A mum's snot clearing hack is going viral. But an Aussie doctor has an important warning.

It’s weirdly fascinating to watch, but please don’t try this at home.

A mother’s gross-looking trick for unblocking her young daughter’s nose has gone viral. But Melbourne GP Dr Tony Bartone warns that parents who try it at home run the risk of their child choking.

In a video posted online, the unidentified mum can be seen squirting a syringe full of salty water up the little girl’s right nostril. Immediately, greenish-looking mucus comes streaming out of the other nostril.

The mum repeats the process a few more times, producing an unbelievable amount of mucus, which she wipes away. The little girl looks pretty happy about it all.

In just over a week, the video has been watched by more than 20 million people and racked up more than 60,000 comments. People are fascinated by it.

“This is pretty damn gross, but there’s also something oddly satisfying about watching this poor little baby getting her nose cleared out,” comments one person.

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Several parents say they’re going to try it at home.

“So gonna do this when Joey has a blocked nose,” one writes.

“I’ll have to try this next time on Evie,” another adds.

However, Dr Bartone, who is vice president of the Australian Medical Association, says parents of young children with stuffed-up noses should “absolutely not” be copying what the mother does in the video.

He says the technique, known as nasal irrigation or nasal flushing, is used for some conditions, such as chronic sinusitis. However, it should only be used on young children under the guidance of a medically trained professional.

“It has a place to play in the management of certain medical conditions but it’s certainly fraught with danger if you’re using it without proper instruction and counselling from the appropriate doctor or healthcare professional,” he tells Mamamia.

“It’s something I wouldn’t recommend at all as a routine by parents.”

Dr Bartone says nasal sprays or nasal drops, given under the guidance of a health professional, would be much more appropriate for children this age than nasal flushing.

“Certainly I would be extremely worried that this practice would take off as a suitable option for the average person out there without any formal supervision or advice, in terms of risks and complications.”

He says if parents try the technique on their children, it could have unintended consequences.

“Even aspiration – when the water goes down the back of the nose, into the throat and then potentially into the airways, causing the child to choke. That’s unlikely, but it’s a possibility.”