An 83-year-old woman with Parkinson's disease is currently being treated with carbidopa/levodopa, but her Parkinson's symptoms are worsening. She has normal liver function and no history of liver disease. The physician adds tolcapone to her regimen on tolcapone. How does tolcapone help in Parkinson's disease?

Correct Answer: B

Rationale: The correct answer is B) Inhibition of COMT. Rationale: Tolcapone is a catechol-O-methyltransferase (COMT) inhibitor. COMT is an enzyme that breaks down levodopa outside the blood-brain barrier, reducing the amount of levodopa available to cross into the brain and be converted to dopamine. By inhibiting COMT, tolcapone increases the availability of levodopa in the brain, enhancing its therapeutic effects in Parkinson's disease. Explanation of other options: A) Increased norepinephrine synthesis: This is not directly related to the mechanism of action of tolcapone in treating Parkinson's disease. Norepinephrine is not the primary neurotransmitter affected in Parkinson's. C) Inhibition of MAO: Monoamine oxidase (MAO) inhibitors are a different class of drugs used in depression and anxiety disorders, not Parkinson's disease. MAO inhibitors do not have a direct role in increasing dopamine levels in the brain. D) Stimulation of acetylcholine release: While acetylcholine does play a role in Parkinson's disease, the primary focus of treatment is on increasing dopamine levels, not acetylcholine release. Stimulation of acetylcholine release would not be the primary mechanism of action for improving Parkinson's symptoms. Educational context: Understanding the mechanisms of action of drugs used in Parkinson's disease is crucial for nurses and healthcare professionals caring for patients with this condition. By grasping how medications like tolcapone work, healthcare providers can make informed decisions about treatment options and monitor for potential side effects or interactions. This knowledge enhances patient care and safety in managing Parkinson's disease effectively.

Correct Answer: C

Rationale: The correct answer is C) Consider discontinuing her medication. The patient is exhibiting symptoms of tardive dyskinesia, a common side effect of long-term use of antipsychotic medications like fluphenazine. Tardive dyskinesia presents as involuntary movements, such as lip puckering, and is irreversible in some cases. Discontinuing the offending medication is crucial to prevent further worsening of symptoms. Option A is incorrect because adding another neuroleptic can exacerbate the symptoms of tardive dyskinesia and is not recommended. Option B, asking about illicit drug use, is not the immediate priority in this scenario, as the patient's symptoms are likely due to her prescribed medication. Option D, increasing the dose of fluphenazine, is contraindicated as it can worsen the symptoms of tardive dyskinesia. This question highlights the importance of monitoring patients on long-term antipsychotic therapy for the development of tardive dyskinesia. Healthcare providers need to be vigilant in recognizing and managing side effects to ensure the overall well-being of their patients. It also emphasizes the need for regular follow-up and assessment of medication side effects in individuals with chronic mental health conditions.

Correct Answer: B

Rationale: In this scenario, the correct answer is B) β-Adrenergic receptors. Chlorpromazine, a low-potency typical antipsychotic, primarily antagonizes dopamine receptors, leading to side effects like dry mouth, constipation, blurred vision, and fatigue. However, it spares β-adrenergic receptors from antagonism. β-Adrenergic receptors are not directly affected by chlorpromazine's mechanism of action. Option A) α-Adrenergic receptors are not the correct answer because chlorpromazine can antagonize these receptors, leading to side effects like orthostatic hypotension and dizziness. Option C) Dopamine receptors are the primary target of chlorpromazine, not spared. Option D) Histamine receptors are antagonized by chlorpromazine, leading to sedation and weight gain in patients. Educationally, understanding the pharmacological actions of antipsychotic medications like chlorpromazine is crucial for nurses and healthcare professionals when managing patients with schizophrenia. Knowing the receptor profiles affected by these drugs helps in anticipating and managing potential side effects effectively.

Correct Answer: D

Rationale: In this scenario, the correct answer is D) Blockade of M receptors. Scopolamine, an anticholinergic medication, prevents motion sickness by blocking muscarinic receptors in the vestibular system, thus reducing the input to the vomiting center in the brain. This action helps alleviate symptoms of motion sickness such as nausea and vomiting. Option A) Blockade of β₁-receptors and B) Blockade of β₂-receptors are related to beta-adrenergic receptors, not involved in the mechanism of action of scopolamine in preventing motion sickness. Option C) Blockade of H₂ receptors is associated with drugs that treat conditions like gastric ulcers and gastroesophageal reflux disease, not motion sickness. Educationally, understanding the pharmacological actions of drugs is crucial for nurses to provide safe and effective care to patients. Knowing how scopolamine works enables nurses to educate patients on its effects and potential side effects, as well as to monitor for adverse reactions while administering the medication. This knowledge enhances patient outcomes and safety during medication administration.

Correct Answer: D

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.