Chapter 24  Antiparkinsonism Agents

Chapter 24  Antiparkinsonism Agents

Complete Chapter Questions And Answers
 

Sample Questions

1. Degeneration in neurons that release a neurotransmitter leads to Parkinson’s disease. What
neurotransmitter is involved?

A) Gamma-aminobutyric acid (GABA)

B) Acetylcholine

C) Dopamine

D) Serotonin

Ans: C

Feedback:

Degeneration of dopamine-releasing neurons in the substantia nigra leads to Parkinson’s disease. When
dopamine is decreased in the area of the corpus striatum, a chemical imbalance allows the cholinergic
or excitatory cells to dominate. This affects the functioning of the basal ganglia and cortical and
cerebellar components of the extrapyramidal motor system. This system provides coordination for
unconscious muscle movements, including those that control position, posture, and movement. The
result of the imbalance produces the signs and symptoms of Parkinson’s disease. The corpus striatum in
the brain is connected to the substantia nigra by a series of neurons that use the inhibitory
neurotransmitter GABA. Higher neurons from the cerebral cortex secrete acetylcholine in the area of
the corpus striatum as an excitatory neurotransmitter to coordinate movements of the body. Serotonin is
not involved in these functions.

2. A 10-year-old boy has been prescribed an antiparkinsonian drug. Which drug would the nurse expect as
the first choice for this child?

A) Benztropine (Cogentin)

B) Diphenhydramine (Benadryl)

C) Trihexyphenidyl (Artane)

D) Procyclidine (Kemadrin)

Ans: B

Feedback:

Parkinson’s disease is rare in children. However, if a child needs an antiparkinsonian drug,

Test Bank – Focus on Nursing Pharmacology (7th Edition by Amy Karch) 389

diphenhydramine is the drug of choice. Benztropine, trihexyphenidyl, and procyclidine are not
recommended for use in children.

3. A patient is newly diagnosed with Parkinson’s disease. An anticholinergic drug is ordered for the
patient. When reviewing the patient’s medical history, the nurse realizes an anticholinergic drug is
contraindicated for this patient because of what secondary diagnosis? (Select all that apply.)

A) Benign prostatic hypertrophy

B) Narrow-angle glaucoma

C) Myasthenia gravis

D) Dysrhythmias

E) Hepatic dysfunction

Ans: A, B, C

Feedback:

Anticholinergics are contraindicated in the presence of narrow-angle glaucoma, GI obstruction,
genitourinary (GU) obstruction, and prostatic hypertrophy, all of which could be exacerbated by the
peripheral anticholinergic effects of these drugs, and in myasthenia gravis, which could be exacerbated
by the blocking of acetylcholine-receptor sites at the neuromuscular synapses. These agents should be
administered cautiously, but they are not contraindicated in therapy for the following conditions:
tachycardia and other dysrhythmias and hypertension or hypotension because the blocking of the
parasympathetic system may cause a dominance of sympathetic stimulatory activity, and in hepatic
dysfunction, which could interfere with the metabolism of the drugs and lead to toxic levels.

4. A patient is newly diagnosed with Parkinson’s disease and levodopa (Dopar) has been prescribed. What
patient teaching information should be considered a high priority for this patient?

A) Avoid vitamin B6 intake.

B) Avoid hot environments.

C) Many adverse effects will subside when the body adjusts to the drug.

D) Allow rest periods.

Ans: A

Feedback:

The priority information would be to avoid vitamin B6 intake, which would include grains and bran.

Test Bank – Focus on Nursing Pharmacology (7th Edition by Amy Karch) 390

Vitamin B6 speeds the conversion of levodopa to dopamine before it can cross the blood​brain barrier.
This leads to Parkinson’s symptoms. The other options are all important and should be discussed with
the patient. However, sweating, headaches, difficulty sleeping, fatigue, weakness, and dizziness are
expected adverse effects, which will eventually subside or decrease.

5. A patient with Parkinsonism has been told that the levodopa prescribed is no longer controlling the
disease. What drug would the nurse question if ordered as adjunctive therapy?

A) Diphenhydramine (Benadryl)

B) Pramipexole (Mirapex)

C) Trihexyphenidyl (Artane)

Vitamin B
D) Vitamin B6

Ans: D

Feedback:

Vitamin B6 would further decrease the therapeutic effects of levodopa and is contraindicated with
levodopa, so the nurse would question this order. Pramipexole, diphenhydramine, and trihexyphenidyl
are all useful adjunctive drugs when Parkinson’s disease is no longer controlled with levodopa therapy
alone.