The nonequilibrium properties of strongly coupled plasmas are investigated taking into account reaction and diffusion processes. The starting point is quantum kinetic equations for systems with chemical reactions involving many‐body effects like screening, self‐energy, and medium‐dependent scattering. The influence of these effects on the kinetics of reaction and diffusion processes is discussed. Generalized expressions for the coefficients of impact ionization and diffusion are derived exhibiting a strong density dependence due to the many‐body effects. Solving the reaction‐diffusion equation (RDE) for a dense hydrogen plasma, nonlinear phenomena such as bistability, running ionization fronts, and droplet formation are obtained.