Aim:Phenyramidol (Phe) is an efficacious and well-tolerated analgesic which is not known the effect in pregnancy, used in the treatment of the acute conditions of lumbago, acute musculoskeletal pain. The purpose of this study was to investigate the effects of Phe on neural development in an early chicken embryo model.Material and Methods:Sixty fertile non-pathogenic Super Nick eggs were incubated for 24 h and divided into four groups of 15 eggs each. Phe was administrated through the sub-blastoderm, and the eggs were incubated for another 24 h. All eggs were opened after 48 h of incubation, and the embryos were evaluated morphologically and histopathologically.Results:In Group 1 (control group), none exhibited NTDs (0%), 1 (6.6%) was undeveloped, in Group 2 (low dosages), 1 did not develop (6.6%), in Group 3 (normal dosages), 2 (13.4%) had NTDs, 1 (6.6%) was undeveloped, in Group 4 (high dosages), 5 (33.3%) had NTDs, 2 (13.3%) were undeveloped. Conclusion:In light of the results, it was determined that the use of increasing doses of Phe led to defects in midline closure in early chicken embryos. This is the first report in the literature on Phe used in an early chicken embryo model.