ATI RN
Basic pharmacology principles Questions
Question 1 of 5
Glucose is a carbohydrate that cannot be hydrolyzed into a simpler substance. It is best described as
Correct Answer: B
Rationale: Glucose is best described as a monosaccharide (B), a single sugar unit (C₆Hâ‚â‚‚O₆) not hydrolyzable into simpler carbohydrates, serving as an energy source (e.g., dextrose IV). A sugar (A) is broader. Disaccharides (C, e.g., sucrose) and polysaccharides (D, e.g., starch) hydrolyze. Oligosaccharides (original E) are 3-10 units. Glucose's simplicity drives its rapid absorption, critical in hypoglycemia treatment, distinguishing it in carbohydrate chemistry and pharmacokinetics.
Question 2 of 5
CD4+T cells specifically recognize antigens in which form?
Correct Answer: C
Rationale: CD4+ T cells recognize antigens bound to MHC class II molecules on antigen-presenting cells (APCs) (C), like macrophages, triggering helper T-cell responses (e.g., cytokine release). MHC class I (A) is for CD8+ cells. Free antigens (B) don't activate T cells directly. No option D or original E. This MHC II restriction drives adaptive immunity, critical in vaccine design and immunosuppressive drugs (e.g., cyclosporine), shaping immune pharmacology.
Question 3 of 5
The excretion of a weakly acidic drug generally is more rapid in alkaline urine than in acidic urine. This process occurs because
Correct Answer: A
Rationale: A weak acid is excreted faster in alkaline urine because it exists primarily in its ionized form (A), less reabsorbed by renal tubules (e.g., aspirin at pH 8 > pKa 3.5), per Henderson-Hasselbalch. Option B is false; ionized is hydrophilic, not lipophilic. Option C is incorrect; pH effect is drug-specific. No option D or original E. This ion trapping accelerates clearance (e.g., in overdose), a key pharmacokinetic strategy, manipulating urine pH for therapeutic benefit.
Question 4 of 5
A 28-year-old man with seborrheic dermatitis is prescribed a topical corticosteroid crème by his dermatologist in hopes of alleviating the chronic rash and erythema on the cheeks. Which of the following steps is most critical to achieve a therapeutic drug concentration in plasma?
Correct Answer: A
Rationale: Absorption (A) is most critical to achieve a therapeutic plasma concentration for a topical corticosteroid. Applied to the skin, the drug must penetrate the stratum corneum to reach dermal blood vessels for systemic uptake (e.g., hydrocortisone for inflammation). Distribution (B) occurs post-absorption, spreading drug to tissues. Elimination (C) removes it, reducing levels. Glycosylation (D) and metabolism (original E) are irrelevant to initial plasma entry. Poor absorption (e.g., due to thick skin or low lipid solubility) limits systemic levels, critical for efficacy in seborrheic dermatitis if systemic effects are needed, though topical drugs primarily act locally, with plasma levels as a secondary outcome.
Question 5 of 5
A hospitalized patient with systemic infection is receiving intravenous antibiotics. He also has hepatic and renal insufficiency. After receiving medications for 5 days, he is found by nursing staff to be jaundiced. Drug toxicology profile is obtained and indicated drug levels of 10 times the acceptable value. Which of the following drug administration schemes is most likely to explain this situation?
Correct Answer: A
Rationale: Continuous IV infusion (A) most likely explains the toxic drug levels (10× normal) and jaundice in this patient with hepatic and renal insufficiency. Constant delivery (e.g., vancomycin) overwhelms impaired clearance, causing accumulation over 5 days. Weekly (B) or twice-weekly (original E) injections allow recovery periods, less likely to build up. Daily (C) or twice-daily (D) bolus dosing risks peaks but less sustained excess than infusion. In hepatic/renal failure, reduced metabolism/excretion (e.g., bilirubin rise causing jaundice) amplifies toxicity, highlighting infusion's risk in such patients, requiring dose adjustment.