Abstract: Allergic reactions have been associated with cloves, black pepper and mast cells. The presence of mast cells and renal fibrosis has also been reported and in line with an ongoing investigation on the effects of excessive consumption of Yaji - the complex Nigerian meat sauce, this study was designed to correlate the individual and combined effects of the excessive consumption of Yaji-spices (ginger, clove, red pepper and black pepper) on the histology of the kidney, using 12 adult rabbits. The animals were divided into six groups of two (2) each (A, B, C, D, E and F). Groups B, C, D, E and F were the test groups whereas group A is the control. For 21 days, test group B was fed with feed and a combination of all the yaji-spices (3g each) while test groups C, D, E, and F were fed with feed and 3g each of the spices per day respectively. The histological observations showed that there were no effect on the kidneys in test groups C and E whereas in B, D and F, there were distinct round basophilic bodies in the interstitium of the renal cortex, which were suspected to be mast cells, and hence, implicating cloves and black pepper. This result suggests a possible mechanism of renal damage that is clove and black pepper feeding-induced, duration dependent and with mast cell mobilization into the kidney, that may then trigger renal fibrosis.