Levothyroxine is classified as which type of medication?
A. Synthetic thyroid hormone replacement
B. Loop diuretic
C. Sulfonylurea antidiabetic
D. Proton pump inhibitor
Show answer and reasoning
Correct answer: A. Synthetic thyroid hormone replacement
Correct. Levothyroxine is a synthetic form of the thyroid hormone thyroxine (T4), used to treat hypothyroidism by replacing deficient natural hormone.
- B: Loop diuretics, such as furosemide, promote fluid excretion via the kidney and are unrelated to thyroid hormone replacement.
- C: Sulfonylureas, such as glipizide, stimulate pancreatic insulin release; levothyroxine has no antidiabetic mechanism.
- D: Proton pump inhibitors, such as omeprazole, suppress gastric acid secretion and are unrelated to thyroid hormone therapy.
Source: PTCB PTCE Content Outline (Knowledge Area 1.0: Medications)
Which of the following is the generic name for the brand-name drug Xanax?
A. Lorazepam
B. Alprazolam
C. Diazepam
D. Clonazepam
Show answer and reasoning
Correct answer: B. Alprazolam
Correct. Xanax is the brand name for alprazolam, a short-acting benzodiazepine used to treat anxiety disorders.
- A: Lorazepam is a different benzodiazepine, marketed under the brand name Ativan, not Xanax.
- C: Diazepam is a different benzodiazepine, marketed under the brand name Valium, not Xanax.
- D: Clonazepam is a different benzodiazepine, marketed under the brand name Klonopin, not Xanax.
Source: PTCB PTCE Content Outline (Knowledge Area 1.0: Medications)
A patient stable on warfarin begins taking a new antibiotic, and the pharmacist flags the combination for an increased bleeding risk requiring closer INR monitoring. Which class of antibiotics is most classically associated with significantly potentiating warfarin's effect?
A. Topical antifungals applied to the skin
B. Inhaled bronchodilators
C. Fluoroquinolones and macrolides (e.g., ciprofloxacin, clarithromycin)
D. Topical ophthalmic antibiotic drops
Show answer and reasoning
Correct answer: C. Fluoroquinolones and macrolides (e.g., ciprofloxacin, clarithromycin)
Correct. Fluoroquinolones and macrolides are well documented to inhibit hepatic metabolism of warfarin (via CYP enzyme interactions) and alter gut flora that produce vitamin K, both of which can significantly raise INR and bleeding risk.
- A: Topical antifungals have minimal systemic absorption and are not classically associated with clinically significant warfarin interactions.
- B: Inhaled bronchodilators act locally in the lungs and have no established significant interaction with warfarin metabolism.
- D: Topical ophthalmic antibiotics have minimal systemic absorption and are not a classic warfarin interaction concern.
Source: PTCB PTCE Content Outline (Knowledge Area 1.0: Medications)
A common side effect of first-generation antihistamines like diphenhydramine, which is why they are used cautiously in elderly patients, is:
A. Hyperactivity and insomnia in nearly all patients
B. Significant weight loss
C. Hair growth stimulation
D. Sedation and anticholinergic effects (e.g., dry mouth, confusion, urinary retention)
Show answer and reasoning
Correct answer: D. Sedation and anticholinergic effects (e.g., dry mouth, confusion, urinary retention)
Correct. First-generation antihistamines cross the blood-brain barrier and have strong anticholinergic activity, causing sedation, dry mouth, blurred vision, constipation, and urinary retention, which is why the Beers Criteria flag them as high-risk in older adults.
- A: Sedation, not hyperactivity, is the classic effect of first-generation antihistamines, though a minority of patients (especially children) may experience paradoxical excitation.
- B: Weight loss is not a recognized common effect of diphenhydramine; sedating antihistamines are more commonly associated with increased appetite in some patients.
- C: Hair growth stimulation is not associated with diphenhydramine; it is a known effect of drugs like minoxidil, an unrelated medication class.
Source: PTCB PTCE Content Outline (Knowledge Area 1.0: Medications)
Once opened, an in-use insulin pen not requiring refrigeration by its labeling is generally stable at room temperature for approximately how long before it should be discarded?
A. About 28 days, though the exact duration varies by specific product labeling
B. Indefinitely, with no discard date
C. Only 24 hours
D. Up to 2 years
Show answer and reasoning
Correct answer: A. About 28 days, though the exact duration varies by specific product labeling
Correct. Most in-use insulin pens are labeled stable at room temperature for roughly 28 days after first use (some products vary, e.g., 10-56 days per manufacturer labeling), after which remaining product should be discarded even if insulin remains in the pen.
- B: In-use insulin has a finite stability window once opened; it is not indefinitely stable, unlike unopened, refrigerated vials.
- C: 24 hours drastically understates typical in-use insulin pen stability windows described in manufacturer labeling.
- D: 2 years is far beyond the in-use stability window; that duration would more closely resemble an unopened product's dating prior to first use, not an opened pen.
Source: PTCB PTCE Content Outline (Knowledge Area 1.0: Medications)
