Pharmacology Essentials: Drug Classes & Clinical Insights
Antihypertensive Medications
ACE Inhibitors: Lisinopril
MOA: Blocks conversion of Angiotensin I to II, leading to vasodilation and decreased blood pressure.
Effects: Decreases preload and afterload, prevents cardiac remodeling.
Uses: Hypertension (HTN), heart failure, post-myocardial infarction (MI), diabetic nephropathy.
Adverse Effects:
⚠️ Black Box Warning: Fetal injury
Common: Cough, hyperkalemia, angioedema, first-dose hypotension, dizziness.Avoid: Diuretics (increased risk of hypotension), potassium-sparing drugs, lithium.
Hint: Medications ending in -pril (e.g., Lisinopril) Lower Pressure + Less Aldosterone = Less Volume.
Beta Blockers: Propranolol
MOA: Blocks beta-1 and beta-2 receptors, decreasing heart rate, contractility, and AV node conduction.
Uses: Hypertension (HTN), arrhythmias, anxiety.
Adverse Effects:
⚠️ Black Box Warning: Do NOT stop suddenly (risk of rebound hypertension).
Common: Bradycardia, heart block, hypotension, masks hypoglycemia.
Contraindication: Avoid in asthma/COPD due to bronchospasm risk.Hint: Medications ending in -lol (e.g., Propranolol) Lowers Output & Lowers Nerves.
Calcium Channel Blockers: Nifedipine
MOA: Blocks calcium influx into smooth muscle cells, leading to vasodilation.
Effects: Decreases blood pressure (primarily acts on vessels, less on the heart).
Uses: Hypertension (HTN), angina.
Adverse Effects:
Flushing, dizziness, peripheral edema, headache.
Important: Avoid grapefruit juice.Hint: Medications ending in -dipine (e.g., Nifedipine) Dilates vessels, Decreasing pressure.
Diuretics
Loop Diuretics: Furosemide
MOA: Blocks sodium and chloride reabsorption in the loop of Henle, causing strong diuresis.
Uses: Congestive Heart Failure (CHF), pulmonary edema, resistant hypertension (HTN).
Adverse Effects:
⚠️ Black Box Warning: Profound diuresis can lead to electrolyte loss.
Common: Hypokalemia, ototoxicity, dehydration, increased uric acid and glucose.Interactions: Increases digoxin toxicity if potassium levels are low.
Potassium-Sparing Diuretics: Spironolactone
MOA: Blocks aldosterone, leading to potassium retention and sodium excretion.
Uses: Hypertension (HTN), heart failure (HF), edema.
Adverse Effects:
Hyperkalemia, gynecomastia, menstrual irregularities.
⚠️ Important: Due to hormone-like effects, wear gloves when handling crushed tablets.Avoid: Other potassium-increasing medications (e.g., ACE inhibitors, ARBs).
Antianginal Medications: Nitroglycerin
MOA: Primarily vasodilates veins, decreasing preload and myocardial oxygen demand. At higher doses, it also dilates arteries, reducing afterload.
Uses: Angina (short-acting for acute chest pain, long-acting for prevention).
Adverse Effects:
Expected: Headache, dizziness, hypotension.
Other: Reflex tachycardia.Avoid: Erectile dysfunction (ED) drugs (PDE5 inhibitors) due to risk of severe hypotension.
Routes: Sublingual, transdermal patch, intravenous (IV) – titrate based on blood pressure and chest pain.
Inotropic Agents
PDE Inhibitors: Milrinone
MOA: Inhibits phosphodiesterase (PDE), increasing cyclic AMP (cAMP) and intracellular calcium, leading to stronger myocardial contraction. Also causes vasodilation, decreasing preload and afterload.
Uses: Acute decompensated heart failure (short-term, ICU only).
Adverse Effects:
Severe arrhythmias, hypotension, chest pain.
⚠️ Important: Do not mix with Furosemide (Lasix) IV due to precipitate formation.
Dopamine
Low Dose: Acts on dopamine receptors, dilating renal arteries and increasing kidney perfusion.
