Man, 73, issues warning after suspected spider bite left him unable to walk a month later

A British man has shared a harrowing warning after a spider bite left his leg swelling to the 'size of a large watermelon'.

Glenn Priestly appeared on ITV's Good Morning Britain earlier this week, where he revealed he had been renovating his mother's home when he was bitten by the 'unusual' spider.

Though the 73-year-old says the bite on his leg was not painful at first, over the course of a few hours his limb began to swell at an alarming rate.

The irritation eventually led to him going to get checked out at hospital, where he ended up being admitted for several days.

It's believed he was bitten by a noble false widow spider (PASCAL PAVANI/AFP via Getty Images)

Recalling the events of September 16, Priestley said: "I got back to the house late that night and had a pain in the leg, pulled up my trouser leg to find it had blown up in size and it was rosy, deep red.

"On the 16th, 17th, 18th, it was rosy red, then on the 25th it was gory. On the 28th it started to wither, but the pain was so excruciating that I couldn’t put my leg down."

He explained to the hosts he had been doing work at his mom's house in Blackpool, Lancashire, when he noticed seeing a 'dark brownish' spider, unlike any house spider he'd seen before, coming down a wall.

"It was completely alien to me," he said of the spider, which is now believed to have been a noble false widow spider, a distant relative of the black widow, dubbed as Britain's most venomous spider.

Priestley revealed he believes the eight-legged beast was lurking in a blanket that had fallen to the floor, which he later covered himself with.

Speaking to the BBC, the 73-year-old later revealed the pain that ensued in the days after the bite.

"I didn’t think much of it at the time, but a day or so later I experienced a rapidly increasing pain in my leg and discovered it was swollen and highly inflamed and hot to the touch," he explained.

"I went to the doctors the next day and they saw how bad it looked and rushed through blood tests. A day later I was at Blackpool Victoria’s medical assessment unit and ended up staying in hospital for four days."

More than a month later, Priestly is still having to keep bandages on the wound and use a walker because his the leg is 'too painful to walk on'.

He went on to explain to the Blackpoll Gazette that he'd describe the pain as being 'on a level of nought to ten, I'd give the pain an eight'.

“It’s been a pretty alarming and unpleasant experience,” Priestley added. “The pain has been really intense. I’d advise anyone else who has a suspected spider bite and starts to feel serious pain to get it checked out right away.”