ATI RN
ATI Intro to Pharmacology Quizlet Questions
Question 1 of 5
Clearance:
Correct Answer: A
Rationale: Clearance (CL = rate of elimination / plasma concentration) is the amount of drug removed per unit time relative to concentration, a true statement defining its calculation. It's constant for first-order kinetics drugs at therapeutic levels, true. Lithium's clearance is moderate, not very high, handled by kidneys, so that's false. Phenytoin's clearance decreases with concentration (zero-order at high doses), not independent, making that false. Clearance isn't inversely proportional to Vd but related via half-life. This definition is essential for dosing regimens, ensuring steady-state maintenance.
Question 2 of 5
At a dose of 10 mg, drug X lowers total cholesterol by 50 mg/dL, while a maximum drop in cholesterol of 65 mg/dL is achieved at 40 mg. At a dose of 5 mg, drug Y lowers cholesterol by 50 mg/dL, while a maximum drop in cholesterol of 55 mg/dL is achieved at 10 mg. What can be concluded about the efficacy and potency of these two drugs?
Correct Answer: D
Rationale: Potency is dose for effect-Drug Y lowers 50 mg/dL at 5 mg, versus X at 10 mg, making Y more potent. Efficacy is max effect-X's 65 mg/dL beats Y's 55 mg/dL, giving X higher efficacy. X isn't more potent-higher dose needed. Y's potency and X's efficacy align with data, per pharmacodynamics.
Question 3 of 5
The physician has prescribed sertraline (Zoloft) for the patient who is anxious and depressed. The patient calls the nurse to report that he has experienced delayed ejaculation since being on this medication. What is the best response by the nurse?
Correct Answer: B
Rationale: Sertraline, an SSRI, often causes sexual side effects like delayed ejaculation-common, per patient data-but depression treatment outweighs this for now. Switching is an option, not immediate. Suicide risk from stopping is possible but not assumed. It rarely resolves alone-management varies. Prioritizing depression balances care, per guidelines.
Question 4 of 5
A 42-year-old woman with a 1-year history of rheumatoid arthritis comes to see her primary care physician complaining of worsening symptoms. She has been taking leflunomide. IL-1 and TNF-α are two key cytokines involved in the negative sequelae of rheumatoid arthritis. Which of the following drugs is a recombinant form of an endogenous IL-1 antagonist?
Correct Answer: B
Rationale: RA involves IL-1 and TNF-α driving inflammation. The question seeks a recombinant IL-1 antagonist. Abatacept inhibits T-cell costimulation, not IL-1. Anakinra , a recombinant IL-1 receptor antagonist (IL-1Ra), blocks IL-1 signaling, matching the description. Methotrexate slows cell proliferation, not an IL-1 antagonist. Hydroxychloroquine modulates immunity differently. Rituximab (E) targets B cells. Anakinra mimics natural IL-1Ra, reducing joint damage in RA when leflunomide fails, directly countering IL-1's effects, unlike broader or unrelated mechanisms of other options.
Question 5 of 5
A 24-year-old man is admitted for an emergent appendectomy. While in the operating room, the anesthesiologist finds that he must use a much higher than expected anesthetic dose to anesthetize this patient. After the surgery, the patient admits to barbiturate abuse. What is the correct term for the fact that his history of barbiturate abuse led to a greater anesthetic requirement?
Correct Answer: C
Rationale: Barbiturate abuse increases anesthetic need due to cross-tolerance . Chronic use induces enzymes and receptor changes, reducing anesthetic efficacy. Addiction , dependence , and cross-dependence don't explain dosing. Tolerance (E) is drug-specific. Cross-tolerance fits this scenario.