Misoprostol and the debate over off-label drug use.

Many readers will be surprised to learn that antenatal betamethasone is not licensed by the UK Medicines and Healthcare products Regulatory Agency (MHRA, formally the Medicines Control Agency) to prevent neonatal respiratory distress syndrome in pregnancy. Nor is oxytocin 10 units im licensed to prevent postpartum haemorrhage. However, oxytocin 5 units iv is licensed to treat a missed miscarriage and norethisterone (days 19–26) is licensed to treat menorrhagia despite now being considered ineffective and outdated (Table 1). Clearly, drug licensing is not proof of effectiveness and many drugs of proven efficacy are not licensed. It is also clear that, although drug companies have a responsibility to re-apply for their licence every five years, the scrutiny of these repeat applications by the MHRA is inadequate. This article will examine the role of drug licensing, especially with regard to the controversy over the use of misoprostol.