ACE Inhibitors (-pril)
The "frill sisters" — first-line for HTN, heart failure, and diabetic nephropathy.
Suffix: -pril. Examples: lisinopril, enalapril, captopril, ramipril, benazepril
How They Work
Block the conversion of angiotensin I → angiotensin II → less vasoconstriction → less aldosterone release → lower BP and reduced cardiac workload.
Key Nursing Considerations
- Dry, persistent cough — the #1 side effect and reason patients switch to an ARB. Caused by bradykinin accumulation.
- Angioedema — swelling of face, lips, tongue, throat. This is a MEDICAL EMERGENCY — stop the drug, maintain airway, give epinephrine.
- Hyperkalemia — ACE inhibitors retain potassium. Monitor K⁺ levels. Do NOT give with potassium supplements or potassium-sparing diuretics without careful monitoring.
- Hypotension — especially first dose ("first-dose hypotension"). Monitor BP. Rise slowly.
- Monitor renal function — BUN/Cr. Renoprotective in diabetic patients but can worsen renal impairment.
- Contraindicated in pregnancy — teratogenic (causes fetal renal damage, especially 2nd/3rd trimester)
If a question says "patient on lisinopril develops a persistent dry cough" → the answer is notify the provider; the medication will likely be changed to an ARB (-sartan), which works similarly but does NOT cause cough. If the patient develops facial/tongue swelling → stop the drug immediately (angioedema).
Every key point in this guide fits on one free printable page. Jump to the free cheatsheet PDF →
ARBs (-sartan)
The ACE inhibitor alternative — same benefits, no cough.
Suffix: -sartan. Examples: losartan, valsartan, irbesartan, candesartan
How They Work
Block angiotensin II at the receptor level. Same endpoint as ACE inhibitors — lower BP, reduce cardiac workload — but through a different mechanism.
Key Points
- No dry cough — this is the main advantage over ACE inhibitors
- Still causes hyperkalemia — monitor K⁺
- Still contraindicated in pregnancy
- Still monitor renal function and BP
- First-dose hypotension can still occur
Both lower BP, protect kidneys, treat HF. Both cause hyperkalemia and are contraindicated in pregnancy. The difference: ACE inhibitors cause dry cough and angioedema risk. ARBs do NOT. If a patient can't tolerate an ACE inhibitor → switch to an ARB.
Beta-Blockers (-olol)
Slow the heart, lower the pressure — but check that HR first.
Suffix: -olol. Examples: metoprolol (Lopressor), atenolol (Tenormin), propranolol (Inderal), carvedilol (Coreg)
How They Work
Block beta-adrenergic receptors → decrease heart rate, decrease contractility, decrease BP, decrease cardiac workload. Used for HTN, heart failure, angina, arrhythmias, and MI.
Key Nursing Considerations
- Check HR and BP before every dose — hold per the ordered parameters (commonly HR <60 bpm or a low/symptomatic BP). Notify provider.
- NEVER stop abruptly — can cause rebound tachycardia, hypertension, angina, or even MI. Must taper over 1–2 weeks.
- Masks hypoglycemia in diabetic patients — beta-blockers suppress tachycardia (which is normally an early warning sign of low blood sugar). Teach diabetic patients to monitor glucose closely.
- Contraindicated in: severe bradycardia, heart block, uncompensated heart failure, asthma (can cause bronchospasm — especially non-selective like propranolol)
- Side effects: fatigue, dizziness, depression, sexual dysfunction, cold extremities
- Cardioselective (beta-1 only): metoprolol, atenolol — safer for patients with mild respiratory disease
- Non-selective (beta-1 + beta-2): propranolol — avoid in asthma/COPD (blocks beta-2 in lungs)
NEVER stop abruptly. If a patient tells you they ran out of their metoprolol and just stopped taking it → this is a safety concern. Abrupt discontinuation can trigger rebound hypertension, tachycardia, angina, or MI. Contact the provider immediately.
Calcium Channel Blockers (-dipine)
Two types: dihydropyridines (vessels) and non-dihydropyridines (heart).
Suffix: -dipine (for dihydropyridines). Examples: amlodipine, nifedipine
Non-dihydropyridines: diltiazem, verapamil (no shared suffix — memorize these two)
How They Work
Block calcium influx into cardiac and smooth muscle cells → vasodilation (lower BP) and/or decreased heart rate and contractility.
