Pharmacology Exam Review: Cardiovascular and Urinary Medications

Medications Affecting Blood Pressure

• Hydrochlorothiazide (Microzide) — Thiazide Diuretic

  • Purpose: Effectively lowers blood pressure and treats conditions related to fluid overload.
  • Adverse and Side Effects: Risks include hypokalemia ($low\,K^+$), hyponatremia ($low\,Na^+$), hyperglycemia ($high\,glucose$), gout, and increased sensitivity to the sun.
  • Interactions: Use with Digoxin increases the risk of digoxin toxicity due to hypokalemia. Use with Lithium can result in increased lithium levels.
  • Antidote: No specific antidote identified.
  • Nursing Focus: Medications should be administered in the morning ($AM$). Monitor potassium ($K^+$) levels closely. Patients must be taught to report leg cramps or muscle spasms, which are indicators of low potassium.
  • Test Alert: Leg cramps and muscle spasms indicate suspected hypokalemia ($K^+ < 3.5$).

• Captopril / Lisinopril (Capoten/Zestril) — ACE Inhibitor

  • Purpose: Indicated for hypertension and heart failure management.
  • Adverse and Side Effects: Characterized by a dry cough, hyperkalemia ($high\,K^+$), hypotension ($low\,BP$), and angioedema.
  • Interactions: Potassium supplements or potassium-sparing diuretics may dangerously elevate potassium. NSAIDs can reduce the effectiveness of the drug.
  • Antidote: No specific antidote. For angioedema, the drug must be stopped, and the airway must be supported.
  • Nursing Focus: Monitor potassium levels and renal function. Instruct patients to report any facial or tongue swelling immediately. Contraindicated during pregnancy.
  • Test Alert: This is the serious persistent cough drug; this cough can potentially progress to urgent angioedema.

• Losartan / Valsartan (Cozaar/Diovan) — Angiotensin II Receptor Blocker (ARB)

  • Purpose: Used for hypertension and heart failure.
  • Adverse and Side Effects: Includes hyperkalemia ($high\,K^+$), dizziness, and hypotension ($low\,BP$).
  • Interactions: Potassium supplements and salt substitutes may further increase potassium levels.
  • Antidote: No specific antidote.
  • Nursing Focus: Monitor potassium levels. Advise patients to avoid salt substitutes and potassium supplements. Never use during pregnancy.
  • Test Alert: ARBs do not cause the cough or angioedema seen with ACE inhibitors; this is the primary way to differentiate the two classes.

• Aliskiren (Tekturna) — Direct Renin Inhibitor

  • Purpose: Hypertension treatment.
  • Adverse and Side Effects: High potassium ($high\,K^+$), dizziness, and low blood pressure ($low\,BP$).
  • Interactions: Avoid combining with ACE inhibitors or ARBs as this increases the risk of hyperkalemia and renal damage.
  • Antidote: No specific antidote.
  • Nursing Focus: Monitor potassium levels. Never use during pregnancy.
  • Test Alert: This drug blocks renin at the very top of the Renin-Angiotensin-Aldosterone System ($RAAS$) pathway.

• Nifedipine (Procardia XL) — Calcium Channel Blocker (Dihydropyridine)

  • Purpose: Hypertension and chest pain management.
  • Adverse and Side Effects: Ankle edema, flushing, headache, and reflex tachycardia.
  • Interactions: Grapefruit juice must be avoided as it raises drug levels.
  • Antidote: No specific antidote.
  • Nursing Focus: Educate the patient that edema results from vasodilation, not fluid overload, meaning a diuretic will not resolve the swelling.
  • Test Alert: Reflex tachycardia is the definitive exam clue for nifedipine.

• Verapamil (Calan/Verelan) — Calcium Channel Blocker (Non-dihydropyridine)

  • Purpose: Treats hypertension and arrhythmias.
  • Adverse and Side Effects: Low heart rate ($low\,HR$), constipation, and hypotension ($low\,BP$).
  • Interactions: Avoid combining with beta blockers or digoxin due to the risk of additive bradycardia or AV block.
  • Antidote: No specific antidote.
  • Nursing Focus: Check the apical pulse first; hold the medication if the pulse is $< 60$.
  • Test Alert: Causes bradycardia, unlike the reflex tachycardia associated with nifedipine.

