The A14 was closed in both directions between Kettering and Thrapston after a driver had an apparent medical emergency at the wheel.
Police believe the man’s vehicle came into contact with the central reservation between junctions 10 and 11 after he was suddenly taken ill.
He was driving along the eastbound carriageway shortly after 11am this morning (Monday, November 3).
The air ambulance attended the scene, with the dual carriageway shut between the two junctions, near Burton Latimer and Cranford respectively.
The road was re-opened by 1pm.