Which instruction is important for the nurse to include when teaching a patient about imatinib therapy?

Correct Answer: A

Rationale: Grapefruit juice can inhibit the metabolism of imatinib, leading to increased drug levels and a higher risk of side effects. Patients should be advised to avoid grapefruit juice while on imatinib therapy. Headaches are not typically an emergency unless severe or accompanied by other symptoms. Imatinib is a long-term treatment, not one that stops working after 2 months. Taking the drug on an empty stomach is not required; it can be taken with food to reduce gastrointestinal side effects.

Correct Answer: B

Rationale: Dizziness is a common side effect of many blood pressure medications, particularly during the initial days of therapy. This side effect increases the patient's risk of falls or other injuries, especially in elderly patients or those with mobility issues. The nursing diagnosis 'Risk for injury' is the most appropriate because it directly addresses the potential harm caused by dizziness. While 'Activity intolerance' and 'Self-care deficit' may be relevant in some cases, they do not specifically address the immediate risk posed by dizziness. 'Disturbed body image' is unrelated to this scenario. Therefore, 'Risk for injury' is the best diagnosis to guide nursing interventions, such as monitoring the patient and educating them on safety measures.

Correct Answer: C

Rationale: Levothyroxine (Synthroid) is a synthetic thyroid hormone used to treat hypothyroidism. Overdose or excessive dosing can lead to symptoms of hyperthyroidism, including tachycardia (rapid heart rate), palpitations, and anxiety. Hypotension and bradycardia are not typical adverse effects of levothyroxine. Constipation is more commonly associated with hypothyroidism, not its treatment. Therefore, tachycardia is the correct answer as it reflects the potential for overstimulation of the cardiovascular system due to excessive thyroid hormone levels.

Correct Answer: B

Rationale: Steady-state concentration is reached after 4-5 half-lives, when drug input equals output. Digoxin's half-life is 40 hours (1.67 days). Four half-lives is 4 × 40 = 160 hours (6.67 days), and five is 200 hours (8.33 days). Over 90% steady state occurs around 4 half-lives, roughly 6-7 days. Two days (48 hours) is only ~1.2 half-lives, far too short. Ten days (~6 half-lives) exceeds 90%, but 7 days (~4.2 half-lives) aligns with >90% (e.g., 94% at 4 half-lives). Fourteen or 18 days overshoot unnecessarily. Seven days balances precision and practicality, guiding digoxin dosing timelines in heart failure or arrhythmias.

Correct Answer: D

Rationale: Volume of distribution (Vd) is a pharmacokinetic parameter reflecting the extent a drug distributes into body tissues relative to plasma. It's not always a real volume, as it can exceed total body water (e.g., for lipophilic drugs), making that statement false. The second option is nonsensical due to unclear phrasing, but likely intends a ratio that's incorrectly stated. The third option reverses the correct formula and is also gibberish. The accurate definition is the amount of drug in the body divided by its concentration in plasma (Vd = Dose / Cp), which quantifies how widely a drug disperses. This isn't about area under the curve (AUC) or dose, as some might confuse with clearance. Understanding Vd is crucial for dosing adjustments, especially for drugs with high tissue affinity, where a large Vd indicates extensive distribution beyond plasma, impacting therapeutic strategies.