• Diltiazem (Cardizem) — Calcium Channel Blocker (Non-dihydropyridine)

  • Purpose: Used for hypertension, arrhythmias, and chest pain.
  • Adverse and Side Effects: Low heart rate ($low\,HR$), low blood pressure ($low\,BP$), and headache.
  • Interactions: Avoid grapefruit juice. Exercise caution when combined with beta blockers or digoxin.
  • Antidote: No specific antidote.
  • Nursing Focus: Check the pulse first and hold the dose if it is $< 60$.
  • Test Alert: Shares the same bradycardia caution as verapamil.

• Metoprolol (Lopressor/Toprol XL) — Beta-1 Selective Blocker

  • Purpose: Hypertension, chest pain, arrhythmias (including SVT), and heart failure.
  • Adverse and Side Effects: Low heart rate ($low\,HR$), fatigue, masking of hypoglycemia symptoms, and hypotension ($low\,BP$).
  • Interactions: Avoid combination with other heart-rate-lowering drugs like verapamil, diltiazem, or digoxin without close monitoring.
  • Antidote: No specific antidote, though glucagon may support severe overdose in acute care settings.
  • Nursing Focus: Check the pulse first and hold if $< 60$. Never discontinue abruptly; it must be tapered.
  • Test Alert: Hides hypoglycemia warning signs in diabetic patients and is contraindicated/risky with asthma.

• Propranolol (Inderal) — Nonselective Beta Blocker

  • Purpose: Hypertension, arrhythmias, migraine prevention, and tremors.
  • Adverse and Side Effects: Low heart rate ($low\,HR$), wheezing, hypotension ($low\,BP$), and orthostatic hypotension.
  • Interactions: Avoid in patients with asthma or COPD because it blocks protective beta-$2$ receptors.
  • Antidote: No specific antidote.
  • Nursing Focus: Teach the patient to rise slowly and check their pulse daily. Never discontinue abruptly.
  • Test Alert: New wheezing plus shortness of breath ($SOB$) indicates bronchospasm and must be treated as an $ABC$ (Airway, Breathing, Circulation) priority.

• Carvedilol (Coreg) — Alpha-1 and Beta-1/2 Blocker

  • Purpose: Heart failure and hypertension.
  • Adverse and Side Effects: Dizziness, low heart rate ($low\,HR$), hypotension ($low\,BP$), and fatigue.
  • Interactions: Additive hypotension when used with other vasodilators.
  • Antidote: No specific antidote.
  • Nursing Focus: Administer with food to reduce dizziness. Check vital signs before dosing.
  • Test Alert: By blocking both alpha and beta receptors, it drops blood pressure more significantly than typical beta blockers.

• Sodium Nitroprusside (Nitropress) — Direct Vasodilator

  • Purpose: Hypertensive emergency.
  • Adverse and Side Effects: Severe hypotension and cyanide toxicity with prolonged usage.
  • Interactions: Additive hypotension with other antihypertensive agents.
  • Antidote: For cyanide toxicity, use sodium thiosulfate or hydroxocobalamin per protocol.
  • Nursing Focus: Administer via IV only. The bag and tubing must be protected from light, often requiring a glass bottle. Continuous blood pressure monitoring with an arterial line is required.
  • Test Alert: The liver metabolizes this drug into cyanide, which the kidneys must then clear.

• Eplerenone (Inspra) — Aldosterone Antagonist (K+-Sparing)

  • Purpose: Hypertension and heart failure.
  • Adverse and Side Effects: Hyperkalemia ($high\,K^+$), dizziness, and low blood pressure ($low\,BP$).
  • Interactions: Avoid potassium supplements and salt substitutes. Exercise caution with ACE inhibitors/ARBs to avoid stacking hyperkalemia risks.
  • Antidote: No specific antidote.
  • Nursing Focus: Monitor potassium levels closely and avoid high-potassium foods.
  • Test Alert: Do not confuse this medication with milrinone, which is a different drug and class.

