Dr. Oz drew on his medical background for a medical emergency at a political meeting ... jumping in to help a man who fell unconscious.
Sources close to the situation tell TMZ ... Oz was next in line to speak at Saturday morning's Pennsylvania Republican Caucus Meeting outside Pittsburgh when suddenly a state committee member collapsed.
We're told Dr. Oz rushed over and quickly lowered the man to the ground ... tending to him while he appeared to suffer a seizure and lost consciousness.
Our sources say Oz also helped move the man to a flat surface outside the meeting room, where another seizure-like episode occurred.
We're told EMS eventually arrived and transported the man to a local hospital, and the guy was conscious and conversing with Oz as EMS took him away.
Our sources say Dr. Oz went on stage for his scheduled remarks after the incident ... and following the caucus, he got in touch with the man and learned he's in stable condition at a hospital.
As you know ... Dr. Oz is running for a U.S. Senate seat in Pennsylvania, switching gears to politics after a successful career as a TV doctor.
Dr. Oz tells TMZ ... "I am a doctor first and always will be, so I responded immediately to a call for help when a nearby man collapsed. Following the lessons learned from a life in medicine, I did my job until EMS arrived to transport him to a nearby hospital."
It's not the first time Oz has been in the right place at the right time for a medical emergency ... as we first told you, he saved a man's life at an airport in March using CPR and a defibrillator.