Brief Answer:
incomplete control of symptoms

Detailed Answer:
Hello and thank you for your question.
Sinemet is a combination of levodopa and carbidopa that is used to treat Parkinson's disease.
Many of the primary movement symptoms can be improved with sinemet if it is started early in the course of the disease and if the dose is sufficient.
The levodopa is the active component and the carbidopa helps the levodopa cross the blood brain barrier and be active in the brain where it is needed and to prevent the levodopa from being converted to dopamine before it gets to the brain. If this happens there can be side effects of nausea, vomiting and dizziness.
If there is insufficient carbidopa, then the above side effects can occur.
If the levodopa dose is not sufficient, sinemet will not be as effective as it might be in managing the symptoms of bradykinesia (slowed movements), tremor and rigidity.
I hope this is helpful to you
Regards,
Dr. Robinson

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