The extra game-time is opportune for Parkinson, who was surplus to international requirements this winter and was also overlooked in last month's Hundred draft. He has featured 12 times for England across formats, including a solitary Test appearance against New Zealand at Lord's last summer, when he was called up as a concussion substitute for Jack Leach.
"Following conversations between Matt and the club's coaching staff, it was agreed that game time in the County Championship would be preferable," Mark Chilton, Lancashire director of cricket performance, said.
"Earlier this week, an opportunity arose for Matt to join Durham on loan and the deal has been agreed between both counties and the player.
"This is a great opportunity for him to get some more overs under his belt in a more competitive environment. We are looking forward to seeing how he performs and to welcoming him back into the squad."
Kuhnemann had himself replaced fellow Australian Todd Murphy at Durham, but was unable to take the field on the final day of their drawn match against Durham after suffering a back problem, and will continue to be assessed by the club's medical staff.
Parkinson's two-week stint covers a solitary Championship game. Durham are one of ten teams in action this week, with Lancashire sitting out the round prior to their match against Nottinghamshire starting at Trent Bridge on May 4, for which he will now be ineligible.