Resonant wave absorption in the ion cyclotron frequency range gives rise to a quasi-linear diffusion in velocity space for the heated particles. The present analysis investigates the resulting distribution functions in the presence of ICRH using the fundamental as well as the second-harmonic cyclotron frequency. Particular emphasis is given to the study of the anisotropic high-energy ion tails. The results include explicit expressions for the ion distribution in the bulk and tail regions as well as important information on the RF-induced anisotropy.