Carter, 25, was behind the wheel of a vehicle observed committing a traffic violation when police stopped him Saturday night in downtown Huntington Beach, police Lt. Dave Bunetta said.
"The officer that stopped him noticed some traffic violation was occurring," Bunetta said. "When he was contacted by the officers they conducted an investigation which would include field sobriety tests and they formed the opinion he was under the influence."
Carter was arrested and booked for investigation of drunken driving and his vehicle was impounded, Bunetta said. The type of vehicle wasn't disclosed.
It wasn't known how long Carter was in jail. Motorists arrested for drunken driving in Huntington Beach are typically held for a minimum of four hours then, after evaluation, are released with a citation ordering them to appear in court within 45 days, Bunetta said.
"Nick Carter deeply regrets the current situation. He is on doctor-prescribed medication and was unaware of its interaction possibilities," Carter publicist Juliette Harris said in a statement Monday.
The Backstreet Boys, whose hits include "I Want it That Way," "Shape of My Heart" and "Show Me the Meaning of Being Lonely," recently announced a 13-city tour that will start March 21 in New York.
Jive Records said they will perform all their hits plus songs from their upcoming CD. The Backstreet Boys haven't produced a new album since 2000's "Black & Blue."
Carter released a solo album in 2002.