Actor Daniel Radcliffe presents an award during the 15th annual Webby Awards in New York June 13, 2011.[Photo/Agencies]?

Harry Potter star Daniel Radcliffe has revealed that he was so worried about his drinking that he vowed to give it up and has become teetotal.

The 21-year-old actor told GQ magazine that his life went off the rails for a time when he turned 18 and was filming "Harry Potter and The Half-Blood Prince."

"I became so reliant on (alcohol) to enjoy stuff," he said in an interview to be published in GQ's August edition. "There were a few years there when I was just so enamored with the idea of living some sort of famous person's lifestyle that really isn't suited to me."

Radcliffe says he was fortunate that the paparazzi never captured his worst behavior.

"I really got away with that because there were many instances when a shot like that could have been taken," he added.

Radcliffe, who says he has not touched a drop of alcohol since August last year, admitted that he would love to be a person that goes to parties and has a couple of drinks but that just doesn't work for him.

"I do that very unsuccessfully. I'd just rather sit at home and read, or talk to somebody that makes me laugh," he added. "There's no shame in enjoying the quiet life."

Radcliffe was just nine when he was picked to star in JK Rowling's Harry Potter series and, according to British press reports, has amassed a fortune of around 45 million pounds ($72 million)

The final Potter film, "Harry Potter And The Deathly Hallows: Part II" has its premiere in London on Thursday and will hit the theatres on July 15.