Just Eat's executive chairman has taken a leave of absence due to medical reasons.
The FTSE 250 firm said Dr John Hughes will take a leave of absence "in order to undergo treatment for a medical condition".
The food delivery company is in the midst of looking for a new chief executive after David Buttress stepped down in February over "urgent family matters". Both Buttress and Hughes will continue as non-executive directors for the time being.
During Hughes' absence, chief financial officer Paul Harrison will take the reins as interim chief executive and senior independent director Andrew Griffith will act as non-executive chairman.
With the board, they will complete the search for a permanent chief executive.
In a statement Just Eat said: "The board and management team wish John a swift and full recovery, and look forward to his return."
Just Eat delivers food from 68,500 restaurants worldwide, and 27,500 in the UK and has 17.6m customers globally.
Yesterday it was announced that the online food takeaway service had signed a £10m a year deal to be the new sponsor of The X Factor, replacing TalkTalk.
Just Eat said it will launch a nationwide "Chef Factor" search for takeaway cooks to star in its branded clips.
Its sponsorship includes the TV show, app and the annual live tour.