Start Here: The Game Plan
How to use this guide, what is actually being tested, and a 3-day study schedule that gets you to mastery.
How To Use This Guide
- Read the concept card first — each card covers one learning objective with the “why” behind the drug or fluid.
- Flip every flip-card — they are your high-yield memory hooks (drug → mechanism / safety point).
- Tap every scenario — clinical scenarios test the same concepts with different words, exactly like the exam will.
- Answer the quick-checks as you go for instant feedback.
- Finish with the Mastery Quiz — aim for 90%+ before you call it done.
What Is Being Tested (Know The Shape Of The Exam)
This exam is overwhelmingly about pharmacology and parenteral therapies — the NCLEX category “Physiological Integrity – Pharmacological and Parenteral Therapies” is by far the largest slice. Expect mostly multiple-choice with a few select-all-that-apply, fill-in-the-blank (med math), and matching questions.
- Think APPLY and ANALYZE, not recall. You will be given a client situation and asked to choose the best action, question an order, or judge whether teaching worked.
- Nursing process = mostly PLAN and EVALUATE. Questions skew toward “what should the nurse do/plan” and “which statement shows the client understood.”
- Safety is the theme. Most questions reduce to: Which choice prevents harm? (never push potassium, never mix sildenafil with nitrates, hold teratogenic drugs in pregnancy, watch for fluid overload, question orders that could injure.)
High-Yield: Roughly two-thirds of the exam is GI/nutrition/reproductive pharmacology, one-quarter is IV fluids & electrolytes, and a small fixed block is dosage calculation. Prioritize your time in that order — but master all of it, because med math is free points.
The 3-Day Game Plan
Day 1 — Fluids & Electrolytes + Med Math (the foundations)
- Work through the IV Fluids & Electrolytes tab. Memorize the tonicity table cold — it unlocks ~10 objectives at once.
- Learn the hyperkalemia treatment ladder and the safe IV potassium rules.
- Do the Med Math tab — write out all 5 formulas and drill them until they are automatic (they are guaranteed points).
Day 2 — GI, Nutrition & Bowel
- Master the acid-suppression drug comparison table (antacid vs H2 blocker vs PPI vs sucralfate vs misoprostol vs bismuth).
- Nail TPN and enteral feeding safety, then the constipation ladder.
- Finish with the “one-off” drugs: vitamin A, folic acid, sulfasalazine, ondansetron, methylnaltrexone, IBD.
Day 3 — Reproductive, OB & Final Review
- Learn the estrogen/progestin risk & contraindication rules (DVT/PE/stroke, smoking, migraines with aura).
- Memorize the tocolytic vs uterotonic split and the magnesium sulfate toxicity picture + antidote.
- Take the Mastery Quiz. Re-flip every card you missed. Retake until 90%+.
Mastery Checklist
Check each objective off as you can explain it out loud from memory. Your progress is saved on this device.
0 / 0 mastered
- IV fluid tonicity — name iso/hypo/hypertonic examples, their fluid shifts, uses, and risks
- Crystalloids vs colloids — which stay in the vessel, when each is used
- Fluid overload — crackles, dyspnea, frothy sputum; lung sounds before/after boluses
- Acid–base — metabolic acidosis (Kussmaul) vs bicarbonate overcorrection (alkalosis)
- Hyperkalemia — insulin+dextrose, Kayexalate, calcium gluconate, dialysis
- Hyponatremia — 3% saline, correct slowly, watch for CPM
- IV potassium safety — never push, monitor site, check renal function
- Low-sodium diet — which foods to choose vs avoid
- TPN — central line, 30-min warm-up, hyperglycemia, q24h tubing, air embolism
- Enteral feedings — dehydration, aspiration, intolerance signs
- Acid-suppression drugs — antacid, H2 blocker, PPI, sucralfate, misoprostol, bismuth
- PPI long-term risks — fractures, B12 deficiency
- Constipation ladder — psyllium/bulk-forming, PEG, docusate, stimulants
- Ondansetron, methylnaltrexone, sulfasalazine, IBD, vitamin A, folic acid
- Contraception — interactions, contraindications, emergency contraception timing
- Estrogen / estradiol — DVT/PE/stroke risk, avoid smoking & grapefruit, contraindications
- Progestins — norethindrone & medroxyprogesterone key points
- Testosterone — patch schedule, therapeutic vs side effects
- HRT — risks, benefits, individualized decision
- Finasteride / 5-alpha reductase inhibitors — DHT, teratogenic, no blood donation
- Sildenafil — never with nitrates
- Oxytocin — postpartum hemorrhage prevention, uterine rupture risk
- Magnesium sulfate — tocolysis, toxicity signs, calcium gluconate antidote
- Tocolytics — terbutaline, nifedipine, indomethacin, mag vs oxytocin/misoprostol
- Med math — all 5 formulas, can solve any drip/rate/dose problem
IV Fluids & Electrolytes
Tonicity, crystalloids vs colloids, fluid overload, acid–base, and the potassium/sodium imbalances — the highest-yield non-drug content on the exam.