- Dihydropyridines (-dipine)Amlodipine, nifedipine
- Vasodilation (peripheral). Used for HTN. Minimal effect on heart rate.
- Non-dihydropyridinesDiltiazem, verapamil
- Slow HR + vasodilation. Used for HTN, angina, arrhythmias (A-fib rate control).
Key Nursing Considerations
- Peripheral edema — especially with dihydropyridines (amlodipine). Teach patient to elevate legs.
- No grapefruit juice — grapefruit increases drug levels (especially with verapamil) → risk of severe hypotension and cardiac arrest
- Constipation (especially verapamil)
- Monitor HR and BP — hold for bradycardia (non-dihydropyridines)
- Flushing, headache, dizziness from vasodilation
- Verapamil + beta-blocker = dangerous combination (both lower HR → severe bradycardia, heart block)
"A-Dip-ine = dips the vessels" — dihydropyridines (-dipine) primarily work on blood vessels (vasodilation). Diltiazem and verapamil work on the heart AND vessels (slow HR too). No grapefruit with any CCB.
Diuretics
Three types — and potassium is the key difference between them.
- Loop-semide · Furosemide, bumetanide
- LOSES K⁺ (hypokalemia). Most potent. Monitor K⁺, daily weights, I&O. Ototoxic at high doses. Give in AM (avoids nocturia).
- Thiazide-thiazide · HCTZ, chlorthalidone
- LOSES K⁺ (hypokalemia). First-line for HTN. Can increase blood glucose and uric acid. Photosensitivity. Less potent than loops.
- Potassium-SparingSpironolactone, triamterene, amiloride
- SAVES K⁺ (hyperkalemia risk). Do NOT give K⁺ supplements. Monitor K⁺. Spironolactone: may cause gynecomastia.
Universal Diuretic Nursing Care
- Daily weights — same time, same scale, same clothing. 1 kg = 1 liter of fluid.
- Strict I&O monitoring
- Monitor electrolytes (especially potassium)
- Monitor for dehydration: dry mucous membranes, poor skin turgor, tachycardia, hypotension
- Give in the morning (avoids nocturia/sleep disruption)
- Monitor BP — risk for orthostatic hypotension
Loop and thiazide diuretics = LOSE potassium → give K⁺-rich foods (bananas, oranges, potatoes) or supplements. Monitor for hypokalemia (weakness, leg cramps, irregular heartbeat). Potassium-sparing diuretics = SAVE potassium → AVOID extra K⁺. Monitor for hyperkalemia (peaked T waves, bradycardia). NEVER combine potassium supplements with potassium-sparing diuretics.
Hypokalemia (from loop/thiazide diuretics) INCREASES the risk of digoxin toxicity. Potassium and digoxin compete for the same binding sites. Low K⁺ → more digoxin binds → toxicity. Always check K⁺ when a patient is on both drugs.
Anticoagulants & Antiplatelets
The most tested drug comparison in nursing — heparin vs warfarin.
- HeparinIV/SubQ
- Onset: Immediate (IV). Lab: aPTT (1.5–2.5× normal). Antidote: Protamine sulfate. Special concern: HIT (Heparin-Induced Thrombocytopenia) — monitor platelets.
- Enoxaparin / LovenoxSubQ
- Onset: 3–5 hours. Lab: Usually none (anti-Xa if needed). Antidote: Protamine sulfate (partial). SubQ in abdomen. No aspiration, no massage.
- Warfarin / CoumadinPO
- Onset: 3–5 days for full effect. Lab: PT/INR (therapeutic: 2.0–3.0). Antidote: Vitamin K (phytonadione). Many food/drug interactions. Consistent vitamin K intake. Avoid leafy green fluctuations.
DOACs (Direct Oral Anticoagulants) — Newer Agents
Examples: rivaroxaban (Xarelto), apixaban (Eliquis), dabigatran (Pradaxa)
- Oral, fixed dose, fewer monitoring requirements (no routine INR/aPTT)
- Fewer food interactions than warfarin
- Antidotes: idarucizumab (Praxbind) for dabigatran; andexanet alfa (Andexxa) for rivaroxaban/apixaban
- Still monitor for bleeding
- Renal function must be adequate (excreted by kidneys)
Antiplatelets
- Aspirin — chew 325 mg during MI (antiplatelet effect). Low-dose (81 mg) daily for prevention. GI irritation, bleeding risk.
