The crash happened at about 08:00 near Whitburn in West Lothian.
The drivers sustained minor injuries, Police Scotland said.
Traffic was backed up between junctions four and five eastbound, causing long delays. The route was fully reopened after more than two hours.
The Scottish Fire and Rescue Service cut one of the drivers free from a Peugeot van.
The drivers are being treated at Wishaw General Hospital.
Four drivers are being treated in hospital after being injured in a crash involving three lorries and a van on the M8.