A 17-year-old man presents to the emergency department with a persistent cough and nasal congestion. He has been taking various prescription cough and cold medicines but did not know their names. A urine drug screen is positive for amphetamines. When confronted with this information, he vehemently denies amphetamine use. What is the best explanation?

Correct Answer: B

Rationale: Positive amphetamine screen with cough/cold medicine use suggests a false positive from ephedrine . Ephedrine, in decongestants, cross-reacts with amphetamine assays. Codeine and marijuana don't. Lying or sample mix-up (E) are less likely given his denial and context. This common false positive explains the discrepancy.

Correct Answer: B

Rationale: Positive amphetamine screen with cough/cold medicine use suggests a false positive from ephedrine . Ephedrine, in decongestants, cross-reacts with amphetamine assays. Codeine and marijuana don't. Lying or sample mix-up (E) are less likely given his denial and context. This common false positive explains the discrepancy.

Correct Answer: D

Rationale: Spironolactone is a potassium-sparing diuretic that works by promoting potassium retention in the body. Therefore, patients taking spironolactone are at a higher risk of developing hyperkalemia, which is an elevated level of potassium in the blood. Hyperkalemia can lead to serious complications such as cardiac arrhythmias, muscle weakness, and even cardiac arrest. It is important for the nurse to monitor patients on spironolactone for signs and symptoms of hyperkalemia, such as weakness, numbness, tingling, or an irregular heartbeat. Other diuretics like hydrochlorothiazide (A), furosemide (B), and acetazolamide (C) do not typically cause hyperkalemia as they work to decrease potassium levels in the body.

Correct Answer: B

Rationale: High-dose androgens in females are used palliatively for certain breast cancers, especially hormone-sensitive ones, to suppress estrogen-driven tumor growth, easing symptoms in advanced disease. Athletic performance enhancement via androgens, while feasible, isn't clinically indicated and is illegal in regulated contexts. Brain cancer lacks evidence for androgen treatment, as it doesn't target neurological tumors. Sexual reassignment uses testosterone for masculinization, but high doses in clinical settings typically tie to cancer care, not transition. Breast cancer aligns with a recognized therapeutic use, leveraging androgens' anti-estrogenic effects, making it the most valid clinical rationale here.

Correct Answer: B

Rationale: HMG-CoA reductase inhibitors, also known as statins, are a class of antilipemic drugs commonly prescribed to lower cholesterol levels. One side effect associated with statin use is myopathy, which manifests as muscle pain, tenderness, or weakness. In severe cases, myopathy can progress to rhabdomyolysis, a condition characterized by muscle breakdown and release of muscle fiber contents into the blood, potentially leading to kidney damage. It is essential for healthcare providers, such as nurses, to monitor patients on statin therapy for signs and symptoms of myopathy to intervene promptly if necessary. Niacin, fibric acid derivatives, and bile acid sequestrants are not typically associated with myopathy as a common side effect.