In the title compound, C(9)H(10)N(4)O(2), the pyridine ring is twisted by 16.5 (1)° from the mean plane defined by the remaining non-H atoms. An intra-molecular N-H⋯N inter-action is present. In the crystal, inter-molecular O-H⋯N and N-H⋯O hydrogen bonds link mol-ecules into layers parallel to the bc plane. The crystal packing exhibits π-π inter-actions indicated by the short distance of 3.649 (1) Å between the centroids of the pyridine rings of neighbouring mol-ecules.