duodenal bicarbonate secretion.
• It increases gastric mucus production.

Therapeutic uses in gynecology

The source content lists these gynecological uses:

• Cervical ripening and induction of term labour, especially when the cervix is immature and there are no fetal or maternal contraindications.
• Dilation of the cervix of the non-pregnant uterus before hysteroscopy or other gynecological procedures that require access to the uterine cavity.
• Induction of labour in women with an unfavourable cervix from the 36th week of pregnancy, when induction is clinically indicated.

How it is given

The source content describes vaginal use, including vaginal tablets and a vaginal release system. Administration should be done according to the product information and under appropriate medical supervision.

Vaginal tablets

• Cervical ripening and induction of term labour: 25 mcg at 4–6 hour intervals, up to a maximum of 100–150 mcg.
• Dilation of the cervix before procedures: 400 mcg 2 to 8 hours before in uteruses with no history of previous caesarean section or uterine scarring, and 2 to 4 hours before in uteruses with a history of previous caesarean section or uterine scarring.

Vaginal release system

• Used for induction of labour in women with an unfavourable cervix from the 36th week of pregnancy, when clinically indicated.
• The source content states that it releases misoprostol at approximately 7 mcg/h for 24 hours.
• The maximum dose is one vaginal release system (200 mcg).
• It should be administered by staff with obstetrics expertise in a hospital setting with continuous fetal and uterine monitoring available.

Important contraindications listed in the source

The source content lists the following situations where misoprostol should not be used for these gynecological indications:

• Hypersensitivity to misoprostol or prostaglandins.
• When oxytocic drugs are contraindicated or prolonged uterine contractions are considered inappropriate.
• History of cesarean section or major uterine surgery, in the context of cervical ripening and induction of term labour.
• Cephalopelvic disproportion.
• Suspicion or clinical evidence of fetal distress.
• History of difficult and/or traumatic delivery.
• Multiparity with 6 or more previous term pregnancies.
• Transverse fetal situations.
• Obstetric emergencies where surgical intervention is preferred.
• Multiple pregnancies.
• Unexplained vaginal discharge and/or irregular uterine bleeding during the current pregnancy.
• When vaginal delivery is not indicated, such as placenta previa or active genital herpes.
• Concomitant use of oxytocin and other stimulants of uterine contractions.
• Risk factors for amniotic fluid embolism, severe pre-eclampsia or eclampsia.

Warnings and precautions

The source content highlights the following precautions:

• Epilepsy or a history of epilepsy.
• Kidney and/or liver disease.
• Cardiovascular disease.
• Hypotension.
• History of cesarean section or major uterine surgery.
• Haemostatic disorders with hypocoagulability or anaemia.
• Ruptured chorioamnion membranes.
• Chorioamnionitis, hydatidiform mole, and intrauterine fetal death.
• Kidney failure, liver failure, and malnutrition are listed as situations where it is not recommended.
• Increased risk of postpartum disseminated intravascular coagulation in patients induced by physiological or pharmacological methods.

Vaginal release system safety note

The source content states that misoprostol may cause excessive uterine tachysystole that may not respond to tocolytics. It also says the vaginal delivery system should be removed immediately at the start of labour or if contractions become prolonged or excessive, or if there is a clinical complication in the mother or baby.

Interactions listed in the source

Pregnancy and breastfeeding

The source content states that misoprostol is contraindicated in pregnancy for general use, while also describing its specific use for induction of labour at term under medical supervision.

For breastfeeding, the source says it is excreted in breast milk, but the concentration is negligible within 5 hours of administration.

Side effects and adverse reactions listed

Vaginal tablets

• Nausea
• Vomiting
• Diarrhea
• Abdominal pain

Vaginal release system

• Fetal heart rate disorder
• Abnormal delivery affecting the fetus
• Meconium in the amniotic fluid
• Abnormal uterine contractions

What to verify in the official leaflet

If you are reviewing misoprostol for a specific situation, check the official medication guide or ask a pharmacist or doctor to confirm:

• The exact indication for use.
• The formulation being used, since tablets and vaginal release systems are not the same.
• Whether hospital monitoring is required.
• Any history of uterine surgery or other factors that may affect suitability.
• Possible interactions with other medicines you are taking.

FAQ

Sources and references

The original content states that it was written using clinical and molecular information from medicines authorised and marketed in the United States under the Unique Ingredient Identifier (UNII) by the FDA Substance Registration System and the United States Pharmacopeia.

For official product information, the source content points readers to the FDA medication guide database.