ATI RN
Pharmacology Practice Exam ATI Questions
Question 1 of 5
A patient looks up the drug he is taking in a drug guide. The patient asks the nurse why the physician prescribed a medication that has a lethal dose measure. What is the best response by the nurse?
Correct Answer: B
Rationale: Lethal dose (e.g., LD50) from research guides safe dosing by showing toxicity thresholds, reassuring the patient it informs, not dictates, prescription. It's not just research trivia-doctors use it indirectly. Side effect watching doesn't explain it. Deferring to the doctor avoids education. Research value ties to safety, clarifying its relevance.
Question 2 of 5
A client takes calcium three times a day in the form of supplements. The nurse will advise the client to take the drug
Correct Answer: D
Rationale: Calcium absorbs best with food-fat aids uptake, per pharmacokinetics-unlike empty stomach or tea (tannins bind). Zinc competes-separate dosing. Food optimizes, per guidance.
Question 3 of 5
A 29-year-old woman presents to her primary care physician for a regular yearly checkup. She has a history of a seizure disorder and has been taking an antiseizure medication for 8 years. She is also taking an oral contraceptive. She is in good health but complains that her gums seem to be overgrowing her teeth. Which of the following medications is likely responsible for her chief complaint?
Correct Answer: C
Rationale: Gingival hyperplasia is a side effect of Phenytoin , an antiseizure drug. Estrogen and Progesterone in contraceptives don't cause this. Lamotrigine and Valproic acid (E) lack this effect. Phenytoin's long-term use induces gum overgrowth, fitting her 8-year history.
Question 4 of 5
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.
Question 5 of 5
Which one of the following is characteristic of both phenytoin and carbamazepine?
Correct Answer: D
Rationale: Phenytoin and carbamazepine are antiepileptic drugs with a shared mechanism: they stabilize neuronal membranes by preventing sodium influx through fast sodium channels, reducing excitability and controlling seizures, particularly in partial and tonic-clonic types. Both induce hepatic cytochrome P450 enzymes, accelerating metabolism of other drugs, not inhibiting it. Phenytoin exhibits zero-order elimination at high doses due to enzyme saturation, while carbamazepine follows first-order kinetics, so this isn't a shared trait. They reduce the efficacy of oral contraceptives by inducing their metabolism, not enhancing them. Safety in pregnancy is questionable, with both linked to teratogenicity (e.g., fetal hydantoin syndrome). The sodium channel blockade is the fundamental property uniting their therapeutic effects, making it the key characteristic they share, critical to their role in epilepsy management.