Which statement is the scientific rationale for the combination drug carbidopa/ levodopa (Sinemet) prescribed to a client diagnosed with Parkinson’s disease? 1. The carbidopa delays the breakdown of...

Which statement is the scientific rationale for the combination drug carbidopa/ levodopa (Sinemet) prescribed to a client diagnosed with Parkinson’s disease?

1. The carbidopa delays the breakdown of the levodopa in the periphery so more dopamine gets to the brain. 2. The medication is less expensive when combined, so it is more affordable to clients on a fixed income. 3. The carbidopa breaks down in the periphery and causes vasoconstriction of the blood vessels. 4. Carbidopa increases the action of levodopa on the renal arteries, increasing renal perfusion.