A fad that started in Hollywood and expanded to the wider population involves an unusual way to get nutrition.

Exhausted Americans are going to private clinics on their lunch breaks to get an IV drip of what some claim is an energy-boosting cocktail.

"It's really like a multivitamin in a bag," said Dr. Jeffrey Morrison, director of the Morrison Center, an integrative medicine center in New York City. "This is a way to give much more high concentrations of vitamins, minerals and antioxidants so the body has all the building blocks so it can heal itself and respond to the stresses of day-to-day life."

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Another doctor, Karima Hirani, of Culver City, Calif., said her liquid vitamin patients suffer from a range of conditions such as chronic fatigue, depression and anxiety.

Stars such as Madonna, Simon Cowell and Cindy Crawford reportedly are on the liquid vitamin bandwagon, and a photo Rihanna tweeted of herself with an IV needle in her arm last year fueled speculation that she, too, enjoys the so-called "party girl drip" treatment.

The treatment is not just for stars. Christina Andrews recently had an infusion of vitamins B5 and B12.

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"I'm on my feet 12 hours, so I need a lot of energy," Andrews said. "I recommend it to all my friends."

Music executive Carmen Key gets her drip at a Los Angeles clinic once a week.

"Instead of feeling, like, energized, you feel alive," she said.

Asked whether she couldn't get the same feeling from eating a proper meal, taking vitamins and a having long nap, Key replied: "Yeah. That probably would do 4 percent of what this does."

But not everyone's a fan.

Critics say the practice is extreme and unnecessary, and question whether is offers anything that can't be had from vitamins and nutritious food.

And the treatments don't come cheap. Each session can cost between $130 to $275.