Which option lists a standard combination used to treat Parkinson's disease?

Which option lists a standard combination used to treat Parkinson's disease?

• A. Insulin
• B. Antidepressants
• C. Levodopa
• D. Levodopa with Carbidopa

Answer: (D)

Parkinson’s symptoms come from a shortage of dopamine in the brain, so replenishing that dopamine is a primary treatment goal. Levodopa is the usual starting medication because it is a precursor that crosses into the brain and is then converted to dopamine, helping to improve motor function. Adding carbidopa makes this approach much more effective. Carbidopa blocks the enzyme that converts levodopa to dopamine outside the brain, which lowers peripheral side effects like nausea and vomiting and allows more levodopa to reach the brain. This combination—levodopa with carbidopa—is the standard, most commonly used regimen for treating Parkinson’s disease. Other options listed are for entirely different conditions (insulin for diabetes, antidepressants for mood disorders) and do not address the dopamine deficiency central to PD, so they are not the standard treatment in this context.

Parkinson’s symptoms come from a shortage of dopamine in the brain, so replenishing that dopamine is a primary treatment goal. Levodopa is the usual starting medication because it is a precursor that crosses into the brain and is then converted to dopamine, helping to improve motor function.

Adding carbidopa makes this approach much more effective. Carbidopa blocks the enzyme that converts levodopa to dopamine outside the brain, which lowers peripheral side effects like nausea and vomiting and allows more levodopa to reach the brain. This combination—levodopa with carbidopa—is the standard, most commonly used regimen for treating Parkinson’s disease.

Other options listed are for entirely different conditions (insulin for diabetes, antidepressants for mood disorders) and do not address the dopamine deficiency central to PD, so they are not the standard treatment in this context.