Cardiac Glycosides, Heart Failure & Vasopressors

• Epinephrine (Adrenalin) — Adrenergic Agonist / Vasopressor

  • Purpose: Cardiac arrest ($ACLS$), anaphylaxis, and asthma emergencies.
  • Adverse and Side Effects: Rapid heart rate ($fast\,HR$), high blood pressure ($high\,BP$), anxiety, tremors, and hyperglycemia.
  • Interactions: Additive effects with other vasopressors.
  • Antidote: No specific antidote.
  • Nursing Focus: For anaphylaxis, administer $IM$ in the thigh. Monitor ECG and blood pressure closely.
  • Test Alert: Epinephrine is administered every $2$ minutes during CPR. Hyperglycemia is not considered the priority in a code situation.

• Norepinephrine (Levophed) — Vasopressor

  • Purpose: Severe hypotension and septic shock.
  • Adverse and Side Effects: Severe hypertension, reflex bradycardia, and tissue damage if IV extravasation occurs.
  • Interactions: Additive effects with other vasopressors.
  • Antidote: Phentolamine is used for extravasation.
  • Nursing Focus: Administer through a central line. Inspect the IV site frequently.
  • Test Alert: This is a vasopressor used to support blood pressure and vascular tone in critical care.

• Dopamine — Vasopressor

  • Purpose: Treatment for shock and low cardiac output.
  • Adverse and Side Effects: Irregular heartbeat, high blood pressure, and nausea.
  • Interactions: Additive effects with other vasopressors.
  • Antidote: No specific antidote.
  • Nursing Focus: Titrate based on weight-based dosages. Monitor ECG, blood pressure, and urine output.
  • Test Alert: The effect of dopamine changes with the dose: low doses affect renal perfusion, while high doses cause vasoconstriction.

• Dobutamine (Dobutrex) — Beta-1 Agonist / Inotrope

  • Purpose: Cardiogenic shock and short-term heart failure management.
  • Adverse and Side Effects: Fast heart rate ($fast\,HR$), irregular heartbeat, chest pain, and low blood pressure ($low\,BP$).
  • Interactions: Additive effects with other vasopressors or inotropes.
  • Antidote: No specific antidote.
  • Nursing Focus: Requires continuous ECG and blood pressure monitoring.
  • Test Alert: Provides short-term inotropic support in critical care settings.

• Sacubitril/Valsartan (Entresto) — ARNI (Combination Drug)

  • Purpose: Heart failure.
  • Adverse and Side Effects: Low blood pressure, high potassium, and angioedema.
  • Interactions: NEVER combine with an ACE inhibitor. A $36$-hour washout period is required when switching between these drugs to avoid serious angioedema risk.
  • Antidote: No specific antidote.
  • Nursing Focus: Teach the $36$-hour rule. Monitor potassium and blood pressure.
  • Test Alert: An ARNI consists of a neprilysin inhibitor and an ARB.

• Digoxin (Lanoxin) — Cardiac Glycoside

  • Purpose: Heart failure and atrial fibrillation.
  • Adverse and Side Effects: Nausea/Vomiting ($N/V$), anorexia, visual disturbances (yellow/green halos), confusion, and new arrhythmias.
  • Interactions: Loop and thiazide diuretics increase toxicity risk via hypokalemia. Amiodarone raises digoxin levels.
  • Antidote: Digoxin immune Fab (Digibind/DigiFab) for severe toxicity.
  • Nursing Focus: Check the apical pulse for $1$ full minute before chaque dose; hold if the pulse is $< 60$. Monitor potassium levels.
  • Test Alert: The therapeutic range is generally $0.6-1.2$, though instructors may specify a range of $0.5-2.0$.

Medications Affecting Urinary Output

• Furosemide (Lasix) — Loop Diuretic

  • Purpose: Fluid overload, heart failure, and hypertension.
  • Adverse and Side Effects: Hypokalemia ($low\,K^+$), hyponatremia ($low\,Na^+$), hearing damage (ototoxicity), low blood pressure, and gout.
  • Interactions: Hypokalemia increases digoxin toxicity risk. Ototoxic drugs like aminoglycosides stack hearing risks.
  • Antidote: No specific antidote.
  • Nursing Focus: Administer IV doses slowly. Give in the morning ($AM$). Monitor potassium and hearing status.
  • Test Alert: Monitor potassium closely, especially if the patient is also taking digoxin.

