Police were called to Forest Road near the intersection of Scott Road in Peakhurst about 12.15am following reports of a three-vehicle crash.
Police were told a Kia sedan was travelling in a northerly direction and a Land Rover SUV in a southerly direction before the two vehicles collided in the south-bound lane.
The Kia continued and collided with a Hyundai sedan.
All occupants of the vehicles were treated for minor injuries at the scene before the passengers of the Land Rover were taken to St George Hospital for further treatment.
The 66-year-old male driver of the sedan was breath tested and allegedly returned a positive reading.
He was taken to Kogarah Police Station where he underwent a secondary breath analysis which returned an alleged reading of 0.162.
The man was charged with high-range PCA and negligent driving and refused bail, to appear at Parramatta Bail Court today.
Forest Road was closed in both directions but has now reopened.
Anyone with dashcam footage or information about the incident is urged to contact Crime Stoppers on 1800 333 000.