ONE in every 61 drivers have tested positive to illicit drugs in Victoria, police figures reveal.

More than 122,000 drivers have been tested by Victoria Police since its world first random drug testing program was introduced five-and-a-half years ago.

Of those, almost 2,000 motorists tested positive, with speed (83 per cent), cannabis (29 per cent) and ecstasy (15) per cent the most common substances detected.

Drug driving was as life-threatening as drink driving or speeding, Victoria Police traffic drug and alcohol Inspector Martin Boorman said.

"Drivers who have recently consumed cannabis or an amphetamine-based substance are at the same risk as having a crash as a driver with a blood alcohol concentration level above 0.05," Insp Boorman said.

"We have taken 2000 dangerous drivers off the roads with this program, and we'll continue coming up with new ways to catch more."

Tough enforcement, however, may be curbing the problem.

Of the 22,473 drivers tested for drug use in the past six months, 336 drivers registered a positive result - or 1 in 69, Insp Boorman said.

Almost a third of those drivers were found in regional Victoria.

"We know that some country drivers have the attitude that they won't get caught - but we have the capacity to test drivers anywhere, at any time," Insp Boorman said.

"Our drug testing program continues to expand across the state and motorists can expect to be drug tested by Double-Trouble Buses or police cars - marked or unmarked."