Pharmacology Overview for NCLEX

Aug 28, 2025

Overview

This lecture series provides a high-yield, system-by-system overview of pharmacology essentials for nursing students preparing for the NCLEX, focusing on mechanisms, key drugs, major side effects, and critical nursing considerations.

Foundations of Pharmacology

  • Pharmacokinetics is the process of drug absorption, distribution, metabolism (mainly liver, via cytochrome P450), and excretion (mainly kidneys).
  • Pharmacodynamics describes how drugs produce their effects, mainly through receptor activation (agonists) or blocking (antagonists).
  • Therapeutic index defines the safety margin of a drug; narrow index drugs require close monitoring.
  • Half-life determines how often a drug is dosed and duration of action.
  • Bioavailability is the proportion of a drug reaching circulation; oral drugs often have less due to first pass effect.

Autonomic Nervous System Medications

  • Adrenergic agonists stimulate fight-or-flight (↑HR, BP); examples: epinephrine, albuterol, dopamine.
  • Adrenergic antagonists (blockers) lower HR/BP; alpha blockers (end in -zosin) and beta blockers (end in -lol).
  • Cholinergic agonists stimulate rest-and-digest (↑secretions, ↓HR); monitor for cholinergic crisis (SLUDGE).
  • Anticholinergics block parasympathetic activity, causing dry mouth, urinary retention, constipation, blurred vision.

Cardiovascular Medications

  • ACE inhibitors (-pril) and ARBs (-sartan) lower BP via the RAAS; ACEI may cause cough, angioedema, hyperkalemia.
  • Beta blockers (-lol) slow HR, lower BP; must check vitals before giving, avoid abrupt stop, mask hypoglycemia.
  • Calcium channel blockers (e.g. amlodipine, verapamil) lower BP, some also slow HR; avoid grapefruit juice.
  • Diuretics include loop (furosemide), thiazide, and potassium-sparing (spironolactone); monitor electrolytes, give in morning.
  • Vasodilators (nitroglycerin, hydralazine) lower BP rapidly; key side effects: hypotension, reflex tachycardia.
  • Antiarrhythmics (amiodarone, lidocaine, adenosine) correct arrhythmias; monitor for toxicity (lungs, liver, thyroid for amiodarone).

Respiratory Medications

  • SABA (albuterol): rescue inhaler for acute asthma; side effects include tachycardia, tremors.
  • LABA (salmeterol): maintenance, must combine with inhaled steroids for asthma.
  • Anticholinergic inhalers (ipratropium, tiotropium): maintenance for COPD/asthma; not for rescue.
  • Corticosteroids (inhaled and systemic): control inflammation; rinse mouth after inhaled use.
  • Leukotriene modifiers (montelukast): prevention, not rescue.
  • Mucolytics (acetylcysteine) thin secretions; is also antidote for acetaminophen overdose.
  • Antitussives (dextromethorphan, codeine) suppress cough; avoid in productive cough.

Endocrine and Metabolic Medications

  • Levothyroxine: for hypothyroidism; take on empty stomach, lifelong therapy, monitor TSH.
  • Methimazole/PTU: for hyperthyroidism; monitor WBC and liver.
  • Insulin (types: rapid, short, intermediate, long-acting): match meals and peaks, monitor for hypoglycemia.
  • Metformin: first-line for type 2 DM; hold for contrast, monitor kidneys.
  • Sulfonylureas: risk of hypoglycemia, avoid alcohol.
  • Desmopressin (DDAVP): for diabetes insipidus, monitor sodium for water intoxication.
  • Bisphosphonates (alendronate): take upright, empty stomach, for osteoporosis.

GI Medications

  • PPIs (-prazole): potent acid reducers, risk for osteoporosis and C. diff.
  • H2 blockers (famotidine): milder acid reduction, can cause confusion in elderly.
  • Antacids: fast relief, space from other meds; Mg causes diarrhea, Al causes constipation.
  • Laxatives: bulk-forming safest, stimulants fastest but risk dependence, osmotics can cause dehydration, stool softeners for prevention.
  • Antidiarrheals: not for infections; loperamide slows gut, bismuth-subsalicylate contains aspirin.
  • Antiemetics: dopamine/serotonin antagonists risk extrapyramidal symptoms, QT prolongation; antihistamines cause sedation.

