A Harrington Park woman has been charged following investigations into a serious crash in the state's north last October.
A Suzuki Vitara and Suzuki Swift collided head-on on Myocum Road, Ewingsdale about 11am on October 25, 2018.
A 32-year-old woman, of Harrington Park, was behind the wheel of the Vitara. She suffered minor injuries and was taken to Tweed Heads Hospital for treatment.
The Swift driver, a 19-year-old Mullumbimby woman, was taken to the Gold Coast University Hospital with serious injuries, including a fractured spin and sternum.
Police launched an investigation into the circumstances surrounding the crash.
The Harrington Park was arrested about 8.30pm on Sunday, April 14.
She was taken to Tweed Heads Police Station and charged with 21 offences, including driving under the influence of drugs, dangerous driving, causing bodily harm by misconduct and possession of prohibited drugs.
The woman was given bail to appear in Byron Bay local court on June 27.