Greg Rutherford rushed to hospital after allergic reaction

The athlete, 36, suffered a "sudden" reaction to an unknown substance earlier this week and has since taken to social media to update fans on the "horrible" experience.

Rutherford, who represented Great Britain at the Olympics, took to his Instagram story: "I suddenly had a massive allergic reaction to something (no idea what) and had to get Susie to rush me to hospital.

"Thankfully they pumped me with a load of stuff and calmed it down. But it was HORRIBLE.

"This rash was covering my entire body. I’m not home. A little [itchy] still, but nothing like earlier. I was trying to get my skin off it was so bad.

Greg Rutherford suffered a 'sudden' reaction to an unknown substance. ( Bang Showbiz/ Greg Rutherford) (Image: Bang Showbiz/ Greg Rutherford)

Greg Rutherford shares health update on Instagram

"I’m going to get some tests done to figure out what it was, as I NEVER want to experience that again.

"I was screaming at one point… So apologies for that too. (sic)"

The sportsman later shared a further update with fans where he explained that he now just needs to figure out what caused the reaction in the first place and "wouldn't wish" such a "horrific" ordeal on anyone.

He said: "I'm much better today. I still have itches on my skin but nothing like yesterday, which is great. I got some stronger antihistamines just in case it happens again.

"It's now going to be a case of figuring out what it was and hopefully it will never happen again. It was horrific and I wouldn't wish it anyone!"

The former Celebrity MasterChef winner had to be driven to hospital on Sunday, August 6 when his partner arrived home to find him "screaming in pain" after the mystery condition left him suddenly "clawing" at his skin.

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His partner of over a decade, Susie Verrill, wrote on Instagram: "Ran in the house, found @gregjrutherford there again, screaming. Acting like one of those people you see in videos where they've taken bath salts.

"He was clawing at his skin and just screaming. Repeatedly. He ran to our car and while I rang 999 again to say I'd have to take him.

"We had to run every red light and I had to focus on not crashing while he screamed and tried to grab the wheel. He was delirious and I looked like I was kidnapping him.

"I was on the phone to the 999 call handler and the poor girl just kept saying 'ok yeah he doesn't sound good, please be safe but hurry' and I was like ok well this is a nightmare because I've been driving like 3 months.

"It was AWFUL. I was just waiting for him to stop breathing while also trying not to crash (sic)"