The accident happened around 10:30 p.m. on Route 17 South in Rutherford.
Authorities say 43-year-old Soscia Salo, of Lyndhurst, was driving northbound in the southbound lanes when she collided head-on with the other driver at Highland Cross.
Arriving officers found two vehicles with significant front-end damage, and both drivers needed to be extricated before they were rushed to Hackensack University Medical Center.
The victim is in critical condition, while Salo was listed in serious condition. She is charged with assault by auto and possession of a controlled substance after five bags of heroin were found inside her car. She was also issued motor vehicle summonses for reckless driving, driving on the wrong side of a divided highway, and possession of a controlled substance in a motor vehicle.
Route 17 was back open for traffic on Tuesday morning.
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