TMZ has learned ... Lindsay Lohan can still take two drugs, in spite of Judge Marsha Revel's drug testing requirement -- and one of the drugs could be at the root of Lindsay's problem.
Sources tell us Lindsay has prescriptions for Adderall (a stimulant that treats ADHD) and Ambien. Under the rules of the drug testing program, Lindsay can still take meds, provided they were prescribed by a doctor.
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