Correct statements concerning aspirin include all of the following EXCEPT:

Correct Answer: B

Rationale: The correct answer is B because aspirin does have an anti-inflammatory effect by inhibiting COX enzymes, reducing prostaglandin synthesis. A is correct as aspirin inhibits mainly peripheral COX-1. C is correct as aspirin inhibits platelet aggregation by blocking thromboxane synthesis. D is incorrect as aspirin does not stimulate respiration but can cause respiratory alkalosis at toxic doses due to metabolic acidosis.

Correct Answer: A

Rationale: The correct answer is A: Caffeine. Caffeine is a methylxanthine derivative known for its psychostimulant effects on the central nervous system. Methylxanthines are a class of compounds that include caffeine, theophylline, and theobromine, all of which act as stimulants. Sydnocarb (B) is a psychostimulant but not a methylxanthine derivative. Amphetamine (C) is a different class of psychostimulant compounds, and Meridil (D) is not a psychostimulant. Therefore, caffeine is the correct choice as the methylxanthine derivative with psychostimulant properties.

Correct Answer: D

Rationale: Addiction involves both psychological and physiological components. Psychological dependence refers to the emotional reliance on a substance or behavior, while physiological dependence involves changes in the body that lead to withdrawal symptoms. Tolerance is a phenomenon where more of a substance is needed to achieve the same effects. Therefore, all of the above options are associated with addiction, making choice D the correct answer.

Correct Answer: B

Rationale: The correct answer is B: Flumazenil. Flumazenil is a specific benzodiazepine receptor antagonist that competitively inhibits the effects of benzodiazepines like midazolam, accelerating recovery from sedative actions. Naloxone (A) is used to reverse opioid effects, not benzodiazepines. Ketamine (C) is a dissociative anesthetic and not used to reverse benzodiazepine sedation. Fomepizole (D) is used in methanol or ethylene glycol toxicity, not for benzodiazepine reversal. Flumazenil is the specific antidote for benzodiazepine overdose.

Correct Answer: A

Rationale: Step-by-step rationale for choice A: 1. Metoclopramide is known to block dopamine receptors, making it a dopamine antagonist. 2. This action helps in treating nausea, vomiting, and gastrointestinal issues by enhancing motility. 3. Therefore, the statement that Metoclopramide is a potent dopamine antagonist is TRUE. Summary of other choices: B: FALSE - Incorrect, as Metoclopramide is indeed a dopamine antagonist. C: All - Incorrect, as not all the choices are correct. D: None of the above - Incorrect, as the correct answer is A.