ATI RN
Chapter 2 pharmacologic principles Questions
Question 1 of 5
Which of the following functional groups is most susceptible to hydrolysis?
Correct Answer: B
Rationale: R-COOR (B), an ester, is most susceptible to hydrolysis, cleaved by water into an acid and alcohol (e.g., aspirin to salicylic acid), common in drug degradation. R-CO-R (A, ketone) and R-O-R (C, ether) resist hydrolysis. R-NH-CH₃ (D, amine) and R-COOH (original E, acid) are stable. Esters' labile carbonyl-oxygen bond, catalyzed by pH or enzymes, drives this susceptibility, necessitating stable formulations (e.g., dry storage), a critical stability factor in pharmaceuticals.
Question 2 of 5
Urticaria that appears rapidly after the ingestion of food usually indicates which type of hypersensitivity reaction?
Correct Answer: A
Rationale: Type I hypersensitivity (A) causes rapid urticaria post-food ingestion (e.g., peanut allergy), an IgE-mediated reaction releasing histamine, leading to hives within minutes. Type II (B) is cytotoxic (e.g., transfusion reactions). Type III (C) involves immune complexes (e.g., serum sickness). Type IV (D) is delayed (e.g., contact dermatitis). No original E. This immediate response, treatable with epinephrine, underscores Type I's mast cell degranulation, critical in allergy management and pharmacology.
Question 3 of 5
Flurazepam has pKa of 8.2. What percentage of flurazepam will be ionized at a urine pH of 5.2 ?
Correct Answer: B
Rationale: Flurazepam (pKa 8.2), a weak base, is 1% ionized at urine pH 5.2 (B). Henderson-Hasselbalch: pH = pKa + log([B]/[BHâº]); 5.2 = 8.2 + log([B]/[BHâº]), log([B]/[BHâº]) = -3, [B]/[BHâº] = 0.001, so BH⺠(ionized) is 99.9/100.9 ≈ 99%, un-ionized ~1%. Options A (0.1%), C (50%), and D (99%) miscalculate. Option E (original, 99.9%) inverts. This low ionization favors reabsorption, slowing excretion, relevant in benzodiazepine pharmacokinetics and overdose management.
Question 4 of 5
Which of the following radionuclides is generator produced?
Correct Answer: A
Rationale: â¹â¹áµTc (A) is generator-produced, from â¹â¹Mo decay (tâ‚/â‚‚ 66h) in a molybdenum-technetium generator, yielding gamma-emitting Tc-99m (tâ‚/â‚‚ 6h) for imaging (e.g., thyroid scans). ²â°Â¹Tl (B), â¶â·Ga (C), ¹³³Xe (D), and ¹²³I (original E) are
Question 5 of 5
A hospitalized patient with systemic candidiasis is receiving intravenous antifungal medications. He also has hepatic and renal insufficiency. Which of the following drug administration schemes would allow for the most steady state amount of drug in the body over a 2-week hospitalization period where medication administration will be necessary?
Correct Answer: A
Rationale: Continuous IV infusion (A) provides the most steady-state drug levels over 2 weeks in a patient with systemic candidiasis and hepatic/renal insufficiency. It delivers a constant rate, compensating for impaired clearance (e.g., antifungals like amphotericin), avoiding peaks/troughs of intermittent dosing (B, C, D, E original). Weekly (B) or twice-weekly (E) injections risk subtherapeutic gaps; daily (C) or twice-daily (D) cause fluctuations. Steady-state maintenance is critical in severe infections with compromised metabolism/excretion, ensuring consistent therapeutic levels, reducing toxicity, and optimizing outcomes in critical care.