Tick the feature of the sublingual route:

Correct Answer: A

Rationale: The correct answer is A: Pretty fast absorption. Sublingual route involves placing the drug under the tongue for direct absorption into the bloodstream through the highly vascular sublingual mucosa. This bypasses the first-pass metabolism in the liver, leading to faster onset of action compared to oral administration. Choice B is incorrect because sublingual administration avoids exposure to gastric secretion. Choice C is incorrect as sublingual administration bypasses liver metabolism. Choice D is incorrect as the variety of doses does not specifically relate to the sublingual route.

Correct Answer: B

Rationale: The correct answer is B, Bupivacaine. Bupivacaine is a long-acting local anesthetic with intrinsic vasoconstrictive properties, so using additional vasoconstrictors may not significantly prolong its anesthetic effects. Procaine (A), Lidocaine (C), and Mepivacaine (D) do not have intrinsic vasoconstrictive properties, so adding vasoconstrictors can help prolong their anesthetic effects.

Correct Answer: C

Rationale: The correct answer is C - On effector cell membranes of glandular and smooth muscle cells. The M3 receptor subtype is a muscarinic acetylcholine receptor, which is primarily located on the effector cell membranes of glandular and smooth muscle cells. This receptor subtype plays a key role in mediating parasympathetic responses in these cells. A: In the myocardium - This is incorrect as the M2 receptor subtype is predominantly located in the myocardium, not the M3 subtype. B: In sympathetic postganglionic neurons - This is incorrect as muscarinic receptors are not typically found in sympathetic neurons. D: On the motor end plates - This is incorrect as nicotinic acetylcholine receptors, not muscarinic receptors, are located on motor end plates.

Correct Answer: B

Rationale: The correct answer is B: Tubocurarine. Tubocurarine has the potential to cause the greatest release of histamine among the choices. This is because tubocurarine is a non-depolarizing neuromuscular blocking agent that can directly stimulate histamine release from mast cells, leading to histamine-related adverse effects like hypotension and bronchospasm. Succinylcholine (A) mainly activates nicotinic acetylcholine receptors, while Pancuronium (C) and Rocuronium (D) are less likely to cause significant histamine release compared to Tubocurarine.

Correct Answer: B

Rationale: The correct answer is B: It is used to treat bronchospasm. Dobutamine is a beta1-selective synthetic catecholamine used for its positive inotropic effects in conditions like heart failure. Choice A is correct as dobutamine is beta1-selective. Choice C is incorrect as dobutamine can increase atrioventricular conduction. Choice D is incorrect as dobutamine can cause changes in heart rate and systolic pressure. Therefore, the correct answer is B because dobutamine is not used to treat bronchospasm.