High Dose: Stimulates beta and alpha receptors, increasing heart rate, contractility, and blood pressure.
Uses: Shock (cardiogenic or hypovolemic).
Adverse Effects:
Dysrhythmias, hypertension (HTN).
⚠️ Black Box Warning: Extravasation can lead to tissue necrosis.
Antidote for infiltration: Phentolamine subcutaneous (SQ).
Lipid-Lowering Agents: Atorvastatin (Lipitor)
MOA: Inhibits HMG-CoA reductase, reducing cholesterol synthesis.
Effects: Decreases LDL (low-density lipoprotein) and triglycerides (TGs), increases HDL (high-density lipoprotein), reduces inflammation and plaque formation.
Uses: Hyperlipidemia, post-myocardial infarction (MI), cardiovascular (CV) risk prevention.
Adverse Effects:
⚠️ Rare but serious: Rhabdomyolysis, hepatotoxicity, memory issues.
Common: Gastrointestinal (GI) upset, headache.Avoid: Grapefruit juice, CYP3A4 inhibitors.
Labs to Monitor: Liver Function Tests (LFTs), Creatine Kinase (CK) for muscle breakdown.
Anticoagulants: Heparin
MOA: Activates antithrombin, which then inhibits thrombin and Factor Xa, preventing fibrin clot growth.
Uses: Prevention and treatment of Deep Vein Thrombosis (DVT), Pulmonary Embolism (PE), and stroke; safe in pregnancy; used during surgery or dialysis.
Route: Intravenous (IV) or subcutaneous (SQ) – NEVER intramuscular (IM).
Monitoring:
Activated Partial Thromboplastin Time (aPTT) – goal: 1.5–2 times normal.Antidote: Protamine sulfate.
Adverse Effects:
⚠️ Bleeding, Heparin-Induced Thrombocytopenia (HIT), spinal hematoma.Dietary Considerations: No major food concerns.
Hint: Fast-acting with a short half-life. Requires close monitoring!
Anticoagulants: Warfarin (Coumadin)
MOA: Vitamin K antagonist, reducing the production of clotting factors II, VII, IX, and X.
Uses: Long-term prevention of clots (e.g., atrial fibrillation, prosthetic heart valves, DVT, PE).
Monitoring:
Prothrombin Time/International Normalized Ratio (PT/INR) – goal: INR 2–3.Antidote: Vitamin K.
Adverse Effects:
⚠️ Bleeding, fetal harm (Pregnancy Category X).Dietary Considerations: Maintain consistent intake of vitamin K foods (e.g., green leafy vegetables).
Interactions: Numerous drug interactions, including antibiotics, acetaminophen, birth control pills, and herbal supplements.
Hint: Slow onset of action (takes days), long half-life.
Direct Oral Anticoagulants (DOACs): Apixaban (Eliquis)
MOA: Directly inhibits Factor Xa, thereby blocking thrombin production.
Uses: Atrial fibrillation (A-fib), Deep Vein Thrombosis (DVT)/Pulmonary Embolism (PE) prevention after surgery.
Advantages:
No routine lab monitoring required.
Lower risk of bleeding compared to warfarin.
Fast onset of action.Risks:
Bleeding, spinal hematoma.Patient Education:
Avoid grapefruit juice.
Take at consistent times.
Do NOT stop abruptly.
No specific antidote (activated charcoal may be given if recently ingested).Hint: Medications ending in -xaban directly block Factor Xa.
Antiplatelet Agents: Clopidogrel (Plavix)
MOA: Blocks ADP receptors on platelets, preventing platelet aggregation.
Uses: Prevents stent thrombosis, myocardial infarction (MI), and stroke.
Adverse Effects:
Bleeding, abdominal pain, rash, Thrombotic Thrombocytopenic Purpura (TTP) (rare but serious).
⚠️ Important: Takes up to 10 days to reverse effects; discontinue 5-7 days before surgery.Interactions: Proton Pump Inhibitors (PPIs), Selective Serotonin Reuptake Inhibitors (SSRIs), statins, other anticoagulants.
