Kendall Jenner was reportedly "hospitalised" for a reaction to a 'vitamin infusion.' But what is it?

Let’s take a little trip back to 2012, when vitamin infusions were a thing. Everyone from Rihanna to Madonna was being hooked up to IV drips for a quick energy boost. But just as quickly as the trend emerged, it seemed to have disappeared. Until now.

According to website The Blast, Kendall Jenner needed to be hospitalised before the Oscars on Sunday after receiving – you guessed it – a vitamin infusion.

Kendall, 22, apparently had an allergic reaction to the infusion, which landed her in Cedars-Sinai Medical Center in Beverly Hills. She made a quick recovery though, and was out in time to attend the Vanity Fair Oscars party later that night.

Although not talked about much anymore, vitamin infusions have clearly had a lasting impact in Hollywood, becoming a standard part of the prep work for celebrities who are about to step out at a big event. So what the hell are they and what do they actually do?

Well, basically it's a quick and intense way to get the most out of your vitamins, through an IV drip. According to website Live Science, people have reported feeling more "alive" after getting a vitamin infusion.

Several vitamin infusion companies have been set up to accommodate people who are fans of getting the good stuff pumped straight into their veins.

But while it may be great for a quick fix, a lot of health professionals are wary, saying it could create an imbalance with your body's natural antibodies.

"The mistake is assuming something that feels good in the short term is necessarily good for you in the long term," US-based doctor David Katz told Shape.

Users of vitamin infusions may also be more prone to infections, and in the alleged case of Kendall, allergic reactions.

"Since you’re bypassing natural defence organs, like the liver, you’re also more at risk for allergic reactions if the ingredients aren’t well regulated or monitored," US-based pharmacist Sonia Patel told Teen Vogue.

"While rare, these reactions can happen if your drip contains harmful additives, herbs, or a nutrient dose that’s too high."

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So, in general, most health professionals agree you should concentrate on your overall well-being before you decide to do anything drastic, like stick an IV drip into your vein.

"If you need to feel better, identify why you’re not feeling well, whether it’s poor diet, not enough exercise, too much alcohol, dehydration, lack of sleep, or too much stress, and address it at its origins in order to experience a long-lasting meaningful benefit," added Dr Katz.