Hewitt, who overcame his own alcohol demons after a high-profile incident as a player, told the Herald he had been in touch with Guildford.
He said the contact had been his initiative, but would not comment further, including whether it would be ongoing.
"I'm not going to say any more ... I've been in contact, and that's where I'm leaving it until we get something sorted."
Guildford's agent, Simon Porter, said Hewitt's offer of help was welcome.
"The offers of support and assistance for Zac have come from all quarters. From people who have been through this - and that's from all walks of life."
However, Mr Porter was at pains to stress that the cornerstone of Guildford's treatment would be expert and professional.
"The plan isn't just getting him to talk to people who have done it, or been through similar issues.
"That's part and parcel, but obviously we are relying on some pretty specialist, expert, professional advice on the way forward."
Yesterday, Guildford's housemate and friend Stu Bailey thought the offer of help from Hewitt was "fantastic".
"The people who have been through these things themselves are obviously the best people to offer advice," said the 43-year-old bookmaker with the TAB.
Guildford, who has played 10 tests for the All Blacks, has withdrawn indefinitely from the Crusaders for this year's Super rugby season following an incident at a party at a Christchurch house on January 12.
He allegedly punched another party-goer while drunk.
Hewitt, a former All Black hooker, drunkenly broke into the wrong Queenstown hotel room in 1999.
His actions at the time made national news, and he broke down at a press conference organised by the NZRU to apologise for his actions.
It proved to be a life-changing moment, with Hewitt finally realising the extent of his drinking problem.
Yesterday, Mr Bailey said Hewitt's contact was indicative of the strong support for Guildford.
"I'm sure he's going to come out of it an even better person."
Mr Bailey also felt Guildford could take heart from the turnaround of another embattled Kiwi sports star, cricketer Jesse Ryder.
"Zac [knows] Jesse and I'm sure Jesse will offer his support if he hasn't already," Mr Bailey said.
"Jesse is a real example of how you can better yourself.
"He's another sportsman with a terrific amount of ability.
"And if you take the complications out of his life, then you see the benefits of that - he's probably never played better cricket than he is right now."
- Nicholas Jones and Kurt Bayer
