We investigate the non-geodesic motion of a test particle inside a fluid in equilibrium, as described by the interior Schwarzschild solution, in the presence of a Poynting–Robertson-like dissipative force. The accelerated motion in the interior spacetime is (regularly) connected to the geodesic one in the corresponding external Schwarzschild background, mimicking physical conditions often occurring in spacetime regions close to stellar or compact objects. A similar analysis is repeated for the case in which the interior Schwarzschild solution is given by a Pant–Sah perfect-fluid solution. This latter case, supporting a polytropic equation of state for the interior fluid source, appears to be more appropriate for modeling situations of either stellar or cosmological interest.