In some recent papers, the use of random forces has been related to a systematic breakdown of the fluctuation theorem. In the framework of nonequilibrium molecular dynamics, we provide a derivation of this theorem for systems driven by both deterministic and stochastic forces. It turns out that it is still valid and describes the total dissipation, explicitly the sum of two dimensionless works for which fluctuation relations may fail. We numerically study their range of validity, comment on experimental results, and point out in which limit a noise can be neglected.