Raducanu sent the tennis world into a spin when she claimed the U.S. Open title at Flushing Meadows having come through qualifying, not dropping a set in 10 matches.
Since then it has been more of a struggle for the 19-year-old who went out in the first round at the U.S. Open and the second round of the other three Grand Slams and has dropped to 76th in the WTA rankings.
Raducanu has struggled with injuries and has had a succession of changes to her coaching set-up, with Dmitry Tursunov the latest to part ways with the teenager.
"Now I think that she needs to have space and time and talk to people she trusts," King told Reuters ahead of the Billie Jean King Cup Finals which start next week in Glasgow.
"I would hope she has a psychotherapist, I think they're very helpful in hearing yourself. I've been going forever. It really helped my life."
Raducanu's whirlwind rise to fame has inevitably placed high demands on her young shoulders and 12-time Grand Slam singles champion King said choosing the right people to have around is vital for her progress.
"I hope she gets people she can trust, who have no agenda. She needs to get away from people who have agendas, like 'I wanna coach you, I wanna do this' forget that," King said.
"She needs to be herself and she's very bright, actually very level-headed. I'm really impressed with her as a human being."
Raducanu will miss the Billie Jean King Cup because of a wrist injury.
