Macroscopic field inhomogeneities increase the effective transverse relaxation rate R2*. In contrast to conventional models assuming ideal rectangular pulses, we developed an R2* correction model for Gaussian excitation pulses. After demonstrating the validity of the model in phantom measurements we measured 10 volunteers with 2mm and 4mm slice thickness, respectively. Uncorrected and corrected R2* values were assessed regionally and a significant effect of the correction was observed. An advantage of the proposed method is that it only requires two echoes, rendering it useful in clinical MRI.