• Spironolactone (Aldactone) — Potassium-Sparing Diuretic

  • Purpose: Heart failure, hypertension, and fluid buildup.
  • Adverse and Side Effects: Hyperkalemia ($high\,K^+$), breast enlargement in men (gynecomastia), and menstrual changes.
  • Interactions: Avoid potassium supplements and salt substitutes. Exercise caution with ACE inhibitors/ARBs.
  • Antidote: No specific antidote.
  • Nursing Focus: Monitor potassium levels closely.
  • Test Alert: This drug is the opposite of loop/thiazide diuretics because it raises potassium levels.

• Mannitol (Osmitrol) — Osmotic Diuretic

  • Purpose: Brain swelling, high intracranial pressure, and eye pressure.
  • Adverse and Side Effects: Initial fluid overload and risk of IV crystallization.
  • Interactions: Avoid in cases of active brain bleeding or severe heart failure.
  • Antidote: No specific antidote.
  • Nursing Focus: Use a filter needle for administration. Monitor neurological status and fluid balance.
  • Test Alert: Mannitol can briefly worsen heart failure before the diuretic effect begins.

Antianginal & Lipid-Lowering Agents

• Nitroglycerin (Nitrostat/Nitro-Dur) — Organic Nitrate

  • Purpose: Treatment of angina (chest pain).
  • Adverse and Side Effects: Headache, hypotension ($low\,BP$), reflex tachycardia, and flushing.
  • Interactions: NEVER combine with erectile dysfunction (ED) drugs as this causes severe, life-threatening hypotension.
  • Antidote: No specific antidote.
  • Nursing Focus: Patients should sit or lie down before administration. Doses may be repeated every $5$ minutes for up to $3$ total doses. Call $911$ if pain remains unrelieved.
  • Test Alert: The severe hypotension risk with ED drugs is a critical point.

• Ranolazine (Ranexa) — Antianginal

  • Purpose: Chronic angina.
  • Adverse and Side Effects: Prolonged $QT$ interval, dizziness, and constipation.
  • Interactions: Caution with other drugs that prolong the $QT$ interval.
  • Antidote: No specific antidote.
  • Nursing Focus: Monitor ECG. Note that it does not significantly change heart rate or blood pressure.
  • Test Alert: It is an add-on drug that lacks significant effect on heart rate and blood pressure.

• Atorvastatin (Lipitor) — Statin

  • Purpose: Management of high cholesterol.
  • Adverse and Side Effects: Muscle pain that can progress to rhabdomyolysis and liver damage.
  • Interactions: Avoid grapefruit juice as it increases drug levels and toxicity risk.
  • Antidote: No specific antidote.
  • Nursing Focus: Patients must report unexplained muscle pain or dark urine. Contraindicated in pregnancy.
  • Test Alert: Statins and grapefruit juice are a classic pairing for examination questions.

• Ezetimibe (Zetia) — Cholesterol Absorption Inhibitor

  • Purpose: High cholesterol.
  • Adverse and Side Effects: Mild GI upset and rare liver effects.
  • Interactions: Often combined with statins; check for added liver or muscle risks.
  • Antidote: No specific antidote.
  • Nursing Focus: Often paired with statins for additional LDL reduction.
  • Test Alert: This works in the gut, using a different mechanism than statins.

• Colesevelam (Welchol) — Bile Acid Sequestrant

  • Purpose: High cholesterol.
  • Adverse and Side Effects: Constipation, bloating, and gas.
  • Interactions: Blocks the absorption of many oral drugs and fat-soluble vitamins ($A$, $D$, $E$, $K$).
  • Antidote: No specific antidote.
  • Nursing Focus: Other medications must be taken $1$ hour before or $4-6$ hours after colesevelam.
  • Test Alert: Timing with other oral medications is critical.

• Alirocumab (Praluent) — PCSK9 Inhibitor

  • Purpose: High cholesterol not controlled by other medications.
  • Adverse and Side Effects: Injection site reactions and rare allergic reactions.
  • Interactions: Few significant interactions.
  • Antidote: No specific antidote.
  • Nursing Focus: Administered by subcutaneous injection; nursing should teach injection technique.
  • Test Alert: Lowers LDL directly through a mechanism different from statins.

