Junta number two General Prawit Wongsuwan, 72, received medical attention in the middle of the mobile Cabinet meeting on Tuesday after suffering a stomach ache and diarrhea on the job.
Prime Minister General Prayut Chan-o-cha said after the meeting that Prawit had suffered only minor dyspepsia.
Two military doctors rushed into the meeting venue at Ubon Ratchathani University to check on General Prawit, it was reported.
Soon after, medics were seen taking equipment inside the building from an ambulance already on stand-by. After 20 minutes, they returned the equipment to the ambulance.
Officials also prepared and cleared the road in case of emergency.
The incident broke out on Tuesday as the mobile Cabinet meeting was in session in Ubon Ratchathani Province.
Deputy Prime Minister Prajin Juntong later reported that Prawit had had a stomach ache and diarrhea. Only after he had completed his presentation to the Cabinet did Prawit ask the Premier to allow him to go to hospital, said Prajin.