IV Fluid Tonicity (Iso · Hypo · Hyper)
Tonicity = the solute concentration of the fluid compared to blood plasma. It decides which way water moves between the bloodstream and the cells.
| Type | Examples | Fluid Shift | Use For | Watch For |
|---|---|---|---|---|
| Isotonic | 0.9% NaCl (Normal Saline), Lactated Ringer’s (LR) | No net shift — stays in vascular space | Fluid loss (vomiting/diarrhea), dehydration, mild blood loss, hypovolemia | Fluid overload if given too fast / too much |
| Hypotonic | 0.45% NaCl (“half-normal”), D5W (acts hypotonic in body) | Water moves INTO cells (hydrates cells, shrinks vessels) | Hypernatremia, cellular dehydration | Cellular swelling — NEVER for cerebral edema/ICP |
| Hypertonic | 3% NaCl, D5NS, D5LR, D10W | Water moves OUT of cells into vessels (expands volume) | Cerebral edema / increased ICP, severe hyponatremia | Fluid overload, hypernatremia — give via central line |
Key Concept: Hypotonic = water into the cell. Hypertonic = water out of the cell. The cell “follows the solutes.” D5W is isotonic in the bag but acts hypotonic in the body because the dextrose is metabolized, leaving free water.
0.9% NaCl & LR
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ISOTONIC
No fluid shift. Replace fluid loss from vomiting, diarrhea, dehydration.
0.45% NaCl
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HYPOTONIC
Water into cells. For hypernatremia / cellular dehydration.
3% NaCl, D5NS
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HYPERTONIC
Water out of cells. For cerebral edema & severe hyponatremia.
D5W
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Isotonic in bag → HYPOTONIC in body
Dextrose is metabolized, leaving free water.
Crystalloids vs Colloids
- Crystalloids = water + electrolytes (and sometimes glucose). Small molecules that mimic extracellular fluid and move freely between the vascular and interstitial compartments. (NS, LR, D5W.)
- Colloids = large molecules (proteins or starches) that stay in the vascular space and pull fluid in by oncotic pressure. (Albumin, dextran, hetastarch.)
Crystalloid
use for?
Hydration, resuscitation, electrolyte correction
NS, LR — move freely between compartments.
Colloid
use for?
Hypovolemic shock, blood loss, hypoalbuminemia
Albumin, dextran — stay in vessels, raise oncotic pressure.
Clinical Pearl
Cirrhosis with ascites = hypoalbuminemia → a colloid (albumin) pulls fluid back into the vessels and reduces ascites. Acute blood loss from trauma = colloid restores circulating volume fast.
Fluid Overload — The Colloid Caution
Colloids (like dextran 40) and rapid isotonic boluses push too much fluid into the vasculature. The result is fluid overload → pulmonary edema.
- Signs: crackles in lung bases, dyspnea, tachycardia, cough, frothy/pink sputum, peripheral edema.
- Priority assessment before & after any fluid bolus: auscultate lung sounds to catch early crackles/wheezing.
Critical Safety
Dextran (a colloid) is a volume expander — its #1 complication is fluid overload/pulmonary edema. If a client on dextran develops rapid heart rate + difficulty breathing + frothy sputum, think pulmonary edema, not allergy.
Hypertonic & Hypotonic In Action
- Brain swelling / increased ICP → give hypertonic 3% saline to pull water out of brain cells and lower ICP. Priority: frequent neuro checks + serum sodium; central line.
- Severe hyponatremia → hypertonic 3% saline raises sodium by drawing water out of cells.
- Hypernatremia (Na > 145) → give hypotonic 0.45% saline to shift water into cells and dilute the sodium.
Clinical Scenario
A client is admitted confused with a serum sodium of 114 mEq/L (normal 135–145) and started on a 3% NaCl infusion. What does the nurse anticipate?
Tap to reveal the answerAnswer: Serial sodium draws (about every 2 hours) and gradual correction. Sodium must rise slowly — correcting hyponatremia too fast causes central pontine myelinolysis (osmotic demyelination syndrome). Expect improvement over days, not hours, and watch for fluid overload (hypertonic fluids pull water into the vessels).
Acid–Base Basics
| Imbalance | Hallmark Signs | Note |
|---|---|---|
| Metabolic acidosis | Weakness, confusion, Kussmaul respirations (rapid & deep to blow off CO2) | Treat cause; sodium bicarbonate may be given |
| Metabolic alkalosis | Slowed respirations (compensatory CO2 retention), irritability, muscle twitching, confusion | Classic cause here = bicarbonate overcorrection |
Clinical Pearl
Giving sodium bicarbonate to fix acidosis can overshoot into alkalosis. If a client on bicarbonate develops a slowing respiratory rate + irritability + muscle twitching, you overcorrected → metabolic alkalosis. Slow breathing is the tell (the body retains CO2 to re-acidify).
