LEHNE PHARM CENTRAL NERVOUS SYSTEM
PHARMACOLOGY PRACTICE QUESTION AND
ANSWERS 100% DETAILED RATIONALES EXAM
LATEST UPDATE 2026-2027.
1. Parkinson disease is primarily associated with degeneration of neurons in
the:
A. Cerebral cortex
B. Hippocampus
C. Substantia nigra
D. Thalamus
Rationale: Parkinson disease results from progressive loss of dopamine-producing
neurons in the substantia nigra pars compacta.
2. The primary neurotransmitter deficiency in Parkinson disease is:
A. Acetylcholine
B. Serotonin
C. Dopamine
D. GABA
Rationale: Motor symptoms develop because of dopamine depletion in the basal
ganglia.
3. Which of the following is a cardinal symptom of Parkinson disease?
A. Aphasia
B. Resting tremor
C. Blindness
D. Seizures
Rationale: Resting tremor is one of the classic manifestations along with rigidity
and bradykinesia.
, 4. Bradykinesia refers to:
A. Muscle weakness
B. Tremor during movement
C. Slowness of movement
D. Loss of sensation
Rationale: Bradykinesia is characterized by difficulty initiating and performing
voluntary movements.
5. The most effective drug for symptomatic management of Parkinson disease
is:
A. Benztropine
B. Selegiline
C. Levodopa
D. Amantadine
Rationale: Levodopa remains the gold standard for improving motor symptoms.
6. Levodopa acts by:
A. Blocking dopamine receptors
B. Serving as a dopamine precursor
C. Inhibiting acetylcholine synthesis
D. Activating serotonin receptors
Rationale: Levodopa crosses the blood-brain barrier and is converted into
dopamine.
7. Why is dopamine itself not administered to treat Parkinson disease?
A. It is rapidly excreted
B. It causes severe sedation
C. It does not cross the blood-brain barrier
D. It lacks receptor activity
Rationale: Dopamine cannot effectively enter the CNS, whereas levodopa can.
8. Carbidopa is combined with levodopa because it:
A. Enhances dopamine breakdown
, B. Increases renal clearance
C. Inhibits peripheral decarboxylation of levodopa
D. Stimulates dopamine receptors
Rationale: Carbidopa prevents peripheral conversion of levodopa, increasing CNS
availability.
9. Carbidopa does not significantly enter the:
A. Liver
B. Kidney
C. Brain
D. Plasma
Rationale: Carbidopa acts primarily in peripheral tissues and has minimal CNS
penetration.
10.The combination of levodopa and carbidopa reduces:
A. Insomnia
B. Weight gain
C. Peripheral adverse effects
D. Dependence
Rationale: Reduced peripheral dopamine formation decreases nausea and
cardiovascular effects.
11.A common early adverse effect of levodopa is:
A. Agranulocytosis
B. Hyperglycemia
C. Nausea and vomiting
D. Cataracts
Rationale: Peripheral dopamine stimulation frequently causes gastrointestinal
discomfort.
12.Long-term levodopa therapy commonly results in:
A. Hepatic failure
B. Dyskinesias
PHARMACOLOGY PRACTICE QUESTION AND
ANSWERS 100% DETAILED RATIONALES EXAM
LATEST UPDATE 2026-2027.
1. Parkinson disease is primarily associated with degeneration of neurons in
the:
A. Cerebral cortex
B. Hippocampus
C. Substantia nigra
D. Thalamus
Rationale: Parkinson disease results from progressive loss of dopamine-producing
neurons in the substantia nigra pars compacta.
2. The primary neurotransmitter deficiency in Parkinson disease is:
A. Acetylcholine
B. Serotonin
C. Dopamine
D. GABA
Rationale: Motor symptoms develop because of dopamine depletion in the basal
ganglia.
3. Which of the following is a cardinal symptom of Parkinson disease?
A. Aphasia
B. Resting tremor
C. Blindness
D. Seizures
Rationale: Resting tremor is one of the classic manifestations along with rigidity
and bradykinesia.
, 4. Bradykinesia refers to:
A. Muscle weakness
B. Tremor during movement
C. Slowness of movement
D. Loss of sensation
Rationale: Bradykinesia is characterized by difficulty initiating and performing
voluntary movements.
5. The most effective drug for symptomatic management of Parkinson disease
is:
A. Benztropine
B. Selegiline
C. Levodopa
D. Amantadine
Rationale: Levodopa remains the gold standard for improving motor symptoms.
6. Levodopa acts by:
A. Blocking dopamine receptors
B. Serving as a dopamine precursor
C. Inhibiting acetylcholine synthesis
D. Activating serotonin receptors
Rationale: Levodopa crosses the blood-brain barrier and is converted into
dopamine.
7. Why is dopamine itself not administered to treat Parkinson disease?
A. It is rapidly excreted
B. It causes severe sedation
C. It does not cross the blood-brain barrier
D. It lacks receptor activity
Rationale: Dopamine cannot effectively enter the CNS, whereas levodopa can.
8. Carbidopa is combined with levodopa because it:
A. Enhances dopamine breakdown
, B. Increases renal clearance
C. Inhibits peripheral decarboxylation of levodopa
D. Stimulates dopamine receptors
Rationale: Carbidopa prevents peripheral conversion of levodopa, increasing CNS
availability.
9. Carbidopa does not significantly enter the:
A. Liver
B. Kidney
C. Brain
D. Plasma
Rationale: Carbidopa acts primarily in peripheral tissues and has minimal CNS
penetration.
10.The combination of levodopa and carbidopa reduces:
A. Insomnia
B. Weight gain
C. Peripheral adverse effects
D. Dependence
Rationale: Reduced peripheral dopamine formation decreases nausea and
cardiovascular effects.
11.A common early adverse effect of levodopa is:
A. Agranulocytosis
B. Hyperglycemia
C. Nausea and vomiting
D. Cataracts
Rationale: Peripheral dopamine stimulation frequently causes gastrointestinal
discomfort.
12.Long-term levodopa therapy commonly results in:
A. Hepatic failure
B. Dyskinesias