Antidote: None.
Hint: Clopidogrel clops (blocks) platelets, preventing clots.
Thrombolytic Agents: Alteplase (tPA)
MOA: Converts plasminogen to plasmin, which then dissolves fibrin clots.
Uses: Emergency clot breakdown (e.g., myocardial infarction, ischemic stroke, pulmonary embolism, central line clots).
Adverse Effects:
⚠️ Major bleeding, especially intracranial hemorrhage.Contraindications: Recent surgery, trauma, active bleeding disorders.
Antidote:
Aminocaproic acid or tranexamic acid.
For major bleeding, plasma/blood products may be administered.Nursing Considerations: Frequent neurological checks, strict bleeding precautions.
Hint: Thrombolytic agents lyse (break down) existing clots, unlike anticoagulants which prevent clot formation.
Erythropoiesis-Stimulating Agents: Epoetin Alfa
MOA: Stimulates bone marrow to produce red blood cells (RBCs), mimicking natural erythropoietin.
Uses: Anemia associated with Chronic Kidney Disease (CKD) or chemotherapy.
Adverse Effects:
⚠️ Hypertension (HTN), stroke, myocardial infarction (MI), seizures.
⚠️ Black Box Warning: Do NOT administer if hemoglobin (Hgb) is >11 g/dL due to increased clot risk.Nursing Considerations: Monitor blood pressure (BP), hemoglobin (Hgb), and hematocrit (Hct).
Hint: EPOetin alfa stimulates ErythroPOiesis, providing an RBC boost.
Iron Supplements: Ferrous Sulfate
Uses: Iron-deficiency anemia.
Adverse Effects:
Gastrointestinal (GI) upset, constipation, dark stools, teeth staining (with liquid formulations).Patient Education:
Take with Vitamin C to enhance absorption.
Avoid dairy products and antacids (decrease absorption).
Use a straw with liquid forms to prevent teeth staining.
Increase fiber intake to manage constipation.Antidote (for overdose): Deferoxamine.
Colony-Stimulating Factors: Filgrastim (Neupogen)
MOA: Stimulates the production of white blood cells (WBCs), particularly neutrophils.
Uses: Prevents infection in chemotherapy patients (due to neutropenia).
Adverse Effects:
Bone pain, splenomegaly, increased WBC count (leukocytosis).Nursing Considerations: Monitor Complete Blood Count (CBC), especially neutrophil count. Educate patients on self-injection techniques.
Hint: Fil-GRASTIM Grows Granulocytes (a type of WBC).
Insulin Types
Rapid-Acting Insulin: Aspart (Novolog)
Onset: 15 minutes | Peak: 1 hour | Duration: 3–6 hours.
Uses: Administer with meals; food must be present.
Route: Subcutaneous (SQ) only.
Black Box Warning: None.
Antidote for Hypoglycemia: Dextrose or Glucagon.
Short-Acting Insulin: Regular (Humulin R)
Subcutaneous (SQ) Onset: 30–60 minutes | Peak: 1–5 hours | Duration: 6–10 hours.
Intravenous (IV) Onset: 5–15 minutes | Peak: 15–30 minutes.
Important: Only insulin that can be administered intravenously (IV).
Black Box Warning: None.
Antidote for Hypoglycemia: Dextrose or Glucagon.
Long-Acting Insulin: Glargine (Lantus)
Onset: 1–2 hours | Peak: None | Duration: 24 hours.
Important: Do NOT mix with other insulins.
Black Box Warning: None.
Antidote for Hypoglycemia: Dextrose or Glucagon.
Oral Antidiabetic Medications
Metformin (Glucophage)
MOA: Decreases hepatic glucose production and increases insulin sensitivity.
Adverse Effects: Gastrointestinal (GI) upset, lactic acidosis (potentially fatal), Vitamin B12 deficiency.
⚠️ Important: Hold 24–48 hours before contrast media administration, and restart 48 hours after.
Black Box Warning: ⚠️ Lactic acidosis.
