A mum's warning: 'My daughter almost choked on her Fidget Spinner'.

Like many bizarre children’s crazes before them, Fidget Spinners have quickly taken over school playgrounds the world over.

And while teachers are struggling to keep their students from distraction by the insanely popular devices, parents are beginning to worry they could be downright dangerous.

American mum Kelly Rose Joniec was driving her daughter Britton home from swimming on Saturday when she heard an “odd retching noise” coming from the back seat.

“Looking back in the mirror, I saw her face turning red and drool pouring from her mouth – she could utter noises but looked panicked so I immediately pulled over,” Joniec wrote in a Facebook post on Monday.

“She pointed to her throat saying she’d swallowed something.”

Britton explained she had been trying to clean part of her fidget spinner in her mouth and, somehow, swallowed it.

Joniec couldn’t determine if was lodged in her daughter’s windpipe or oesophagus but after the Heimlich manoeuvre failed to dislodge it, resolved to call an ambulance.

At the Texas Children’s Hospital, an X-ray showed the spinner part well and truly stuck in the child’s oesophogas.

It had to be surgically removed.

"Fortunately, we had a positive outcome, but it was pretty scary there for a while," Joniec said.

"[Not] only because of the initial ingestion, but then the concern about the composition and structure of the object, and finally, the risk with general anesthesia."

She then warned other parents to "keep in mind that these present a potential choking hazard".

Listen: Before it was Fidget Spinners, it was Shopkins (post continues after audio...):

Fidget Spinners are actually marketed as learning aids, which is why not all carry the appropriate age warnings one might expect of a children's toy.

They are designed to be held between finger and thumb and spun to use up excess "fidgety" energy.

But far from helping kids concentrate, some schools have resorted to banning the devices for doing the exact opposite.

"It is becoming a problem," Pam Kent, president of the South Australian Primary Principals’ Association, told news.com.au

"Principals feel they are not being used for the intended purpose of being a sensory tool to help kids with their anxiety and help them engage more in their learning."

While occupational therapist Sandra Mortimer confirmed there was "nothing as yet to support this tool as a learning tool".

“A lot of these things and this one in particular, I think, is quite disruptive," she told news.com.au.