Which medication is a standard treatment for Parkinson's disease?

• A. Coenzyme Q10
• B. Levetiracetam
• C. L-dopa
• D. Fluoxetine

Answer: (C)

In Parkinson's disease, addressing the loss of dopamine in the brain is the primary treatment goal. L-dopa is a dopamine precursor that crosses the blood–brain barrier and is converted into dopamine in the brain, directly replenishing the depleted neurotransmitter. This makes it the standard, most effective therapy for improving motor symptoms such as slowness, stiffness, and tremor. It’s typically given with carbidopa to prevent peripheral breakdown, which increases brain delivery and reduces side effects. The other options do not target the core dopaminergic deficit in the same proven way: coenzyme Q10 lacks consistent evidence as a standard treatment; levetiracetam is used for seizures; fluoxetine is an antidepressant.