Recent progress in the evaluation of higher-order corrections to the continuum-model description of channeling radiation from MeV electrons is discussed. The most important corrections are found from thermal scattering, and to second order in a time-dependent perturbation expansion, a ‘phonon Lamb shift’ is obtained, caused by emission and absorption of virtual phonons. It turns out that the third-order thermal correction must be included since it contains a shift which is of the same magnitude or larger. The possible significance of the second-order level shifts due to electronic excitations is also considered.