A patient is to receive iron dextran injections. Which technique is appropriate when the nurse is administering this medication?

Correct Answer: C

Rationale: The correct answer is C: Intramuscular injection using the Z-track method. This method helps prevent leakage of the medication into surrounding tissues and minimizes irritation. Step-by-step rationale: 1. Clean the injection site. 2. Pull the skin laterally to create a zig-zag path. 3. Administer the injection deep into the muscle. 4. Hold the needle in place for a few seconds before removing. Summary: A is incorrect because iron dextran is not typically administered intravenously. B is incorrect as intramuscular injections without the Z-track method can lead to leakage and irritation. D is incorrect as iron dextran injections are not given subcutaneously.

Correct Answer: C

Rationale: The correct answer is C: The ability to diffuse to the site of action. Ionizable groups in a molecule can influence its ability to cross cell membranes and reach the target site. Potency and toxicity (choice A) are determined by the molecule's interaction with the target, not just ionizable groups. Duration of action (choice B) can be affected by various factors, not solely ionizable groups. Choice D is incorrect because ionizable groups do not directly impact potency, toxicity, and duration of action simultaneously.

Correct Answer: A

Rationale: Step 1: Acetylcholine is a direct-acting cholinomimetic that quickly hydrolyzes by acetylcholinesterase, leading to a short duration of action. Step 2: Methacholine, Carbachol, and Bethanechol are also direct-acting cholinomimetics but are more resistant to enzymatic degradation, resulting in longer durations of action. Summary: Acetylcholine has the shortest duration of action due to rapid enzymatic degradation compared to the other choices. Methacholine, Carbachol, and Bethanechol have longer durations of action as they are more resistant to enzymatic degradation.

Correct Answer: D

Rationale: Step-by-step rationale: 1. Atropine is an antimuscarinic drug that blocks muscarinic acetylcholine receptors. 2. In mushroom poisoning, toxins can lead to excessive stimulation of muscarinic receptors. 3. Atropine counteracts this effect by blocking the receptors, reducing symptoms like excessive salivation, sweating, and bradycardia. 4. Pralidoxime is used for organophosphate poisoning, not mushroom poisoning. 5. Pilocarpine and homatropine are muscarinic agonists, which would worsen symptoms of mushroom poisoning by further stimulating muscarinic receptors.

Correct Answer: C

Rationale: The correct answer is C: Methoxamine. Beta receptor agonists stimulate beta receptors, leading to various effects like increased heart rate and bronchodilation. Methoxamine is an alpha-1 adrenergic agonist, not a beta receptor agonist. Epinephrine, Isoproterenol, and Dobutamine are all beta receptor agonists, so they are incorrect choices. Epinephrine acts on both alpha and beta receptors, Isoproterenol is a non-selective beta agonist, and Dobutamine primarily targets beta-1 receptors.