Antidote: Supportive care; dialysis may be required.
Sulfonylureas: Glyburide, Glipizide
MOA: Stimulates pancreatic beta cells to release insulin.
Adverse Effects: Hypoglycemia, weight gain, disulfiram-like reaction with alcohol consumption.
Black Box Warning: None.
Antidote for Hypoglycemia: Glucose.
Hypoglycemia Management
If Blood Glucose (BG) < 70 mg/dL: Administer 15g of simple carbohydrates (e.g., juice, glucose tablets). Recheck BG in 15 minutes; repeat if necessary. Once stable, provide a carbohydrate and protein snack.
For unconscious patients: Administer Glucagon intramuscular (IM) or intravenous (IV) Dextrose.
Antidepressants
SSRIs: Fluoxetine, Sertraline, Escitalopram
MOA: Selectively blocks serotonin reuptake.
Side Effects: Insomnia, sexual dysfunction, gastrointestinal (GI) upset, weight changes.
Black Box Warning: ⚠️ Increased suicide risk (especially in individuals under 25 years old).
Antidote: Supportive care; activated charcoal may be used for early ingestion.
Serotonin Syndrome
Cause: Excessive serotonin levels (e.g., concurrent use of SSRIs with MAOIs or St. John’s Wort).
Signs & Symptoms (HARMED mnemonic):
Hyperthermia, Agitation, Reflexes (hyperreflexia/clonus), Myoclonus, Encephalopathy, Diaphoresis.Treatment: Discontinue causative medication, benzodiazepines for agitation, cyproheptadine.
TCAs: Amitriptyline
MOA: Blocks the reuptake of serotonin and norepinephrine.
Risks:
Cardiac toxicity (e.g., fatal arrhythmias).
Anticholinergic effects: dry mouth, blurred vision, constipation.Black Box Warning: ⚠️ Increased suicide risk.
Antidote: Activated charcoal; sodium bicarbonate for cardiac effects.
Extrapyramidal Symptoms (EPS)
Associated Drugs: First-generation antipsychotics (e.g., Haloperidol).
Symptoms:
Dystonia (muscle spasms), Akathisia (restlessness), Parkinsonism (tremor, rigidity, bradykinesia), Tardive Dyskinesia (involuntary movements, e.g., lip smacking).Treatment: Benztropine; consider switching antipsychotic medication.
Dietary Management & Key Considerations
Diabetes Diet Principles
Emphasize: Complex carbohydrates, high fiber, low fat.
Limit: Refined sugars and starches.
Protein: 15–20% of total intake.
Recommendations: Limit alcohol, maintain consistent meal times.
Coronary Artery Disease (CAD) Diet
Dietary Approach: DASH diet recommended.
Limit: Saturated and trans fats.
Cholesterol: Aim for <200 mg/day.
Increase: Omega-3 fatty acids, fiber.
Reduce: Red meat intake.
Sodium: <3g/day for moderate heart failure, <2g/day for severe heart failure.
Malnutrition Indicators & Management
Marasmus: Characterized by severe muscle wasting.
Kwashiorkor: Characterized by edema and fatty liver.
Common Causes: Aging, chronic illness, trauma.
Nutrient Replacement: Vitamins C, E, zinc, selenium, copper.
Obesity Management Strategies
Obesity Definition: Body Mass Index (BMI) ≥ 30 kg/m².
Waist-Hip Ratio: Men >0.95, Women >0.8 (indicators of central obesity).
Caloric Reduction: Decrease 500–750 kcal/day for weight loss.
FDA-Approved Medications: Consider if BMI ≥30 (without comorbidities) or ≥27 with comorbidities.
Bariatric Surgery: Consider if BMI >40 or >35 with comorbidities.
Key Drug-Food Interactions
Statins: Avoid grapefruit juice.
Warfarin: Maintain consistent Vitamin K intake.
Iron Supplements: Enhance absorption with Vitamin C; avoid dairy and antacids.
MAOIs: Avoid tyramine-rich foods (e.g., aged cheeses, cured meats).