More than 2,000 copies are believed to have been made available in the UK, a sizable increase from the 30 or so copies usually sold each week.
Demand has been high for the issue in the wake of the deadly attack on the magazine's office in Paris on January 7 that killed 12 people.
Five million copies of the magazine -- which usually has a print run of around 60,000 -- were published in a special edition commemorating the Paris massacre.
Interest in the magazine had prompted more than 50 British Muslim leaders to appeal for calm from Muslims in response to the front-cover cartoon earlier this week.