SUMMARY: Gabapentin is structurally related to the neurotransmitter GABA (gamma-aminobutyric acid) and binds to the alpha2-delta subunit of voltage-gated calcium channels. Gabapentin is indicated as monotherapy or adjunctive therapy in the treatment of partial seizures with and without secondary generalization, and for the treatment of peripheral neuropathic pain. 

Epileptic women treated with anticonvulsants have a 2-3 fold increased risk of major congenital malformation in their offspring, i.e. approximately 10%. The most frequently reported malformations following anticonvulsant therapy are cleft lip, cardiovascular malformations and neural tube defects. The relative contribution of anticonvulsant therapy vs. the underlying maternal condition to the increased risk of malformations is undetermined. Exposure to multiple antiepileptic drugs has been associated with a greater risk of congenital malformations, therefore monotherapy is preferable where possible.

Sudden discontinuation of antiepileptic therapy is not recommended as it may lead to breakthrough seizures which could have serious adverse consequences for both mother and child. High dose folic acid (5mg/day) is recommended for all women with epilepsy. 

The currently available data do not demonstrate an increased risk of congenital malformations following gabapentin exposure or any pattern of malformations, however data is insufficient to state that there is no increased risk. Exposure to gabapentin at any stage in pregnancy would not usually be regarded as medical grounds for termination of pregnancy or any additional fetal monitoring.

Please report ALL cases of drug and/or chemical exposure in pregnancy to UKTIS by telephoning the service on 0844 892 0909 or by printing and completing a pregnancy reporting form, providing as many patient identifiers as possible to enable follow up of pregnancy outcome. This vital information enables UKTIS to provide evidence-based advice for future enquiries and to conduct surveillance of potential and known teratogens. 

For case specific advice please contact UKTIS on 0844 892 0909.