We extend the dressed-atom approach to treat the interaction of a laser field with a semiconductor system. The semiconductor is modeled via a simple Kane band-structure scheme and the interaction with the laser field is incorporate through the renormalization of the semiconductor energy gap and conduction/valence effective masses. Far from resonances, such one-body approach allows the study of the effects of laser fields on a variety of optoelectronic phenomena in semiconductor systems for which the effective-mass approximation provides a good physical description. We calculate the effects originated by the laser-dressing on the donor and exciton peack energies in quantum-well heterostructures, and show that they may be quite considerable and observable.