How misoprostol works
Misoprostol is a synthetically produced derivative of the tissue hormone prostaglandin E1 (i.e. a so-called prostaglandin E1 analog). It can dock onto certain glandular cells of the gastric mucosa (parietal cells) and thus inhibit the release of gastric acid. This can help to prevent acid-related ulcers in the stomach and duodenum.
The smooth muscles of the uterine wall also have docking sites (receptors) for prostaglandins such as misoprostol. When the active substance binds there, it triggers contractions of the uterine muscles (contractions). Prostaglandins such as misoprostol also promote the preparation of the cervix for birth: it becomes softer and shorter in order to create good conditions for the approaching passage of the baby.
When is misoprostol used?
In Germany, a combination preparation (tablets) containing the active ingredients diclofenac and misoprostol has been approved for adults with osteoarthritis or rheumatoid arthritis: diclofenac relieves the inflammatory processes and pain caused by the disease. However, it can cause gastrointestinal ulcers as a side effect, which the added misoprostol is intended to prevent.
Misoprostol is also very often given in German clinics as a contraceptive (to induce labor), also in tablet form. It is considered to be very effective and can reduce the number of caesarean sections required. It is used for induction of labor without approval (“off label”), i.e. without having been specifically investigated and tested for this area of application.
In other countries, misoprostol tablets are also very often given as an oxytocic – sometimes without approval (as in Germany), sometimes with approval. Even the World Health Organization (WHO) recommends low doses of misoprostol as an effective means of inducing labor – due to its good risk-benefit balance.
How misoprostol is used
The combination tablets with diclofenac and misoprostol for the treatment of osteoarthritis and rheumatoid arthritis are only approved for adults. Unless otherwise prescribed, patients take one tablet twice a day with plenty of liquid with food.
To terminate a pregnancy with medication, the woman first takes a single dose of mifepristone. After 36 to 48 hours, she receives a single dose of misoprostol under medical supervision. A miscarriage occurs in the following hours.
What are the side effects of misoprostol?
The most common adverse effects of the combination tablets with diclofenac and misoprostol are abdominal pain, diarrhea, nausea and other upper abdominal complaints.
The misoprostol preparation for abortion most frequently triggers nausea, vomiting, diarrhea and abdominal pain. The latter are caused by the desired uterine contractions.
The misoprostol tablets for induction of labor (without approval) can cause the amniotic fluid to be contaminated by “child saliva” (meconium: the child’s first stool). Normally, meconium is only excreted in the first few days after birth. However, passing meconium while still in the womb under the influence of the misoprostol preparation should not have any undesirable effects on the child.
On the other hand, the oral misoprostol preparation can result in altered labor activity: Misoprostol can overstimulate the uterus, causing a sharp increase in the number of contractions – up to and including a “labor storm” (very many contractions at very short intervals). Possible consequences can include a lack of oxygen in the child (with the risk of brain damage) and tears in the uterine wall. There are also individual reports of deaths following the administration of misoprostol tablets to induce labor.
What should I bear in mind when using misoprostol?
The combination tablets with diclofenac and misoprostol must not be taken by women who are pregnant or planning a pregnancy. Women of childbearing age should only use the medication if they are using reliable contraception. If pregnancy does occur, the medication must be discontinued immediately.
Patients should first discuss the simultaneous use of the combined tablets with other medications with a doctor or pharmacist.
How to obtain medication with misoprostol
The prescription-only combination preparation with diclofenac and misoprostol is available from pharmacies.
Misoprostol preparations for abortion and induction of labor are usually administered by doctors or medical staff.
How long has misoprostol been known?
In the 1980s, the pharmaceutical manufacturer Pfizer launched an oral misoprostol preparation for the prevention and treatment of stomach and duodenal ulcers on the German market. It was withdrawn from the German market in 2006. In other countries, the preparation is also approved as a stomach medicine. It can be imported from there to Germany, where it is then used in obstetrics in many clinics.
The drug Cytotec with the active ingredient misoprostol for inducing labor is suspected of causing serious complications. You can find answers to all the important questions on this topic here.
