Pharmacology Flashcards

What is the antidote for heparin overdose?

Answer: Protamine sulfate

Protamine sulfate is the specific antidote for heparin overdose. It binds to heparin and neutralizes its anticoagulant effect. The dose is 1 mg protamine for every 100 units of heparin, administered slowly IV. Vitamin K is the antidote for warfarin, not heparin.

What is the therapeutic INR range for a patient on warfarin therapy for atrial fibrillation?

Answer: 2.0-3.0

The therapeutic INR range for warfarin in atrial fibrillation is 2.0-3.0. Below 2.0 increases thromboembolic risk; above 3.0 increases bleeding risk. Higher ranges (2.5-3.5) are used for mechanical heart valves. Regular INR monitoring is essential.

Which vital sign must be assessed before administering digoxin?

Answer: Apical heart rate for one full minute

Apical heart rate must be counted for a full 60 seconds before digoxin administration. Hold the medication and notify the physician if the heart rate is below 60 bpm (adults) or below age-appropriate rates (pediatrics), as digoxin slows the heart rate.

What is the mechanism of action of ACE inhibitors like enalapril?

Answer: Block the conversion of angiotensin I to angiotensin II, reducing vasoconstriction and aldosterone secretion

ACE inhibitors block the angiotensin-converting enzyme, preventing formation of angiotensin II (a potent vasoconstrictor) and reducing aldosterone secretion (decreasing sodium and water retention). This lowers blood pressure and reduces cardiac workload.

What patient education should a nurse provide about metformin for type 2 diabetes?

Answer: Take with meals to reduce GI side effects, avoid excessive alcohol, report symptoms of lactic acidosis, and hold before contrast dye procedures

Metformin education: take with food (reduces GI effects), avoid excessive alcohol (increases lactic acidosis risk), report muscle pain/weakness/breathing difficulty (lactic acidosis signs), hold 48 hours before/after contrast dye, and monitor renal function regularly.

What is the nurse's primary concern when administering IV potassium chloride?

Answer: It must NEVER be given as an IV push — always diluted and infused slowly, with cardiac monitoring

IV potassium must NEVER be given as a bolus/push — it can cause fatal cardiac arrest. It must be diluted (typically 10-20 mEq/100 mL) and infused slowly (no faster than 10-20 mEq/hour). Cardiac monitoring is required for rates above 10 mEq/hour.