A patient with Parkinson's syndrome receives continuous levodopa to increase the level of?

NORCET 2 -2021 (Shift-2)

Pharmacology

Easy

Appeared in: NORCET 2 -2021 (Shift-2)

Explanation

Parkinson's disease is primarily caused by the degeneration of dopamine-producing neurons in the substantia nigra region of the brain.
This leads to a deficiency of the neurotransmitter dopamine, which is crucial for controlling movement.
Levodopa is the metabolic precursor to dopamine. It is administered because dopamine itself cannot cross the blood-brain barrier.
Once in the brain, levodopa is converted into dopamine, which helps to alleviate the motor symptoms of Parkinson's disease by replenishing the deficient neurotransmitter.

Option B: Levodopa does not increase acetylcholine levels. In Parkinson's, there is a relative excess of acetylcholine compared to dopamine, which contributes to symptoms like tremors. Therefore, increasing acetylcholine would worsen the condition.
Option C: GABA (gamma-aminobutyric acid) is the primary inhibitory neurotransmitter in the central nervous system. While its pathways are involved in the basal ganglia circuitry affected by Parkinson's, Levodopa's primary action is not to increase GABA.
Option D: Serotonin is involved in regulating mood, sleep, and appetite. While non-motor symptoms in Parkinson's can be related to serotonin pathway dysfunction, Levodopa does not primarily increase serotonin levels to treat motor symptoms.

Visual 1: Diagram - A diagram illustrating the synapse in the substantia nigra, showing the loss of dopamine neurons in Parkinson's disease and the mechanism of Levodopa crossing the blood-brain barrier and converting to dopamine.
Visual 2: Flowchart - A flowchart depicting the pathophysiology of Parkinson's, starting from dopamine neuron degeneration to the resulting imbalance between dopamine and acetylcholine, and how Levodopa therapy restores this balance.

Clinical Relevance

Nursing practice connection: Use the key finding related to Mechanism of action of Levodopa in Parkinson's disease to guide bedside assessment, documentation, and the next nursing action.
Nurses must educate patients that the goal of Levodopa therapy is to manage symptoms, not to cure the disease. The effectiveness can diminish over time.
Monitoring for the 'on-off' phenomenon is crucial. This involves periods of good symptom control ('on') alternating with periods of poor control ('off') as the drug's effect wears off.
Patient education should include taking Levodopa on an empty stomach or with a low-protein snack, as dietary amino acids can compete with its absorption and transport to the brain.

How to Approach the Question

First, identify the core concepts in the question: the disease (Parkinson's syndrome) and the drug (levodopa).
Recall the primary pathophysiology of Parkinson's disease, which is a deficiency of a specific neurotransmitter.
Remember that the name 'levodopa' hints at its relationship with 'dopamine'. It is a precursor.
Evaluate the function of the drug given. Levodopa is the most common drug for Parkinson's, and its purpose is to replace the missing neurotransmitter.
Analyze the options. Dopamine is the neurotransmitter deficient in Parkinson's. The other options (Acetylcholine, GABA, Serotonin) are other neurotransmitters with different primary functions.

Concept Tested & Keywords

QvNQK2KvFD-5-v4ty9CU2d