A patient with coronary artery disease asks the nurse about the "good cholesterol" laboratory values. The nurse knows that "good cholesterol" refers to which lipids?

Choice A reason: Blurred vision and headaches are not common side effects of niacin. Niacin lowers lipids by inhibiting hepatic VLDL production but primarily causes cutaneous effects like flushing due to prostaglandin release. Neurological symptoms are more associated with other drugs, not niacin’s lipid-lowering mechanism.

Choice B reason: Myalgia and fatigue are not typical niacin side effects. These are more associated with statins, which affect muscle tissue. Niacin’s primary adverse effects involve skin (flushing, pruritus) and gastrointestinal upset, driven by its vasodilatory and metabolic effects, not musculoskeletal symptoms.

Choice C reason: Tinnitus and urine with a burnt odor are not recognized niacin side effects. Niacin causes prostaglandin-mediated flushing and potential hepatotoxicity but does not affect auditory function or urine odor. These symptoms are unrelated to niacin’s mechanism of reducing lipid synthesis.

Choice D reason: Pruritus and cutaneous flushing are common niacin side effects. Niacin triggers prostaglandin release, causing vasodilation, leading to flushing and itching. These effects are dose-dependent and often transient, manageable with aspirin pretreatment or gradual dose escalation, making this the correct adverse effect to monitor.

Choice A reason: Quinolones, like ciprofloxacin, inhibit bacterial DNA gyrase and have no structural similarity to penicillin. They are safe in penicillin-allergic patients, as there is no cross-reactivity. Their side effects, like tendonitis, are unrelated to penicillin’s beta-lactam ring, making this class safe.

Choice B reason: Sulfonamides, like trimethoprim-sulfamethoxazole, inhibit bacterial folate synthesis and are not structurally related to penicillin. They do not cause cross-reactivity in penicillin-allergic patients. Their hypersensitivity reactions are distinct, making them a safe alternative for patients with penicillin allergies.

Choice C reason: Cephalosporins share a beta-lactam ring with penicillins, leading to a 5-10% cross-reactivity risk in penicillin-allergic patients. Allergic reactions, like anaphylaxis, may occur, so the nurse should question cephalosporin orders, especially for first-generation agents, to ensure patient safety.

Choice D reason: Tetracyclines, like doxycycline, inhibit protein synthesis and have no structural similarity to penicillin’s beta-lactam ring. They are safe in penicillin-allergic patients, with no cross-reactivity risk. Their side effects, like photosensitivity, are unrelated to penicillin allergies, making this class safe.