A MAN caught driving with ketamine in his system did not understand how long the drug would remain in his blood, a court heard.

Daniel Daley, 20, of Tuffley Crescent, pleaded guilty to drug driving at Hereford Magistrates Court last week.

Owen Beale, prosecuting, said it was on June 13 that police officers decided to follow Daley in an unmarked vehicle when they saw him driving along Edgar Street.

After he went through a red light at a set of temporary traffic lights officers stopped the vehicle and conducted a drug swipe which was positive.

At the police station, a blood sample was taken which gave a reading of 82mg of ketamine per litre of blood. The legal limit is 20mg.

Chris Read, defending, said Daley simply did not understand drugs of this type could remain in an individual's system for some time after taking them and he thought the effects would have been over.

"He was very clear he didn't feel in any way impaired," he said, adding the conviction would cost him his job.

Magistrates disqualified Daley from driving for 12 months and issued a fine of £110, ordered him to pay £135 costs and a £30 victim surcharge.