The aim of this study is to evaluate the effects of herapeutic doses and ¼ LD50 of lamotrigine on the visceral structure of albino rat fetuses. This study was conducted over a period of 6 months extending from October 1, 2011 to February 1, 2012. Sixty adult non-pregnant female albino rats and 30 male rats of the same strain, weighed 150-200 grams, were purchased from the Animal House of The Faculty of Medicine, Assiut University. Sixty pregnant rats were used in this study and were classified into three groups: a) Control Group (I): consisted of 20 pregnant females with normal saline administration. b) Study Group II: consisted of 20 pregnant females with therapeutic dose of lamotrigine oral administration of 5.4mg /d of lamotrigine, and (c) Study Group II: consisted of 20 pregnant females with ¼ LD50 oral administrations of 32mg /d. One hundred sixty eight fetuses (94 fetuses of GIIa and 74 fetuses of GIIb) and 134 fetuses from control group, were fixed in bouin’s solution (aqueous saturated solution of picric acid 70% formalin 25% , glacial acetic acid 5%) for visceral examination. The study revealed that no internal visceral abnormalities were detected in fetuses of control and therapeutic doses of lamotrigine treated groups. Fetuses of the ¼ LD50 treated group showed internal abnormalities in the heads cross sections only, while other levels sections showed no differences from control. Lamotrigine should not be regarded totally safe drug during pregnancy until its safety is established in a large scale randomized study with long term follow-up.