Medications Affecting Cardiac Rhythm

• Quinidine — Class IA Antiarrhythmic

  • Purpose: Various arrhythmias.
  • Adverse and Side Effects: GI upset, tinnitus, confusion, dizziness, and prolonged $QT$.
  • Interactions: May increase digoxin levels.
  • Antidote: No specific antidote.
  • Nursing Focus: Monitor ECG and $QT$ interval. Hold and notify the provider if toxicity signs appear.
  • Test Alert: The combination of tinnitus, confusion, and dizziness indicates toxicity.

• Lidocaine (Xylocaine) — Class IB Antiarrhythmic

  • Purpose: Life-threatening ventricular arrhythmias, including V-fib and V-tach with a pulse.
  • Adverse and Side Effects: Perioral tingling or numbness, slight hand tremors, and drowsiness.
  • Interactions: Caution with other liver-metabolized drugs.
  • Antidote: No specific antidote.
  • Nursing Focus: Actively ask awake patients about toxicity symptoms and monitor rhythm.
  • Test Alert: Early toxicity includes perioral tingling, tremors, and drowsiness, which can progress to seizures and cardiac arrest.

• Propafenone (Rythmol) — Class IC Antiarrhythmic

  • Purpose: Atrial and ventricular arrhythmias.
  • Adverse and Side Effects: Dizziness, metallic taste, and proarrhythmic effects (can worsen arrhythmias).
  • Interactions: Avoid in structural heart disease.
  • Antidote: No specific antidote.
  • Nursing Focus: Monitor ECG closely.
  • Test Alert: It is proarrhythmic and can cause the very condition it is meant to treat.

• Flecainide (Tambocor) — Class IC Antiarrhythmic

  • Purpose: Atrial and ventricular arrhythmias.
  • Adverse and Side Effects: Dizziness, blurred vision, and proarrhythmic effects.
  • Interactions: Avoid in structural heart disease.
  • Antidote: No specific antidote.
  • Nursing Focus: Monitor the EKG specifically for a wide $QRS$ complex.
  • Test Alert: A wide $QRS$ complex on an EKG is the classic flecainide clue.

• Amiodarone (Cordarone/Pacerone) — Class III Antiarrhythmic

  • Purpose: Serious ventricular arrhythmias (V-fib, pulseless V-tach, and code situations).
  • Adverse and Side Effects: Lung scarring, thyroid issues, liver damage, corneal eye deposits, blue-gray skin, cough, and increased respiratory rate.
  • Interactions: DO NOT consume grapefruit juice. Amiodarone raises levels of digoxin and warfarin.
  • Antidote: No specific antidote.
  • Nursing Focus: Obtain baseline and routine chest x-rays, thyroid tests, liver tests, and eye exams.
  • Test Alert: No grapefruit juice ever; watch for a new cough or increased respiratory rate ($RR$).

• Adenosine (Adenocard) — SVT Reset Drug

  • Purpose: Terminates Supraventricular Tachycardia ($SVT$).
  • Adverse and Side Effects: Causes a brief pause in heartbeat (asystole for a few seconds), flushing, chest pressure, and low blood pressure.
  • Interactions: Few significant interactions due to single-dose emergency use.
  • Antidote: No specific antidote.
  • Nursing Focus: Administer as a rapid IV push immediately followed by a saline flush. Resuscitation equipment must be nearby.
  • Test Alert: Brief asystole is an expected effect, not a complication.

• Atropine (Atropen) — Anticholinergic

  • Purpose: Symptomatic bradycardia.
  • Adverse and Side Effects: Dry mouth, blurred vision, urinary retention, and tachycardia.
  • Interactions: Additive anticholinergic effects with other anticholinergic drugs.
  • Antidote: Atropine serves as the antidote for cholinergic toxicity.
  • Nursing Focus: Monitor heart rate response post-administration.
  • Test Alert: Speeds the heart rate up, which is the opposite goal of most other cardiac drugs.

Medications Affecting Cardiac Coagulation

• Heparin (Unfractionated)

  • Purpose: Prevents and treats blood clots.
  • Adverse and Side Effects: Bleeding and heparin-induced thrombocytopenia ($HIT$), which is a drop in platelet count.
  • Interactions: Additive bleeding risk with other anticoagulants, antiplatelets, and NSAIDs.
  • Antidote: Protamine sulfate.
  • Nursing Focus: Monitor aPTT and platelet counts.
  • Test Alert: If $HIT$ develops, the patient must switch to Argatroban.

