Police found heroin in Redmond's car early on Tuesday morning after pulling him over for running a red light.
Redmond was booked on charges of possession of a controlled substance, a red light infraction and violating the terms of his probation, the Los Angeles Times reports.
He will remain in police custody until he appears in court to formally face these latest charges.
The 26-year-old was placed on probation in 2009 for bringing drugs into an LA jail.
Redmond was jailed when his mother Farrah Fawcett died from cancer in 2009. He was granted a temporary release so he could speak at her funeral.
Last summer, two narcotics offences against Redmond were dropped after he completed a stint in a drug diversion programme.
Ryan previously admitted that he's been heartbroken by Redmond's battles with addiction.