He’s a Louisiana-hoodoo man, a jittery gris-gris doctor prescribing syncopated second-line fonk (his idiosyncratic funk) as a cure for his patients. After years of gigging around the city as a studio musician, New Orleans guitarist turned pianist Mac Rebennack adopted the Dr. John persona in 1968.

Not everybody was impressed with the good doctor’s first prescription, 1968’s Gris Gris. “What is this shit?” Rebennack remembers Atlantic records head Ahmet Ertegun yelling when he stopped by a Bobby Darin session Rebennack was working on to vent his anger after hearing the record for the first time. Ertegun described Dr. John’s initial output as “a boogalee coonass record. ” Even Rebennack’s colleague Harold Batiste thought it might “slot off into the psychedelical market.”

“It didn’t go that way,” Rebennack says of the record that established his career and became a cult classic. “And that’s why life is inarrestin’ and full of surprises, and shit happens.”

Rebennack built up the Dr. John persona with a string of psychedelic, swampy records in the ’70s: Babylon,Remedies and The Sun, Moon & Herbs. But with 1972’s Gumbo, and again with 1973’s In the Right Place, Rebennack reached back in his trick bag and brought out the real spirit of New Orleans.

“I try to make records that are true,” the pianist says. “From the heart, you know.”

He’s continued that quest on his own with records like 2002’s Creole Moon and N’Awlinz: Dis Dat or D’Udda and with others’ work, including Shemekia Copeland’s Talking to Strangers.Dr. John produced, played on and toured for that record.

Although his music epitomizes the spirit of the Crescent City, Rebennack, who now resides in upstate New York, has not lived there for some time. When he got busted in ’63 and served two years in a federal prison in Fort Worth for charges that revolved around a shooting, a heroin addiction and financial trouble, he was given papers telling him not to come back, he says. But in another version, he says he gave up his house to an ex-wife–and just kept on going.

No matter where he is physically, Rebennack’s spirit is still in New Orleans. He’s long been critical of New Orleans politicians for not doing more to promote local music and provide additional venues, but he continues to support those who try to make a living there.

“I’m real proud of all my homies that makes gigs outta nothin’, outta funny venues,” he says.

To help those homies in need because of Hurricane Katrina, Rebennack participated in two musical relief efforts. The New Orleans Social Club–members of the Meters, the Nevilles and friends including Dr. John and Irma Thomas–recorded Sing Me Back Home, to be released April 4. Dr. John contributed a version of Fats Domino’s “Walking to New Orleans.”

Dr. John also recorded Sippiana Hericane, a nine-track tribute to the Crescent City in the wake of the hurricane as well as a plea for good sense in managing the environment. (“Clean all the waters in the world,” the Doctor urges on “Clean Water.”) All net profits from the sale of the record go to relief organizations.

And, for his own edification, Dr. John has just recorded Mercerized: The Songs of Johnny Mercer, out May 23 on Blue Note. It includes covers of Mercer’s hits “Moon River” and “Ol’ Black Magic.” If you thought the Doctor had lost his focus or his fonk, though, he’s included his own contribution: “I Ain’t No Johnny Mercer.”

That’s a fitting concept for a legend who insists that, when his rounds are over, he only wants to be remembered for one thing–“Just some guy that showed up for all the gigs.” x

Dr. John and his band the Lower 911 play The ArtsCenter in Carrboro on Thursday, March 2 at 7 and 9:30 p.m. Tickets are $39.