Misoprostol is currently only approved by the Food and Drug Administration (FDA) in the US for the prevention and treatment of gastric ulcers resulting from chronic administration of non-steroidal anti-inflammatory drugs (NSAIDS). In some other countries dedicated products for several indications in OB/Gyn have been marketed or are expected in the next years.
Misoprostol has been extensively studied in reproductive health, and is widely recommended for the treatment of missed and incomplete miscarriages, the induction of abortion, and cervical preparation before uterine instrumentation, induction of labour and postpartum haemorrhage prophylaxis and treatment.
The use of drugs for off-label indications is legal, common practice, and not considered experimental if based on sound scientific evidence. Drug licensing is not proof of effectiveness and many drugs of proven efficacy are not licensed.
In all cases the evidence must be carefully considered and the benefit: risk ratio assessed before a drug is prescribed for an unlicensed indication.
Patients and their carers should be properly informed if a doctor prescribes a licensed drug for an unlicensed indication.
|Drug & Indication||Licensed indication?||BNF||RCOG|
|1.Oxytocin 10im to prevent PPH||No||Yes||Yes|
|2.Misoprostol for termination of pregnancy before 24 weeks||No||Yes||Yes|
|3.Antenatal betamethasone to prevent neonatal respiratory distress syndrome in premature deliveries||No||Yes||Yes|
|4.Clindamycin to treat haemolytic streptococci in pregnancy||No||No||Yes|
|5.Oxytocin 5 iv to treat missed miscarriage||Yes||No||No|
|6.Norethisterone (days 19-26) to treat menorrhagia||Yes||Yes||No|
All medications have potential adverse effects. Read about the potential problems with misoprostol and how to avoid them.
Uterine hyperstimulation is a serious complication of labour induction. It is defined as as single contractions lasting 2 minutes or more, or five or more contractions in a 10 minute period. It can cause impairment to uteroplacental blood flow and result in fetal heart rate abnormalities, fetal hypoxia and fetal damage.
Uterine hyperstimulation is mainly a concern with induction of labour at term, and is a risk with all induction methods. A Cochrane systematic review by Alfirevic et al of 76 studies found that oral misoprostol (doses of 20-25mcg given every 1-2 hours) have the same hyperstimulation rates as other induction methods.