  The order $\alpha^4 (m/M) R_{\infty}$ shift of hydrogen P levels is found.
The corrections are predominantly of relativistic origin. Our approach is a
straightforward extension of that developed and applied by us previously to
positronium P levels. The corrections to the Lamb shift in hydrogen constitute
numerically \delta E(2 P_{1/2})=0.55 kHz, \delta E(2 P_{3/2}) =0.44 kHz.
