  We studied the Raychaudhuri equation in Kaluza-Klein space-time. We derived
an additional term that is solely due to Kaluza-Klein's unification. This term
affects the defocus of world lines near the singularity of charged
higher-dimensional black holes. We illustrated it with a static
higher-dimensional black hole generated by Einstein-Maxwell equations. It has
been found that the term derived modifies the repulsive effect of kaluza Klein
scalar on world lines. We proved some mathematical theorems which give an
insight into the interior of the black holes.
