Alex Warren, 22, of Hazel Grove, who admitted the offence, was seen by police driving an Audi A3 in Eastgate in Louth at 11pm on February 24 this year and going over the speed limit.
In Boston this week, magistrates heard that he tested positive for cocaine and was arrested, later giving a blood sample showing 642 micrograms of the derivative of cocaine in his bloodstream, the legal limit being 50.
Warren told police he had taken cocaine the previous night.
In mitigation, David Eager said Warren had now lost his job as he needed a driving licence for his work.
Warren was banned from driving for a year, fined £120, and ordered to pay a total of £119 in court costs and charges.