Dr. Drew Pinsky, of VH1's Celebrity Rehab with Dr. Drew, says the answer may depend on how she embraces what he refers to as "the next stage in treatment."
"The way the treatment works is you step down," the TV personality and internist, 52, tells PEOPLE. "You don't go from intensive treatment back to your life, so it's not like it's all over."
For Lohan, 24, or anyone leaving a long stint in rehab, Pinsky recommends taking "the gradual approach" to recovery, which he says requires a few essentials: two to three meetings a day, daily interaction with a sponsor and either regular therapy or an outpatient treatment program.
If he were calling the shots, says Pinksy, Lohan would follow this plan for about a year.
But the reality of the situation, the doctor also says, is sobering. "Even though that's the treatment I would design as an ideal program, very few patients ever take that recommendation," he says. "If they would do it, they would stay sober – but they usually don't."
As Lohan gets back into her routine – squeezing in workouts at the gym and moving next door to ex-girlfriend Samantha Ronson – Pinsky says he thinks the struggling starlet is on-track – although he does have a few words of caution.
"You don't want to return to the same environment you were in and expect the environment to change or you to be able to withstand the effects," he says. "If you're too early to the game, you are very new, and the world will cave in on you if you try to return to the same circumstance."
As for making her way back to the big screen, Pinsky says he would also advise Lohan to take her time. He points to Robert Downey Jr., who made a successful career comeback after struggling with drug abuse throughout the '90s.
"The biggest conundrum for people like [Lohan] is they have real financial concerns and the work beckons, and they make lots of money for lots of people – and those people push on them to return to work," he says. "But the No. 1 reason most celebrity patients relapse is they return to work prematurely."
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