Corrections of orders ␣ 5 and ␣ 6 are calculated in the hyperfine splitting of the 2S state in the muonic hydrogen. The nuclear structure effects are taken into account in the one-and two-loop Feynman amplitudes by means of the proton electromagnetic form factors. The total numerical value of the 2S state hyperfine splitting in the muonic hydrogen is 22.8148 meV. This value can be considered as a reliable estimate in conducting a corresponding experiment with an accuracy 10 −5 . The value of the Sternheim hyperfine splitting interval ͓8⌬E HFS ͑2S͒ − ⌬E HFS ͑1S͔͒ is obtained with an accuracy 10 −6 .

Corrections of orders α 5 and α 6 are calculated in the fine structure interval ∆E f s = E(2P 3/2 ) − E(2P 1/2 ) and in the hyperfine structure of the energy levels 2P 1/2 and 2P 3/2 in muonic hydrogen. The obtained numerical values ∆E f s = 8352.08 µeV , ∆Ẽ hf s (2P 1/2 ) = 7964.36 µeV , ∆Ẽ hf s (2P 3/2 ) = 3392.59 µeV can be considered as a reliable estimate for the comparison with corresponding experimental data and for the extraction of the experimental value of the Lamb shift (2P − 2S) in muonic hydrogen.

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The contribution from the axial-vector meson exchange to the potential of the muon-proton interaction in muonic hydrogen induced by anomalous axial-vector meson coupling to two photon state is calculated. It is shown that such contribution to the hyperfine splitting in muonic hydrogen is large and important for a comparison with precise experimental data. In the light of our result, the proton radius "puzzle" is discussed.

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