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Date of issue: October 2023, Version: 1.4

Strychnine, an alkaloid obtained from the seeds of the Strychnos nux-vomica, was formerly used in medicine and as a rodenticide. It has occasionally been found as a contaminant of herbal medications and drugs of abuse.

Strychnine is a selective blocker of post-synaptic glycine-mediated neuronal inhibition. As a consequence of exposure, action potentials are triggered by lower levels of circulating neurotransmitters, resulting in constant muscular contractions and convulsions. Death due to respiratory or cardiac failure may occur.

There are no published data available to support an assessment of fetal risk following exposure to strychnine in pregnancy. Owing to the potential severity of strychnine exposure, treatment of the pregnant patient should be the same as for the non-pregnant patient. Maternal toxicity is likely to be a major determinant of risk to the fetus after maternal strychnine exposure.

Where exposure to strychnine has occurred, even in cases which did not result in maternal toxicity, enhanced fetal monitoring may be warranted. Discussion with UKTIS is recommended.

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.

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