An analysis is performed to study the unsteady hydromagnetic heat and mass transfer of blood in a time-dependent porous narrow blood vessel over a permeable inclined stretching surface under slip conditions. The unsteadiness in the flow, temperature and concentration fields is caused by the time dependence of the stretching velocity, surface temperature and the surface concentration. Thermal radiation, chemical reaction, velocity slip, thermal slip and concentration slips are considered. Similarity transformations are used to convert the governing time-dependent non-linear boundary layer equations for momentum, heat equation and species equations into a system of ordinary differential equations. The resulting non-linear coupled differential equations are solved numerically by using fourth order Runge–Kutta scheme together with shooting method. The influence of pertinent parameters on velocity, temperature, concentration, skin-friction coefficient, Nusselt number and Sherwood number has been studied and numerical results are presented graphically and in tabular form. Comparisons with previously published work are performed and the results are found to be in excellent agreement.