A patient newly diagnosed with tuberculosis (TB) has been taking antitubercular drugs for 1 week calls the clinic and is very upset. He says, “My urine is dark orange! What’s wrong with me?” Which response by the nurse is correct?

Correct Answer: D

Rationale: The correct answer is D because dark orange urine is a known side effect of antitubercular drugs, specifically rifampin. The nurse should reassure the patient that this is an expected reaction and educate him on what to expect while on the medication. This response helps alleviate the patient's concerns and promotes adherence to the treatment plan. Choice A is incorrect because stopping the medication abruptly can lead to treatment failure. Choice B is incorrect as dark orange urine is not indicative of worsening TB. Choice C is incorrect because it dismisses the patient's concern and does not provide proper information regarding the side effect.

Correct Answer: B

Rationale: The correct answer is B: Bupivacaine. Bupivacaine has a greater potency of local anesthetic action due to its higher lipid solubility and protein binding, leading to a slower onset and longer duration of action compared to other choices. Lidocaine (A) has a faster onset but shorter duration. Procaine (C) has a lower potency due to its lower lipid solubility. Mepivacaine (D) has a similar potency to lidocaine but with a shorter duration of action.

Correct Answer: A

Rationale: Bethanechol is the correct answer as it is mainly muscarinic in action. Bethanechol is a selective muscarinic receptor agonist with minimal nicotinic receptor activity. It is used to stimulate the bladder and gastrointestinal smooth muscle. Carbachol, while also a direct-acting cholinomimetic, has both muscarinic and nicotinic actions. Acetylcholine, the natural neurotransmitter, acts on both muscarinic and nicotinic receptors. "None of the above" is incorrect as Bethanechol is mainly muscarinic in action.

Correct Answer: B

Rationale: The correct answer is B: Pralidoxime. Pralidoxime is an antidote used to regenerate cholinesterase inhibited by organophosphate poisoning, which affects skeletal muscle neuromuscular junctions. It works by reactivating the cholinesterase enzyme, restoring its function. Succinylcholine (A) is a muscle relaxant, not an agent for regenerating cholinesterase. Pirenzepine (C) is a muscarinic receptor antagonist used for gastric ulcers. Propiverine (D) is a bladder antimuscarinic. So, the most effective agent for regenerating cholinesterase at the neuromuscular junction is Pralidoxime.

Correct Answer: D

Rationale: The correct answer is D: Beta 2 receptor. Bronchial smooth muscle relaxation is mainly mediated by Beta 2 adrenergic receptors when activated by agonists like salbutamol. These receptors stimulate adenylate cyclase leading to increased cAMP levels, which in turn promotes muscle relaxation. Alpha 1 receptors (Choice A) and Alpha 2 receptors (Choice B) are associated with vasoconstriction and decreased sympathetic outflow, respectively, not bronchial smooth muscle relaxation. Beta 1 receptors (Choice C) are primarily found in the heart and play a role in cardiac function, not bronchial smooth muscle relaxation.