The 27-year-old, who recently arrived back on Teesside after a spell with Ajax, will spend the remainder of the campaign back in his native country.
Mido trained briefly with the club he joined in a ?6million switch from Tottenham in August 2007 after leaving Ajax amid confusion over who he actually belonged to.
But he is now heading home to see out the final few months of his four-year contract.
Meanwhile, fellow striker Lee Miller, 27, will spend the rest of the season on loan to Boro's npower Championship rivals Scunthorpe after struggling to make his mark in the north-east.
Source: PA
Source: PA