Back on March 18, Lindsay Lohan finally took a plea deal for a lockdown rehab facility in her lying to the cops case. But she had one condition: She wanted permission to take Adderall while she's drying out.

Sources for TMZ say La Lohan has been using the drug for years and is convinced she needs it to function.

Interestingly enough, she was first prescribed the medicine (used to treat ADHD, attention deficit-hyperactivity disorder) while behind bars back in 2010, which caused all sorts of controversy.

For her recent plea deal, LiLo said she wanted to take her Adderall while in rehab, or she'd take her chances with a trial. At the time, lawyer Mark Heller assured her she would be able to hold onto her prescription security blanket while she's in her court-mandated lockdown rehab. Despite, you know, not being eligible for the few lockdown rehabs that actually exist.

Ironically, we could use a little Adderall ourselves to help keep track of the increasingly confusing details of this mess.

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