Britney Spears' biggest hit, Toxic, had a very familiar inspiration (Photo: Rex/ Record Plant Studios)

There is no denying that Toxic is one of the Britney Spears' biggest hits of her career, but some fans are only now realizing the very familiar influence behind the track.

The 42-year-old singer released the single two decades ago and it's been stuck in our heads ever since.

It has become musical folklore that the bop, written by a team including Cathy Dennis, was actually inspired by BBC star and Supervet presenter Noel Fitzpatrick.

Jason Pargin decided to surprise us once again on TikTok, investigating the story behind one of the pop legend's biggest hits.

“Here are some silly musical facts that might change the way you think about this song forever,” the John Dies At The End author began, before clarifying the lyrics.

“I'm not kidding when I say that the man described in that song is supposedly Irish veterinarian Noel Fitzpatrick.

'He is currently the presenter of a BBC veterinary reality show called Supervet.'

“Remember, she didn't write this song,” Jason emphasized. 'Toxic was written by a team that included Cathy Dennis. She also wrote Can't Get You Out of My Head for Kylie Minogue and I Kissed A Girl for Katy Perry.

'She was the one who, in the early 2000s, dated Fitzpatrick when he was just a vet and an aspiring actor. They had what was apparently a nasty breakup and she immediately wrote the song Toxic.

Dr Noel Fitzpatrick

Fans think the cheeky track is about super vet Noel Fitzpatrick (Photo: Getty Images)

The track first blessed our ears in 2003 and instantly reached number one across the world, including in Australia, Canada, the US and the UK.

It was co-written by Cathy, who put the song's lyrics to paper the same year she broke up with the country's most popular vet.

Social media has already come alive with comments on the speculative information, as Twitter account PopB***h said: 'The man who inspired Britney Spears' track Toxic was someone the song's co-writer Cathy Dennis was dating in the early 2000s, which ended with her in 2003: Noel Fitzpatrick.

'It's unlikely you knew who he was at the time (unless you had a sick spaniel), but he's better known to most people these days as Channel 4's Supervet!'

However, this is also not the first time the idea has been floated, with the famous vet previously quizzed about her potential muse qualities whilst appearing on This Morning.

Holly Willoughby asked the vet if he had anything to do with the lyrics that say, 'I need a dose, baby, give it to me. You're dangerous, I'm loving it.

Britney Spears

Britney released Toxic in 2003 and immediately topped the charts (Photo: Getty)

She was talking to him via video link when she said: 'Is this the song written about you? And you? Please say yes.'

Noel replied: 'Maybe you need to ask Kylie Minogue if I Can't Get You Out Of My Head is written about me.'

Cathy has also written songs for S Club 7, including Reach, and Come into My World for Kylie, as well as Can't Get You Out of My Head.

Kylie reportedly turned down Toxic before Britney got her hands on it — and the rest is music history.

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