Heikki Kovalainen has been ordered to bed for a few days to nurse "heavy concussion" sustained at the weekend in Germany.
After clipping a wall, the Lotus driver crashed at the start of the Race of Champions evening in Dusseldorf when the throttle of his Audi R8 stuck open.
Finn Kovalainen, 29, was knocked unconscious for 30 seconds and sent to hospital for checks.
He then had some more checks in Switzerland on Monday and confirmed that he was "put to bed at home as a precaution" due to "heavy concussion" and a headache.
Kovalainen wrote on Twitter that he will have more tests in the next few days "as (my) head took a big hit".
His girlfriend and passenger Catherine Hyde was also injured in the crash, confirming a hairline fracture of her pelvis and hip, and damaged leg muscles.
"Both of us (are) on bed rest for a while," she said.