Question

Select the CORRECT statement regarding L-Dopa.

1) It is a precursor to tyrosine
2) Dyskinesias occur in 80
3) Carbidopa given with L-dopa worsens GIT side effects
4) Levodopa stops the progression of parkinsonism

Answer 1

The correct statement is that L-Dopa is a precursor to dopamine, which is used to alleviate Parkinson's disease symptoms. It does not halt the progression of Parkinsonism but helps to manage symptoms, and Carbidopa can reduce L-Dopa's peripheral side effects.

Step-by-step explanation:

The correct statement regarding L-Dopa is that it is a precursor to the neurotransmitter dopamine. This is utilized in the treatment of Parkinson's disease to increase dopamine levels in the striatum because L-Dopa has the ability to cross the blood-brain barrier.

Carbidopa is often given in conjunction with L-Dopa to prevent its conversion to dopamine in the peripheral tissues, which does not worsen gastrointestinal (GIT) side effects but rather helps to reduce them by limiting peripheral side effects. It's important to note that L-Dopa does not stop the progression of Parkinsonism but helps to alleviate the symptoms.

Over time, patients may experience dyskinesias, which are involuntary movements, as a side effect of prolonged L-Dopa therapy. However, dyskinesias do not occur in 80% of patients right away but may develop as the disease progresses and treatment duration extends.