Which medication is used to increase the level of dopamine in patients with Parkinson's disease?

Which medication is used to increase the level of dopamine in patients with Parkinson's disease?

• A. Sinemet (carbidopa-levodopa)
• B. Levodopa alone
• C. Selegiline
• D. Bromocriptine

Answer: (A)

In Parkinson's disease the goal is to restore dopamine signaling in the brain by increasing the amount of dopamine available where it’s needed. Levodopa is a precursor that crosses the blood–brain barrier and is then converted into dopamine inside the CNS, helping to replenish depleted dopamine stores. Carbidopa is added to levodopa (as sinemet) to block its conversion to dopamine in the periphery. This keeps more levodopa reaching the brain and reduces peripheral side effects like nausea. So, this combination provides the most effective way to raise brain dopamine levels and improve motor symptoms. Other options don’t increase brain dopamine levels in the same way: selegiline inhibits breakdown of dopamine but doesn’t supply more dopamine, bromocriptine directly stimulates dopamine receptors without raising overall brain dopamine, and levodopa alone lacks the peripheral protection that carbidopa provides, leading to more side effects and less CNS delivery.

In Parkinson's disease the goal is to restore dopamine signaling in the brain by increasing the amount of dopamine available where it’s needed. Levodopa is a precursor that crosses the blood–brain barrier and is then converted into dopamine inside the CNS, helping to replenish depleted dopamine stores. Carbidopa is added to levodopa (as sinemet) to block its conversion to dopamine in the periphery. This keeps more levodopa reaching the brain and reduces peripheral side effects like nausea. So, this combination provides the most effective way to raise brain dopamine levels and improve motor symptoms.

Other options don’t increase brain dopamine levels in the same way: selegiline inhibits breakdown of dopamine but doesn’t supply more dopamine, bromocriptine directly stimulates dopamine receptors without raising overall brain dopamine, and levodopa alone lacks the peripheral protection that carbidopa provides, leading to more side effects and less CNS delivery.