Studies of mass transfer in a porous medium are of interest to researchers as a result of its various uses in different fields of engineering practices. This work examined the steady flow of a reactive variable viscous fluid in a porous cylindrical pipe. Dimensionless variables were used to dimensionalize the governing equations. A regular perturbation technique was employed to obtain an approximate solution of the resulting dimensionless non-linear equations. Numerical simulation was done to get the threshold values for the flow parameters under consideration. The effects of viscous heating and permeability parameters on the steady flow were studied and reported.