NSW drivers will now be tested for cocaine as authorities work to curb the state's horror road toll which has seen 17 people die this year after 392 people were killed in 2017, which was an eight-year high.

Premier Gladys Berejiklian on Monday announced a raft of tough new measures, including doubling the number of roadside drug tests by 2020, increasing penalties for drug drivers and looking to reduce the risk posed by people taking prescription drugs.

The announcement comes as 29-year-old actor Jessica Falkholt clings to life in a Sydney hospital after her family was wiped out in a Boxing Day car crash involving a driver with a shocking driving history on his way home from a Nowra methadone clinic.

"Too many people and too many families have been left distraught over what should be a very happy time of the year," Ms Berejiklian told reporters in Sydney.