'I think it's time for another B52,' says bleary-eyed Natalie, holding on to a pillar to keep herself upright while she tries to locate her friends.
Amy is sitting on the sticky dance floor using a felt-tip to write her phone number on a man's hand. She is laughing because she can't remember what it is. Molly is laughing because Amy is sitting on the floor, oblivious to the fact that she herself is staggering around the club, tripping up on her stilettos and falling into people.
Another B52 (a potent combination of Tia Maria, Cointreau and Baileys in a large shot glass) is the last thing Natalie needs. It will probably send her on a bee-line for the toilets, but she seems determined to do it.
It is 1am on Saturday and the girls are in a nightclub in north London. A throng of bodies is leaping around to chart music. Men are making circles, putting their arms around each other and kicking their legs into the air. Others are trying to dance up towards groups of girls, and couples are forming in the corners.
The bar is packed, and along it are lines of shots, alcopops and pints. Close by, a girl in a short denim skirt with a tight, backless top is drawing the attention of a group of men.
She is on her knees with her head tipped back and mouth wide open. One of the men lights a match and puts it towards her mouth. It glows a blue colour before she shuts it and hangs her head forward. 'Flaming Sambuka,' says Natalie with a smile. 'Let's do one.'
Five hours, a gin and tonic, a B52, one cocktail, four alcopops, a shot of tequila, three glasses of wine (at least 17 units of alcohol) and £30 earlier, Natalie was at her friend Amy's house getting ready for a night out. They were celebrating the fact that it was ... Friday night.
Dressed in fitted jeans with rock-chick belt, a pink, low-cut polka dot top and a white cardigan with a huge furry collar, she picked up her first glass of wine with one hand and began to apply nail varnish to her toes with the other. As a 23-year-old solicitor, she thinks she deserves to have fun. 'I have worked hard all week, and tonight I am going to let my hair down.'
Natalie is part of a growing army of women who are causing alarm bells to ring in Whitehall. It is estimated that almost one in four women now drink more than the recommended daily alcohol limit of three units at least once a week. In addition, one in 10 women now 'binge drink' - that is to say they consume six units of alcohol in one session (equivalent to two thirds of a bottle of wine) - once every week.
It is a trend that has worrying repercussions for the UK economy. So concerned is the Government that it has charged the No 10 Strategy Unit with drawing up a range of new policies to target excessive drinking and combat alcoholism.
The results will be published early in the New Year, but according to the Strategy Unit's interim report, published in September, alcohol misuse now costs the NHS up to £1.7 billion a year. In addition, UK plc loses £6.4bn in lost productivity while the cost in related crime and public disorder is estimated to be up to £7.3bn.
It is female drinkers who are causing the Government most alarm. The Strategy Unit's report states: 'The prevalence of drinking in excess of the weekly recommended limits has increased in both sexes and in most age groups from age 16 onwards. This increase has been most marked in those aged 16-24, particularly women.'
In the nightclub Natalie went to this weekend the women were oblivious to such concerns. Most looked like they were just having fun with their friends. There would be a few regrets in the morning, some funny stories and a lot of sore heads - but the girls consider the amount they drink to be normal.
Molly, a 21-year-old student, is shocked at the suggestion that she is a binge drinker: 'Having three glasses of wine in a night more than about four or five times a month counts as binge drinking? That is not binge drinking. That's called having a social life. A little alcohol lightens you up. Obviously there are those who take it too far, and they should be specifically targeted rather than heaping stigmas on normal girls who are just want to have a laugh - like their male counterparts.'
The others agree. They think that if the categorisation of binge drinking was more realistic, then those with a problem would realise it. 'At the moment they probably dismiss it as something that a stuffy-nosed, teetotal, Mary Whitehouse type came up with,' said Amy.
The girls' attitude to drink is shared by thousands of others in their age group. They want to have fun, feel they do it in moderation, and say it is the Government which has got it wrong, not them. But they are interested to hear that women before them were not such big drinkers. 'The market does seem to be aimed at girls,' says Natalie as she picks up an alcopop. 'Look at the packaging - the colours are girly, and they are in bottles which make them good for dancing. There are also so many more cocktails, spirits and wines now. In the past it was just beer.'
And they welcome the change, saying it means they can now do what men have always done. Their biggest worry about drinking is what they might end up doing on the night, not the state of their liver. Amy admits that she has slept with men and been barely able to remember it, and Molly has found herself unable to get home by herself. The solution, they say, is not to drink less but to make sure they are always together.
For others, the hedonism they experienced in their late teens and early twenties has led to bigger problems. Sarah, 24, has just moved to Manchester after studying in Dublin. At university she and her friends drank nearly every day. On Friday she went to a dinner party armed with half a bottle of vodka and a bottle of absinthe. 'It was embarrassing,' she says. 'I could barely talk.'
On a normal night out Sarah will drink half a bottle of vodka before she even leaves her house. After that she will drink vodka with coke, orange or lemonade. Sometimes she will drink pints and on special occasions she will drink a 'turbo shandy' - two-thirds of a pint of beer with a double vodka and topped with an alcopop.
'According to my friends I am not that big a drinker,' she says. 'I think it is sad that so many people binge-drink. Some of my friends who had so much fun at university are now alcoholics and they are unable to hold down a job or a relationship.
'But what do we achieve from the knowledge that British girls are the biggest binge-drinkers - of course they are, it is such a socially acceptable drug here. I think the bigger question is why do people feel the need to do it. Is everyone that messed up that they need to be off their heads all the time?'
It is a question being asked with ever greater urgency by alcohol concern groups who point out the number of women drinking to excess will outnumber men within the next 10 years. 'Male and female levels of excessive drinking have been converging, largely as a result of increased levels of drinking by women,' the Strategy Unit's interim report concludes. 'If the trends since 1993/94 are simply extrapolated over the next decade, then the prevalence of drinking above the weekly recommended limits among young women will total 53 per cent compared with 48 per cent of men by 2012.'
The Government finds itself in a tricky position. Attempts to lecture women will see Ministers branded killjoys. 'The Government is very nervous about being seen to preside over a nanny state,' said Eric Appleby, chief executive of Alcohol Concern.
The Government is also all too aware that the drinks industry generates £7bn a year for the Exchequer: attempts to change the UK's drinking habits could seriously hurt the Treasury.
One solution currently being discussed is to force the drinks industry to play a greater role in tackling the problem. Critics of the industry point out that it spends billions a year marketing its products but does little to contribute to alcohol awareness campaigns. Diageo, for example, recently spent £250m on rebranding the young woman's tipple of choice, Smirnoff Ice.
The Government's Big Conversation website poses the question: 'Is there a case for a levy on alcohol advertising, with the proceeds ploughed back into treatment and into advertising campaigns promoting responsible drinking by young people?'
Ten years ago the Government posing such a question in public would have been unthinkable. It is a sign of how serious the problem has become that the matter is being discussed at all.
