Free Missouri PTCB Practice Test Online

Correct answer: A. Penicillins

Correct. Amoxicillin is an aminopenicillin, part of the penicillin class of beta-lactam antibiotics.

• B: Macrolides include drugs like azithromycin and clarithromycin, a chemically distinct class from amoxicillin.
• C: Fluoroquinolones include drugs like ciprofloxacin and levofloxacin, a chemically distinct class from amoxicillin.
• D: Tetracyclines include drugs like doxycycline, a chemically distinct class from amoxicillin.

Correct answer: A. Biguanide antidiabetic (oral hypoglycemic)

Correct. Metformin is a biguanide, the first-line oral antidiabetic that decreases hepatic glucose production and improves insulin sensitivity.

• B: Sulfonylureas (e.g., glipizide, glyburide) stimulate insulin release from the pancreas; metformin works by a different mechanism and is not a sulfonylurea.
• C: Loop diuretics (e.g., furosemide) act on the kidney to promote fluid loss; metformin has no diuretic mechanism.
• D: ACE inhibitors (e.g., lisinopril) block angiotensin-converting enzyme for blood pressure control; metformin is unrelated to this drug class.

Correct answer: A. Atorvastatin

Correct. Lipitor is the brand name for atorvastatin, an HMG-CoA reductase inhibitor (statin) used to lower LDL cholesterol.

• B: Simvastatin is a different statin, marketed under the brand name Zocor, not Lipitor.
• C: Rosuvastatin is a different statin, marketed under the brand name Crestor, not Lipitor.
• D: Pravastatin is a different statin, marketed under the brand name Pravachol, not Lipitor.

Correct answer: A. Increased risk of bleeding

Correct. NSAIDs both impair platelet function and can displace warfarin from protein binding, and irritate the GI lining, compounding warfarin's anticoagulant effect and significantly raising bleeding risk.

• B: Hyperkalemia is a concern with drugs like ACE inhibitors or potassium-sparing diuretics, not the primary interaction risk between warfarin and NSAIDs.
• C: The concern is an increased, not decreased, anticoagulant/bleeding effect; NSAIDs do not meaningfully reduce warfarin absorption.
• D: Hypoglycemia relates to antidiabetic drug interactions, not the warfarin-NSAID interaction, which centers on bleeding risk.

Correct answer: A. A persistent dry cough

Correct. ACE inhibitors block the breakdown of bradykinin, and elevated bradykinin levels are associated with a persistent dry cough in a meaningful subset of patients, a well-known reason for switching to an ARB, which does not share this side effect.

• B: Weight gain is not a hallmark side effect of ACE inhibitors; it is more commonly associated with drugs like some antipsychotics, insulin, or corticosteroids.
• C: Severe constipation is not a typical ACE inhibitor side effect; it is more associated with opioids or certain anticholinergic drugs.
• D: Hair loss is not a recognized common side effect of ACE inhibitors.