Which of the following agents is a general tone-increasing drug of plant origin?

Correct Answer: B

Rationale: The correct answer is B: Eleuterococci's extract. This plant origin drug is known for its adaptogenic properties, which help increase overall tone and resilience in the body. Eleuterococci, also known as Siberian ginseng, is used to combat stress and boost energy levels. Meridil (A) is a synthetic drug with unknown effects on tone. Pantocrin (C) is a hormone derived from animal glands, not a plant origin drug. Caffeine (D) is a stimulant that may increase alertness but does not have the same generalized tone-increasing properties as Eleuterococci's extract.

Correct Answer: A

Rationale: The correct answer is A: Enflurane. Enflurane can lower the seizure threshold, making it risky for patients with a history of seizure disorders. Nitrous oxide (B), Sevoflurane (C), and Desflurane (D) are considered safer options and do not have as significant an effect on seizure threshold. Therefore, Enflurane should be avoided in patients with a history of seizure disorders to prevent potential complications.

Correct Answer: A

Rationale: Step-by-step rationale: - Misoprostol is a synthetic prostaglandin E1 analog used to prevent gastric ulcers, not an antacid. - Maalox, Mylanta, and Almagel are all antacids used to neutralize stomach acid. - Misoprostol increases gastric mucus production, inhibits acid secretion, and promotes healing of the stomach lining. - Therefore, the correct answer is A (Misoprostol) as it is not an antacid but rather a medication used to prevent ulcers.

Correct Answer: B

Rationale: The correct answer is B: Streptokinase. Streptokinase is a fibrinolytic drug that helps break down blood clots by activating plasminogen. This process helps improve blood flow in conditions like myocardial infarction or stroke. Ticlopidine (A) is an antiplatelet drug, Aspirin (C) is also an antiplatelet agent, and Warfarin (D) is an anticoagulant. These drugs work differently from fibrinolytics and do not directly dissolve blood clots like Streptokinase does.

Correct Answer: A

Rationale: The correct answer is A (Nifedipine) because it is a calcium channel blocker that primarily acts on vascular smooth muscle, leading to vasodilation without significant effects on heart rate (chronotropy) or conduction velocity (dromotropy). Diltiazem and Verapamil, choices B and C, are also calcium channel blockers but have more pronounced negative chronotropic and dromotropic effects due to their additional actions on the heart. Choice D is incorrect because Nifedipine specifically has minimal direct effects on chronotropy and dromotropy compared to Diltiazem and Verapamil.