Km value indicates
- A. Purity of enzyme
- B. Physiological role
- C. Half life enzyme drug complex
- D. Affinity
Correct Answer: C
Rationale: Km (Michaelis constant) reflects the substrate concentration at half-maximum velocity, indicating enzyme-drug complex half-life.
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A nurse working in radiology administers iodine to a patient who is having a computerized axial tomography (CAT) scan. A nurse working on an oncology unit administers chemotherapy to patients who have cancer. At the Public Health Department, a nurse administers a measles-mumps-rubella (MMR) vaccine to a 14month-old child as a routine immunization. Which branch of pharmacology best describes the actions of all three nurses?
- A. Pharmacoeconomics
- B. Pharmacotherapeutics
- C. Pharmacodynamics
- D. Pharmacokinetics
Correct Answer: B
Rationale: Pharmacology is the study of the biologic effects of chemicals. Nurses are involved with clinical pharmacology or pharmacotherapeutics, which is a branch of pharmacology that deals with the uses of drugs to treat, prevent, and diagnose disease. The nurse working in radiology is administering a drug to help diagnose a disease. The nurse working on an oncology unit is administering a drug to help treat a disease. Pharmacoeconomics includes any costs involved in drug therapy. Pharmacodynamics involves how a drug affects the body, and pharmacokinetics is how the body acts on the drug.
Off-label prescribing is:
- A. Regulated by the U.S. Food and Drug Administration
- B. Illegal by NPs in all states (provinces)
- C. Legal if there is scientific evidence for the use
- D. Regulated by the Drug Enforcement Administration
Correct Answer: C
Rationale: Off-label prescribing is legal with scientific support , not FDA-regulated , universally illegal , or DEA-controlled .
Carbamazepine has a Black Box Warning due to life-threatening:
- A. Renal toxicity, leading to renal failure
- B. Hepatotoxicity, leading to liver failure
- C. Dermatologic reaction, including Steven's Johnson and toxic epidermal necrolysis
- D. Cardiac effects, including supraventricular tachycardia
Correct Answer: C
Rationale: Carbamazepine's Black Box Warning highlights severe skin reactions like SJS/TEN.
Combined alpha-beta antagonists are used to reduce the progression of heart failure because they:
- A. Vasodilate the peripheral vasculature
- B. Decrease cardiac output
- C. Increase renal vascular resistance
- D. Reduce atherosclerosis secondary to elevated serum lipoproteins
Correct Answer: A
Rationale: Alpha-beta blockers (e.g., carvedilol) vasodilate, reducing afterload in heart failure.
The nurse is caring for a patient who had a severe, acute, previously unseen adverse effect of a drug in Phase III testing. The patient asks, After all the testing done on this drug, didnt they know this adverse effect could occur? What is the nurses best response? (Select all that apply.)
- A. Phase III testing involves wide-scale population testing, which can reveal rare adverse effects not seen in earlier phases.
- B. New adverse effects can lead to further study or withdrawal of the drug.
- C. Phase I testing on healthy volunteers ensures all adverse effects are identified before patient use.
- D. Even with extensive testing, some adverse effects may only appear after widespread use.
Correct Answer: C
Rationale: Phase III testing involves a large population, uncovering rare effects . Preclinical animal studies don't fully predict human responses (B is false). Phase I uses healthy volunteers, missing disease-specific effects (C is false). Rare effects emerge post-approval , potentially leading to further action .