  We study how electron-electron (e-e) interactions affect the current carried
by excited electrons and holes in Dirac systems such as graphene or topological
insulators. We find that the current shows distinctly different behavior for
e-e collisions involving the electron or the hole. Most surprisingly, for
positive Fermi energy, collisions of the electrons can substantially increase
the current. This remarkable amplification of the current can be of the order
of $\sim 10\%$ per scattering event. It also causes a strong suppression of the
overall current relaxation rate of a photoexcited electron-hole pair, with the
amplification of the electron current making up for a fast decay of the hole
current.
