Abstract: A method and apparatus for intermittent administration of supplemental oxygen to chronic obstructive pulmonary disease patients programmed for specific oxygen needs for each patient. Patient's arterial blood oxygen level is measured while supplying oxygen to determine the time required to reach a desired level and it is again measured without supplemental oxygen to determine the time required to diminish to a second, lower particular level. These two time intervals are applied as a program to apparatus connected to a supply of oxygen having valve and time controls to provide a regulated flow of supplemental oxygen to a nasal cannula for a preset time and to shut off the flow for a preset time sequentially and repetitively. The apparatus is powered by the energy of the gas itself either directly by gas powered controls and valves or indirectly with electrically powered controls and valves with gas power operating an electric generator to supply the necessary electrical power.