Possible Clues:

• L-___
• L-___ (Parkinson's treatment)
• L-___ (drug used in Parkinson's treatment)
• Amino acid formed in the liver
• L- -- (drug treating Parkinson's)
• L-___ (treatment for Parkinson's)
• L-__: Parkinson's treatment
• L- -- (Parkinson's treatment)
• Parkinson's drug
• L-___ (treatment for parkinsonism)