- Clopidogrel (Plavix) — used after stent placement, MI, stroke. Takes 5–7 days to clear. Hold before surgery.
Bleeding Precautions for ALL Anticoagulants
- Soft-bristle toothbrush, electric razor
- Avoid contact sports and activities that could cause injury
- Report: bleeding gums, nosebleeds, blood in urine/stool, excessive bruising, dark/tarry stools
- Wear a medical alert bracelet
- Avoid aspirin/NSAIDs (unless ordered) — increases bleeding risk
If a question asks "which lab monitors heparin?" → aPTT. "Which lab monitors warfarin?" → INR. If the INR is 5.0 → hold warfarin, notify provider (bleeding risk). If a patient on heparin has a sudden drop in platelets → think HIT → stop heparin immediately and notify the provider.
? A patient on warfarin reports eating large amounts of spinach every day this week. Why is this a concern?
Nitroglycerin
The angina drug — know the administration protocol and the #1 drug interaction.
How It Works
Vasodilator — relaxes vascular smooth muscle → dilates coronary arteries (improves blood flow to the heart) and veins (decreases preload). Relieves chest pain.
Administration Protocol (Sublingual)
Key Teaching Points
- Headache is the most common side effect (vasodilation) — expected, not dangerous
- Tablet should tingle/burn under the tongue — if it doesn't, the medication may have lost potency
- Store in a dark, glass container — light degrades the drug. Replace every 6 months.
- Keep away from heat and moisture
- Hold per the ordered parameters (commonly HR <60 or a low/symptomatic BP)
- Transdermal patches: apply to hairless area, rotate sites, remove old patch before applying new one. Remove patch at night for 10–12 hours (prevents tolerance — "nitrate-free interval").
Both cause vasodilation. Together they can cause severe, life-threatening hypotension. Do NOT give nitroglycerin if the patient has taken sildenafil (Viagra), tadalafil (Cialis), or vardenafil (Levitra) within the past 24–48 hours. This is one of the most commonly tested drug interactions on the exam.
Digoxin (Lanoxin)
Ranges vary by lab, facility, and textbook — for exams, use the range given in the question. See the full NCLEX-PN lab-value reference & sources →
The drug with more exam questions than any other single medication.
How It Works
Cardiac glycoside — increases the force of cardiac contraction (positive inotrope) and slows heart rate (negative chronotrope). Used for heart failure and atrial fibrillation.
Critical Nursing Actions
- Check apical pulse for 1 FULL MINUTE before every dose — hold if HR <60 bpm (adult), <70 (child), <90 (infant). Notify provider.
- Therapeutic level: 0.5–2.0 ng/mL — VERY narrow therapeutic window
- Monitor potassium — hypokalemia INCREASES digoxin toxicity risk (K⁺ and digoxin compete for the same binding sites). Always check K⁺.
Toxicity Signs (Must Know!)
- GI: nausea, vomiting, anorexia (often the FIRST signs)
- Visual: blurred vision, yellow-green halos around lights, photophobia
- Cardiac: bradycardia, heart block, dysrhythmias
- Neuro: fatigue, weakness, confusion
Antidote: Digibind (Digoxin Immune Fab)
Used for severe, life-threatening digoxin toxicity (lethal arrhythmias, K⁺ >5 mEq/L with digoxin toxicity).
Before giving digoxin, ask yourself 3 things: 1) Is the apical HR ≥60? 2) Is the potassium level normal (3.5–5.0)? 3) Is the digoxin level <2.0 ng/mL? If ANY answer is no → hold and notify the provider.
Antiarrhythmics
Know the big three: amiodarone, adenosine, and atropine.
- Amiodarone (Cordarone)A-Fib, V-Tach, V-Fib
- Very effective but VERY toxic. Monitor: pulmonary toxicity (CXR, lung function), thyroid dysfunction (hypo or hyper), liver toxicity (LFTs), corneal deposits (eye exams), photosensitivity (sunscreen, protective clothing). Turns skin blue-gray with long-term use. Multiple drug interactions.
- Adenosine (Adenocard)SVT
- Given rapid IV push followed by NS flush. Causes brief asystole (3–6 seconds) — warn the patient they may feel a "thud" or chest tightness. Monitor with continuous telemetry. Have crash cart available.
