Activation of inflammatory pathways may contribute to the beginning and progression of many complications in the body. Current study was aimed to evaluate the status of acute phase response and inflammation by examining the alterations in the level of acute phase proteins due to the toxic effect of an immunosuppressive drug (tacrolimus). Aqueous suspension of tacrolimus powder (3 mg/ml) was orally given to four experimental groups of wistar rats. Control group was provided with normal drinking water and dissections were done after 6, 12, 24 and 48 h of tacrolimus dose. Densitometric analysis revealed considerable elevated level of some positive acute phase proteins, specifically C-reactive protein, haptoglobin and ceruloplasmin. While albumin and transferrin levels were found to be low as compared to control animals. The results obtained in this study revealed that tacrolimus resulted in the onset of acute phase response in experimental animals owing to its toxic potential.