It averaged 9.4m, or 37.9% of the audience, and peaked at 9.9m or a 44% share. The figure is up 0.4m or 3.1 share points on the opening episode of the last series. Among its target audience of 16- to 34-year-olds the show took a massive 42.4% of the available audience.
An ITV spokesperson said: "We are delighted that almost 10m people tuned into 'I'm a Celebrity... Get Me Out of Here!' last night. It is a fantastic achievement that the series has opened to an even bigger audience than it won last year."
With the cameras barely rolling, ITV looked set to lose its first star, as former 'EastEnders' actor Elaine Lordan, who was taken to hospital just a day into the fifth series.
Lordan, who played Lynne Slater in the BBC soap, was taken to hospital after collapsing twice since arriving in the camp at the weekend. Reports say she is being treated for suspected exhaustion, but that she hopes to return to the show.
A spokesman for ITV said: "As a precaution, Elaine has been taken to hospital for observation following this second incident. A senior member of the production team will be close at hand throughout her stay in hospital and we will be ensuring that she receives the best possible care.
"At this stage, we don't know if she'll be returning to the show."
Meanwhile, bookmakers put fellow 'EastEnders' alumnus Sid Owen, otherwise known as Ricky Butcher, as the favourite to win the fifth series of the reality television series.
Others in the jungle include: former 'Neighbours' star Kimberley Davies; Blue singer Anthony Costa; former Atomic Kitten singer Jenny Frost; Carol Thatcher; Sheree Murphy, who used to be in 'Emmerdale' and is married to Liverpool footballer Harry Kewell; David Dickinson; wine writer Jilly Goolden; and Jimmy Osmond.
Now in its fifth season, 'I'm a Celebrity... Get Me Out of Here!' has been a ratings success for the network, securing an average of 8m viewers an episode and more than 14m for the series finale, when one of the 12 contestants is crowned king or queen of the jungle.
Comedian Joe Pasquale won the last series, while former England cricket player Phil Tufnell and DJ Tony Blackburn have been winners of previous outings.
The series can also claim uniting celebrity magazine favourites Jordan and Peter Andre, who met while starring in the 2004 series.
Bookmaker Paddy Power puts 'Bargain Hunt' presenter Dickinson as the next favourite after Owen, followed by Murphy. Lordan is the outsider, with odds of 33/1.
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