The temperature and field dependence of the magnetization were measured on a single crystal of the antiferromagnet UIrGe in pulsed fields up to 51 T, and the specific heat in steady fields up to 18 T. At low temperatures, metamagnetic transitions are observed at critical fields Bc of 21 T and 14 T, applied along the b and the c axis, respectively. At 2 K, the magnetization jumps at Bc are 0.36 amp; 956;B U along the b axis and 0.28 amp; 956;B U along the c axis. The a axis is the hardest magnetization direction with a weak linear magnetic response. Both along the b and the c axis, Bcdecreases with increasing temperature. Consistent with the magnetization, the sharp anomalies observed in the specific heat obey the same dependence.