The man claimed he had been bitten by an adder, the only species of poisonous snake known to live in Sweden, near a children's paddling pool in the Majorna area of central Gothenburg on Thursday.
"It really hurt when it bit me and now I don't feel very well at all," the man told the local Göteborgs Posten daily.
The man's report prompted a hunt for the offending reptile, whose bite can in extreme cases cause death. The hunt was eventually called off later in the afternoon with the snake nowhere to be seen.
Several people have called in reporting that they had seen a snake in the vicinity of the playground in recent days and a reptile expert from the Universum museum has been dispatched to establish the facts.
Despite the reports, Jakob Andreasson at the parks authority in the city however remained sceptical as to whether the normally very placid and shy snake was indeed in the area.
"It could just be one of those rumours which have started and then done the rounds," he said to the newspaper.