Anti-Infectives

  • Penicillins (-cillin): cell wall killers, watch for allergy and resistance, cross-react with cephalosporins.
  • Cephalosporins (cef-): similar to penicillins, avoid alcohol, monitor kidneys/bleeding.
  • Macrolides (-thromycin): risk QT prolongation, hepatotoxicity.
  • Fluoroquinolones (-floxacin): tendon rupture, photosensitivity, avoid dairy/antacids.
  • Tetracyclines (-cycline): avoid in kids/pregnancy, photosensitivity, no dairy/antacids.
  • Aminoglycosides (-mycin): nephro/ototoxicity, monitor levels.
  • Sulfonamides (sulfa-): allergy, kidney stones, photosensitivity, Stevens-Johnson syndrome.

Emergency/Critical Care Medications

  • Epinephrine: cardiac arrest/anaphylaxis, increases HR/BP; given IV or IM.
  • Atropine: treats bradycardia, dries secretions.
  • Vasopressors (norepinephrine, dopamine, dobutamine): for shock, monitor perfusion, give via central line.
  • Magnesium sulfate: for asthma/preeclampsia; monitor for toxicity (loss of reflexes, respiratory depression).

Pain and Sedation

  • Opioids (morphine, fentanyl, hydromorphone): risk respiratory depression, constipation, overdose reversed by naloxone.
  • NSAIDs (ibuprofen, ketorolac, aspirin): GI bleeding, renal risk, avoid in pregnancy.
  • Acetaminophen: liver toxicity, max 4g/day; avoid alcohol.
  • Adjuvants: anticonvulsants (gabapentin), antidepressants (amitriptyline), muscle relaxants.
  • Anesthetics: local (lidocaine), general (propofol, ketamine); monitor for respiratory and cardiac complications.

Psychotropic Medications

  • SSRIs/SNRIs: first-line for depression/anxiety, risk serotonin syndrome.
  • TCAs/MAOIs: older, more side effects/food interactions.
  • Antipsychotics: typical (EPS, NMS risk), atypical (weight gain, diabetes).
  • Lithium: narrow therapeutic range; monitor levels, maintain sodium/hydration.
  • Valproic acid: liver/pancreas/platelet monitoring.

Reproductive/Genitourinary Medications

  • Oral contraceptives: clot risk (avoid in certain populations), backup needed for missed doses.
  • Progesterone-only pills: strict timing.
  • Emergency contraception: use ASAP, not abortion pills.
  • ED drugs (-afil): never combine with nitrates; risk hypotension and priapism.
  • BPH meds (tamsulosin, finasteride): may cause hypotension, sexual side effects, handle 5-ARIs safely in pregnancy.

Key Terms & Definitions

  • Pharmacokinetics — how the body processes a drug (ADME: absorption, distribution, metabolism, excretion).
  • Pharmacodynamics — the effect a drug has on the body, including mechanism of action.
  • Therapeutic Index — range between effective and toxic doses.
  • First Pass Effect — metabolism in the liver reduces oral drug bioavailability.
  • Agonist/Antagonist — drugs that activate or block receptors.
  • Half-life — time for drug level to decrease by half.
  • Bioavailability — portion of drug that enters systemic circulation.
  • SLUDGE — mnemonic for cholinergic toxicity (Salivation, Lacrimation, Urination, Diarrhea, GI upset, Emesis).

Action Items / Next Steps

  • Review detailed lecture notes and practice questions on the course website.
  • Memorize major drug classes, mechanisms, side effects, and nursing implications using provided mnemonics.
  • Practice NCLEX-style questions focusing on high-yield drug safety and patient teaching.
  • Continue to monitor for updates and further lectures in this series.

Full transcript