• Enoxaparin (Lovenox) — Low Molecular Weight Heparin

  • Purpose: Prevents and treats blood clots.
  • Adverse and Side Effects: Bleeding and injection site bruising.
  • Interactions: Additive bleeding risk with other anticoagulants.
  • Antidote: Protamine sulfate provides partial reversal.
  • Nursing Focus: Administered subcutaneously with less lab monitoring required than heparin.
  • Test Alert: This is considered a 'cousin' of heparin.

• Fondaparinux (Arixtra)

  • Purpose: Clot prevention and treatment.
  • Adverse and Side Effects: Bleeding.
  • Interactions: Additive bleeding risk with other anticoagulants.
  • Antidote: No reliable antidote.
  • Nursing Focus: Exercise caution in renal impairment as it is cleared by the kidneys.
  • Test Alert: It is a non-heparin option but is not the first-line choice for $HIT$ specifically.

• Warfarin (Coumadin/Jantoven) — Vitamin K Antagonist

  • Purpose: Long-term clot prevention.
  • Adverse and Side Effects: Bleeding and bruising.
  • Interactions: Numerous drug and food interactions. Amiodarone raises levels. Vitamin K-rich foods like spinach, kale, and broccoli lower effectiveness.
  • Antidote: Vitamin K (phytonadione).
  • Nursing Focus: Monitor INR. Maintain consistent vitamin K intake (not necessarily low). Contraindicated in pregnancy.
  • Test Alert: Warfarin is monitored by $INR$ ($2.0-3.0$), not by a specific drug level.

• Dabigatran (Pradaxa) — Oral Direct Thrombin Inhibitor

  • Purpose: Stroke and blood clot prevention.
  • Adverse and Side Effects: Bleeding and GI upset.
  • Interactions: Additive bleeding risk with other anticoagulants.
  • Antidote: Idarucizumab (Praxbind).
  • Nursing Focus: No routine INR monitoring is needed. Use caution in renal impairment.
  • Test Alert: One of the few anticoagulants with a specific reversal agent.

• Argatroban — IV Direct Thrombin Inhibitor

  • Purpose: Prevents clots when heparin cannot be used due to a history of $HIT$.
  • Adverse and Side Effects: Bleeding.
  • Interactions: Additive bleeding risk with other anticoagulants.
  • Antidote: No antidote.
  • Nursing Focus: Given by continuous IV; requires close monitoring.
  • Test Alert: THE classic 'instead of heparin' answer for patients with $HIT$.

• Rivaroxaban (Xarelto) — Oral Factor Xa Inhibitor

  • Purpose: Blood clot prevention.
  • Adverse and Side Effects: Bleeding.
  • Interactions: Additive bleeding risk with other anticoagulants.
  • Antidote: Andexanet alfa (where available).
  • Nursing Focus: No routine blood monitoring is needed. Features fewer food interactions than warfarin.
  • Test Alert: Non-heparin oral option, but not first-line for $HIT$ specifically.

• Clopidogrel (Plavix) — Antiplatelet

  • Purpose: Clot prevention, often following stent placement or stroke.
  • Adverse and Side Effects: Bleeding, bruising, and GI upset.
  • Interactions: Additive bleeding risk with other anticoagulants/antiplatelets. Certain proton pump inhibitors reduce efficacy.
  • Antidote: No specific antidote (platelet transfusion may be used for severe bleeding).
  • Nursing Focus: Take with food for GI upset. Must be discontinued before surgery as directed.
  • Test Alert: This is an antiplatelet, not an anticoagulant, which is a different mechanism.

• Alteplase (Activase/tPA) — Thrombolytic

  • Purpose: Dissolves existing clots (stroke, massive PE, acute MI).
  • Adverse and Side Effects: Major bleeding risk, particularly intracranial bleeding.
  • Interactions: Extreme caution required if the patient is on any other anticoagulants or antiplatelets.
  • Antidote: No specific antidote; supportive care and blood products/cryoprecipitate may be needed.
  • Nursing Focus: Strict time windows and inclusion criteria apply. Monitor neuro status and vital signs very closely after administration.
  • Test Alert: The only drug in this list that dissolves an existing clot; it carries the highest bleeding risk.