This research paper presents a theoretical investigation of the combined effects of chemical reaction and heat source on blood flow via a tapered vessel in the presence of angle of inclination and magnetohydrodynamics. The continuity, momentum and concentration equations are used to model the proposed problem in terms of nonlinear partial differential equations. These equations along with the initial and boundary conditions is made dimensionless and then solved numerically using power series method. The computational results are presented graphically for the blood velocity, temperature, and concentration distributions in terms of the different parameter values used in this analysis. The study shows that the existence of the controlling parameters significantly impacts the characteristics of the flow.