Objective(s):In this study, the impact of thiamine (Thi), N-acetyl cysteine (NAC), and dexamethasone (DEX) were investigated in axotomized rats, as a model for neural injury.Materials and Methods:Sixty-five axotomized rats were divided into two different experimental approaches, the first experiments included five study groups (n=5): intrathecal Thi (Thi.it), intraperitoneal (Thi), NAC, DEX, and control. Cell survival was assessed in L5DRG in the 4thweek by histological assessment. In the second study, 40 animals were engaged to assessBcl-2,Bax,IL-6, andTNF-αexpression in L4-L5DRG in the 1stand 2ndweeks after sural nerve axotomy under treatment of these agents (n=10).Results:Ghost cells were observed in morphological assessment of L5DRG sections, and following stereological analysis, the volume and neuronal cell counts significantly were improved in the NAC and Thi.it groups in the 4thweek (P<0.05). AlthoughBcl-2expression did not show significant differences,Baxwas reduced in the Thi group (P=0.01); and theBcl-2/Baxratio increased in the NAC group (1stweek,P<0.01). Furthermore, theIL-6andTNF-αexpression decreased in the Thi and NAC groups, on the 1stweek of treatment (P≤0.05 andP<0.01). However, in the 2ndweek, theIL-6expression in both Thi and NAC groups (P<0.01), and theTNF-αexpression in the DEX group (P=0.05) were significantly decreased.Conclusion:The findings may classify Thi in the category of peripheral neuroprotective agents, in combination with routine medications. Furthermore, it had strong cell survival effects as it could interfere with the destructive effects ofTNF-αby increasingBax.