A reversing valve (100) for a high-viscosity medium comprises a housing (10) having an inlet opening (23) and at least two outlet openings (21, 22), extending into a valve bore in which is mounted an axially displaceable valve stem (10, 10′). The valve stem comprises a groove by which the inlet opening (23) is alternatively to be connected to one of the outlet openings (21, 22). The groove has an axially extending inflow zone (12) and an axially extending outflow zone (11, 11′). The inflow and outflow zones are connected at both ends to a continuous annular channel by way of connecting channels (13, 14).