The centre-back, who last played for the Seasiders just under a month ago, said that he wouldn't wish the problem on anyone and is now back to full fitness after doing a sponsored eat to regain the weight that he lost.
"I'm feeling more human again," Clarke told the club website. "It turned out to be a twisted colon, which I wouldn't really wish on anyone.
"Thankfully I saw the right people and got the right treatment."
Clarke, 32, left Huddersfield for Blackpool this summer after five years with the Terriers.