The non-muscarinic antispasmodics mebeverine hydrochloride, alverine citrate and peppermint oil are direct relaxants of smooth muscle in the gastrointestinal tract and are used for the symptomatic relief of irritable bowel syndrome where non-pharmacological interventions are inadequate. Alverine citrate is also used in the treatment of diverticular disease of the colon and dysmenorrhoea, due to its direct relaxant effects on uterine smooth muscle.
There are no adequate published data available to assess the potential teratogenic or fetotoxic effects of mebeverine hydrochloride, alverine citrate or pharmaceutical doses of peppermint oil. Therefore, limited conclusions can be provided regarding the risks posed to the fetus following maternal use of these products during pregnancy.
UKTIS has collected the outcomes of 70 pregnancies with non-muscarinic antispasmodic exposure, including 39 pregnancies exposed in the first trimester; no major anomalies were observed.
Based on the lack of published evidence relating to use of mebeverine hydrochloride, alverine citrate or therapeutic doses of peppermint oil in human pregnancy, use during pregnancy should only be considered if clinically necessary and where the benefits of good control of the maternal condition are considered to outweigh the unknown fetal risks.
Exposure to antispasmodics at any stage in pregnancy would not usually be regarded as medical grounds for termination of pregnancy or any additional fetal monitoring. However, 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.
This is a summary of the full UKTIS monograph for health care professionals and should not be used in isolation. The full UKTIS monograph and access to any hyperlinked related documents is available to NHS health care professionals who are logged in.
If you have a patient with exposure to a drug or chemical and require assistance in making a patient-specific risk assessment, please telephone UKTIS on 0344 892 0909 to discuss the case with a teratology specialist.
If you would like to report a pregnancy to UKTIS please click here to download our pregnancy reporting form. Please encourage all women to complete an online reporting form.