- AtropineSymptomatic bradycardia
- Increases heart rate by blocking vagal (parasympathetic) stimulation. Anticholinergic side effects: dry mouth, urinary retention, constipation, blurred vision. Also used as antidote for organophosphate poisoning.
- LidocaineVentricular arrhythmias
- Given IV during cardiac emergencies (V-Tach). Monitor for CNS toxicity: tinnitus, confusion, tremors, seizures. Also used as a local anesthetic.
If a question mentions a patient on amiodarone with new-onset shortness of breath → think pulmonary toxicity. New thyroid symptoms → thyroid dysfunction. Elevated LFTs → hepatotoxicity. Corneal deposits → blurred vision. This drug affects almost every organ system — that's why it requires extensive monitoring.
Statins & Cholesterol Drugs
Suffix: -statin. Take at bedtime, and always ask about muscle pain.
Suffix: -statin. Examples: atorvastatin (Lipitor), simvastatin (Zocor), rosuvastatin (Crestor), pravastatin
How They Work
Inhibit HMG-CoA reductase → decrease cholesterol production in the liver → lower LDL ("bad" cholesterol), raise HDL ("good" cholesterol), lower triglycerides.
Key Nursing Considerations
- Take at bedtime — cholesterol synthesis peaks at night (though atorvastatin and rosuvastatin can be taken any time due to long half-lives)
- Report muscle pain immediately — can indicate rhabdomyolysis (breakdown of muscle tissue → myoglobin release → kidney damage). Check CK levels if suspected.
- Monitor liver function (LFTs) — hepatotoxicity risk. Baseline and periodic monitoring.
- Avoid excessive alcohol (additive liver damage)
- Avoid grapefruit juice (increases drug levels with certain statins)
- Contraindicated in pregnancy (teratogenic)
Target Cholesterol Values
- Total cholesterol
- <200 mg/dL
- LDL ("bad")
- <100 mg/dL (optimal)
- HDL ("good")
- >40 mg/dL (male), >50 mg/dL (female)
- Triglycerides
- <150 mg/dL
LDL = "Lousy" cholesterol (you want it LOW). HDL = "Happy/Healthy" cholesterol (you want it HIGH). Statins primarily lower LDL. Diet + exercise help raise HDL.
Heart Failure Drug Regimen
The standard drug combination for HF — know why each one is used.
Heart failure management typically involves a combination of drug classes. Each targets a different mechanism to reduce symptoms, improve cardiac output, and prolong life.
- ACE InhibitorLisinopril
- Reduces afterload (vasodilation) and prevents remodeling. Monitor: BP, K⁺, renal function, cough.
- Beta-BlockerCarvedilol, metoprolol succinate
- Reduces HR and cardiac workload, prevents remodeling. Monitor: HR (>60), BP (>90 systolic). Start low, go slow.
- Loop DiureticFurosemide
- Removes excess fluid (reduces preload and edema). Monitor: daily weights, K⁺, I&O, dehydration signs.
- Digoxin
- Increases contractility, slows HR. Monitor: apical pulse ×1 min, K⁺, dig level (0.5–2.0).
- Aldosterone AntagonistSpironolactone
- Mild diuretic, blocks aldosterone, saves K⁺. Monitor: K⁺ (hyperkalemia risk), renal function.
- Vasodilator (PRN)Hydralazine + Isosorbide dinitrate
- Alternative if ACE/ARB not tolerated. Reduces preload and afterload. Monitor: BP, headache, reflex tachycardia.
Daily weights (report 2 lbs/day or 5 lbs/week gain), low-sodium diet (≤2,000 mg), fluid restriction (1.5–2 L/day), take meds consistently, avoid NSAIDs (fluid retention, worsens HF), elevate HOB for breathing, and activity as tolerated with rest periods.
Frequently Asked Questions
Common student questions on this topic.
What is the difference between ACE inhibitors and ARBs?
How are beta blockers different from calcium channel blockers?
Why should you hold digoxin if the apical pulse is low?
What is the difference between heparin and warfarin?
What are the signs of digoxin toxicity?
How do statins work and what side effect should I monitor for?
Quick-Reference Cheatsheet
Every key point from this guide on a single printable page.
Cardiovascular Medications Cheatsheet
Free, printable PDF · no spam · returning visitors skip the email step.