Which of the following drugs displaces plasma protein-bound phenytoin as well as decreases its metabolism

Correct Answer: B

Rationale: In this question, the correct answer is B) Sodium valproate. Sodium valproate displaces plasma protein-bound phenytoin and decreases its metabolism through inhibition of hepatic metabolizing enzymes. This interaction can lead to an increase in free phenytoin levels, potentially causing toxicity. Carbamazepine (A) is an enzyme inducer that can increase the metabolism of phenytoin, leading to decreased phenytoin levels. Cimetidine (C) inhibits hepatic microsomal enzymes, but it does not displace phenytoin from plasma proteins. Chloramphenicol (D) inhibits hepatic drug metabolism but does not displace phenytoin from plasma proteins. In an educational context, understanding drug interactions is crucial for healthcare professionals to ensure safe and effective pharmacotherapy. Knowledge of how drugs interact can help in predicting and preventing adverse effects and optimizing treatment outcomes for patients. It is essential to be aware of specific drug interactions, like the one between sodium valproate and phenytoin, to make informed clinical decisions and provide quality patient care.

Correct Answer: C

Rationale: In the treatment of parkinsonism, bromocriptine is used as a supplement to levodopa because when used alone, its effective doses produce intolerable side effects. This is the correct answer (Option C) because bromocriptine, a dopamine receptor agonist, can lead to adverse effects such as nausea, vomiting, dizziness, and hallucinations when used at doses required for efficacy in treating Parkinson's disease. Option A (low efficacy) is incorrect because bromocriptine does have efficacy in targeting dopamine receptors, but the issue lies in the side effect profile when used at effective doses. Option B (first dose hypotension) is incorrect as this side effect is typically associated with other medications like dopamine agonists used in Parkinson's disease. Option D (therapeutic effect takes a long time to develop) is incorrect as bromocriptine can have a relatively quick onset of action due to its direct action on dopamine receptors. Educationally, it is important for healthcare providers to understand the rationale behind using bromocriptine as an adjunct to levodopa in the treatment of parkinsonism to optimize patient outcomes and minimize side effects. Understanding the pharmacological properties of CNS drugs like bromocriptine can help healthcare professionals make informed decisions in clinical practice.

Correct Answer: C

Rationale: In the context of CNS Drugs Pharmacology, the correct answer is C) Haloperidol. Haloperidol is a high-potency antipsychotic drug that is known for its minimal sedative and autonomic effects. It is also associated with no propensity to cause weight gain, making it a favorable choice for some patients. A) Chlorpromazine is a low-potency antipsychotic that is known to have significant sedative effects, autonomic effects, and a higher likelihood of causing weight gain compared to Haloperidol. B) Triflupromazine is another low-potency antipsychotic drug that has sedative effects and a propensity for weight gain, unlike Haloperidol. D) Reserpine is not an antipsychotic drug but rather a medication used for the treatment of hypertension. It works by depleting stores of catecholamines, leading to sedative effects and other adverse effects, which are not characteristic of Haloperidol. Educationally, understanding the differences between antipsychotic drugs in terms of potency, side effect profiles, and clinical use is crucial for healthcare professionals in selecting the most appropriate treatment for patients with psychiatric disorders. Knowing the specific characteristics of each drug can help in optimizing therapy and improving patient outcomes.

Correct Answer: D

Rationale: In the context of CNS drugs pharmacology, it is crucial to understand the potential side effects of different medications to ensure safe and effective patient care. In this question, the correct answer is D) Trazodone. Trazodone is an antidepressant medication that belongs to the class of serotonin antagonist and reuptake inhibitors (SARIs). One of the known side effects of trazodone is priapism, which is a prolonged and painful erection of the penis. This occurs due to the drug's effect on alpha-adrenergic receptors, leading to impaired blood flow regulation in the penis. Now, let's analyze why the other options are incorrect: A) Doxepin and B) Trimipramine are tricyclic antidepressants (TCAs) that are not commonly associated with priapism as a side effect. These medications work through different mechanisms compared to trazodone. C) Mianserin is a tetracyclic antidepressant that also does not typically cause priapism as a side effect. Its pharmacological profile differs from trazodone, leading to a lower likelihood of this specific side effect. Educationally, understanding the side effect profiles of CNS drugs is essential for healthcare professionals to anticipate, recognize, and manage potential adverse reactions in patients. This knowledge helps in making informed decisions regarding medication selection, monitoring, and patient education to ensure optimal therapeutic outcomes while minimizing risks.

Correct Answer: C

Rationale: In this pharmacology question, the correct answer is C) Enalapril. Enalapril is an angiotensin-converting enzyme (ACE) inhibitor commonly used to manage hypertension and heart failure. While it does not have a direct therapeutic effect on senile dementia, it indirectly benefits cognitive function through its ability to improve cerebral blood flow and vascular health. Now, let's analyze why the other options are incorrect: A) Digoxin: Digoxin is a cardiac glycoside used to treat heart conditions like heart failure and atrial fibrillation. It does not have a direct role in the treatment of senile dementia. B) Furosemide: Furosemide is a loop diuretic primarily used to manage conditions such as edema and hypertension by promoting diuresis. It does not have any specific therapeutic effect on senile dementia. D) Amrinone: Amrinone is a phosphodiesterase inhibitor that has inotropic effects and is used in the treatment of acute heart failure. It does not have a recognized therapeutic benefit in senile dementia. Educational Context: Understanding the pharmacological properties of drugs is crucial for healthcare professionals to make informed decisions when prescribing medications. In this case, linking the pharmacological effects of drugs to their potential therapeutic benefits in different conditions is essential. It also highlights the interconnectedness of various body systems and how drugs can have effects beyond their primary indications. This question underscores the importance of comprehensive drug knowledge in clinical practice.