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, 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. Vitamin B6 speeds the conversion of levodopa to dopamine before it
can cross the bloodbrain 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)
d. Vitamin B6