[Arneldo]

BIG Brother sex swapper Nadia put on her old genes for a night down the pub—and was nicked for allegedly belting a BLOKE.

The Portuguese brunette turned man o' war and thumped a 24-year-old drinker after a row, cops were told.

Nadia Almada, 29, was bailed at a north London police station after being quizzed about the incident in a bar in Islington on Thursday.

Now pals are worried what effect it will have on the transsexual celeb who was in the Priory clinic six months ago suffering from depression.

A friend said: "Nadia has a fiery temper and has often had to face hostile people when she is out on the town.

"She's been trying to put her life back on track after a near nervous breakdown, so this is just another thing for her to worry about."

If charged with assault, Big Brother 5 winner Nadia could find herself facing a prison sentence or a hefty fine.

"We are worried about the effect this added stress will have on her," said the pal.

Suicidal

Last September Nadia confessed to the News of the World she hit the bottle after a split with her diamond dealer boyfriend and a disastrous appearance on Australian BB.

She lay in bed at her London home for two weeks on the verge of a nervous breakdown before pals persuaded her to go into the Priory. "I didn't want to live. I felt suicidal," she told us.

Last night a Scotland Yard spokesman said: "We can confirm that on February 16 a 29-year-old woman was arrested on suspicion of common assault on a 24-year-old man in Islington.

"She has been bailed to return to a north London police station in early March."