A driver overdosed on heroin and was found unconscious at a red light in Islandia Thursday, Suffolk police said.

Robert Moore, 23, of West Islip, still had his foot on the brake on Motor Parkway near Express Drive South, but had stopped breathing by the time two passing motorists pulled over to help him about 10:20 a.m., police said.

advertisement | advertise on newsday

Fourth Precinct Officer Kathleen Cotter, a member of the force’s Medical Crisis Action Team, known as MedCAT, gave the overdose antidote, Narcan, in a nasal spray to Moore, who regained consciousness, police said.

He was treated and released at St. Catherine of Siena Medical Center in Smithtown, police said.

Moore was charged with driving while ability impaired by drugs and was being held overnight at the Third Precinct, police said. He is scheduled to be arraigned Friday at First District Court in Central Islip.