Updated: 3:11 p.m.

Former Rep. Charlie Melancon, a moderate Democrat from Louisiana, has left his post as the head lobbyist of the International Franchise Association after just four months at the helm.

He plans to pursue personal business opportunities in Louisiana, according to a statement from the trade association.

“We are extremely grateful for Charlie’s service, counsel and leadership,” Stephen Caldeira, IFA’s president said. “Charlie is a great American who has been an invaluable friend and recognized pro-business leader throughout his impressive career in state and national politics, and we truly wish him all the best with his new ventures.”

Melancon, who joined the group in February after three terms in Congress, never even got the chance to lobby for the franchisees because ethics rules prohibit former Members from lobbying their former colleagues for one year after they leave office.

Melancon served as one of three co-chairmen of the fiscally conservative Blue Dog Coalition and was one of several ex-Blue Dogs who holed up on K Street after the 2010 election devastated their ranks. He decided not to seek re-election to the House last year, running an unsuccessful campaign to oust Sen. David Vitter (R-La.) instead.

He was appointed to the position at the IFA at least in part because he had once been a franchise man himself, owning Baskin-Robbins franchises in Louisiana from 1978 until 1991.

The organization, which represents some 825,000 franchise establishments, seems to have had trouble hanging on to its senior vice president for government relations and public policy. Melancon was appointed in February to replace David French, a longtime lobbyist for the IFA, who held that position for just six months before leaving to become the chief lobbyist at the National Retail Federation.

Judith Thorman, who led the lobbying activities at the American Beverage Association, will replace Melancon starting June 20.

She’s held senior leadership positions in the Washington offices of Gov. Thomas H. Kean of New Jersey (R) and Gov. James R. Thompson of Illinois (R), as well as the Department of Agriculture’s Food and Nutrition Service during the Reagan Administration.

Clarification: June 2, 2011

This story has been updated to clarify that David French lobbied for the IFA before being appointed to the newly created senior vice president job.