A teacher who crashed her car while brushing her teeth told police she had lost concentration.

Cherie Margaret Davis, 65, who was treated at Blenheim Hospital for her injuries after a crash on March 19, had also been drinking, Blenheim District Court was told yesterday.

Sergeant Graham Single said Davis was driving toward Picton when she set the cruise control of her car at 100km/h, "got out her toothbrush and started brushing her teeth".

After veering to the left, she over-corrected and crashed into a rock bank on the right side of the road, The Marlborough Express reported.

Her blood alcohol level was 135mg. The legal limit is 80mg.

Davis had also been found drink-driving on March 13 when her car drifted to the left and collided with another vehicle.

She did not stop and another driver called the police to report a car "driving all over the road".

Police eventually found Davis at a Renwick house and she later admitted she had been drinking during the day.

Her blood alcohol level was 149mg. Davis admitted two charges of drink-driving, two of careless use and one of driving while prohibited.

She told Judge Carrie Wainwright her teaching job at Christchurch Polytechnic Institute of Technology had "more or less gone" after the earthquake and she had been upset at the time about family problems.

Judge Wainwright remanded Davis until May 9 for sentencing.