An overturned lorry that became stuck on the central reservation caused the A14 at Bury St Edmunds to be closed for about eight hours.
Emergency services attended the scene by the British Sugar factory after the incident, which happened at 03:37 GMT, according to Suffolk Police.
The lorry driver has been taken to hospital with serious injuries.
The road between junctions 43 for the town and junction 42 for Westley, re-opened at about 11:40.
Essential repairs to the central reservation took place, said Highways England.