MED 143 ANTIPARKINSONISM AGENTS – CHAPTER 24 VERIFIED QUESTIONS AND ANSWERS 2023

MED 143 ANTIPARKINSONISM AGENTS – CHAPTER 24 VERIFIED QUESTIONS AND ANSWERS 2023. Degeneration in neurons that release a neurotransmitter leads to Parkinson's disease. What neurotransmitter is involved? Gamma-aminobutyric acid (GABA) Acetylcholine Dopamine Serotonin s: 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? Benztropine (Cogentin) Diphenhydramine (Benadryl) Trihexyphenidyl (Artane) Procyclidine (Kemadrin) s: 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.) Benign prostatic hypertrophy Narrow-angle glaucoma Myasthenia gravis Dysrhythmias Hepatic dysfunction s: A, B, C Feedback: Anticholinergics are contraindicated in the presence of narrow-angle glaucoma, GI Page 1 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.