USE OF MEPTAZINOL IN PREGNANCY

Meptazinol is a centrally acting hexahydroazepine analgesic. It is currently licensed for the short-term treatment of moderate-to-severe pain, including post-operative pain, obstetric pain and pain associated with renal colic.

There are no published data on the therapeutic use of meptazinol in early pregnancy. All available data relating to meptazinol exposure derive from clinical trials investigating its use as an analgesic during labour, the majority comparing meptazinol to pethidine. Data relating to the risk of adverse pregnancy outcomes which may result from exposures during earlier stages of pregnancy are therefore unavailable. As meptazinol has mixed agonist and antagonist activity at opioid receptors, the potential for respiratory depression and neonatal withdrawal must be considered following maternal use close to delivery. Neonates with symptoms consistent with those caused by prenatal opioid exposure, including post-delivery withdrawal, have been reported following meptazinol use during labour. However, these data may be confounded by concomitant risk factors, such as delivery complications or other maternal exposures throughout pregnancy or during delivery. A single small study found no significant difference in one and five minute Apgar scores between meptazinol-exposed and unexposed control neonates.

Collectively, studies do not indicate significant differences in neonatal outcomes between infants born to women who received meptazinol during labour and those born to women who received pethidine.

Other risk factors may be present in individual cases which may independently increase the risk of adverse pregnancy outcome. Clinicians are reminded of the importance of consideration of such factors when performing case-specific risk assessments. Given the lack of data relating to exposure in early pregnancy, in such cases, detailed ultrasound scans should be considered to check morphological development.