Quick Check
A client is weak, confused, and breathing rapidly and deeply. Which imbalance should you suspect?
Rapid, deep (Kussmaul) respirations blow off CO2 to compensate — the classic picture of metabolic acidosis.
Hyperkalemia — The Treatment Ladder
Normal potassium = 3.5–5.0 mEq/L. Elevated potassium is dangerous because it destabilizes cardiac conduction (peaked T waves → wide QRS → arrest).
| Intervention | What It Does | When |
|---|---|---|
| IV insulin + IV dextrose | Shifts potassium INTO cells (dextrose prevents hypoglycemia) | Rapid, first-line shift |
| Calcium gluconate | Stabilizes the cardiac membrane (does NOT lower K) | ECG changes / cardiac protection |
| Sodium polystyrene sulfonate (Kayexalate) | Removes potassium via the GI tract | Slower elimination |
| Hemodialysis | Physically removes potassium | Renal failure / severe (K > 7) |
High-Yield: For a client with hyperkalemia, question any order that adds potassium or sodium — including 0.9% normal saline (sodium shifts potassium out of cells into the blood, worsening the problem) and any potassium-containing fluid.
Safe IV Potassium Replacement (KCl)
- NEVER give potassium as an IV push — causes fatal arrhythmias / cardiac arrest. Always dilute and infuse slowly on a pump.
- Check kidney function first (BUN/creatinine) — impaired kidneys can’t excrete potassium → hyperkalemia.
- Monitor the IV site for burning and infiltration — KCl is highly irritating and can destroy tissue.
- Cardiac monitoring for clients at risk (chronic kidney disease, abnormal ECG conduction).
Critical Safety
Potassium chloride + IV push = cardiac arrest. This is one of the single most-tested medication-safety rules in nursing. Also question KCl for anyone in acute renal failure.
Low-Sodium Diet — Teaching
- CHOOSE: fresh fruits & vegetables, broiled/grilled unprocessed meats, plain baked potato, oatmeal, apple slices with peanut butter.
- AVOID: canned soup, deli & ham, sausage, pickles/pickled vegetables, frozen dinners, cheese-based dishes.
Quick Check
A client with heart failure is on a sodium-restricted diet. Which family-brought item should the nurse approve?
Fresh fruit and unsalted peanut butter are naturally low in sodium; the others are processed/high-sodium.
GI, Nutrition & Bowel
Parenteral & enteral nutrition, the acid-suppression drug family, laxatives, and the GI one-offs. This is the largest block of the exam.
TPN (Total Parenteral Nutrition)
- Route: IV via a central line only (high osmolarity) — never peripheral, never a PEG/feeding tube.
- Prep: remove from the refrigerator ~30 minutes before infusing (cold solutions cause vasoconstriction and discomfort).
- Most common complication: hyperglycemia (TPN is high-dextrose) → monitor blood glucose.
- Infection control: change the solution bag and tubing every 24 hours.
- Never stop abruptly — taper to avoid rebound hypoglycemia.
- Air embolism (sudden lightheadedness + SOB during infusion): clamp the catheter and place in Trendelenburg / left lateral position.
Clinical Scenario
During a TPN infusion via central line, the client suddenly reports lightheadedness and shortness of breath. What is the nurse’s first action?
Tap to reveal the answerAnswer: Suspect an air embolism — clamp the catheter and place the client in Trendelenburg (with a left-side tilt). This stops more air entering and traps air in the right atrium. Do NOT flush the line.
TPN route
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Central line only
High osmolarity — never peripheral or PEG.
#1 TPN complication
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Hyperglycemia
High dextrose — monitor blood glucose.
Tubing change
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Every 24 hours
Prevents bacterial growth in the dextrose solution.
Enteral Feedings (Tube Feedings)
- Dehydration risk: watch for dry mucous membranes — enteral formulas don’t always supply enough fluid.
- Aspiration risk: a sudden increase in respiratory rate + labored breathing = suspect aspiration.
- Intolerance: abdominal distension + hypoactive bowel sounds = delayed gastric emptying / ileus → notify the provider. (A small gastric residual like 15 mL is normal.)
Acid-Suppression & Peptic Ulcer Drugs — Master Table
| Drug / Class | Mechanism | Key Point / Safety |
|---|---|---|
| Antacids | Neutralize existing stomach acid | Temporary relief only; don’t reduce production; space 1–2 hr from other meds; avoid milk |
| H2 receptor antagonists (famotidine, ranitidine) | Block histamine H2 receptors on parietal cells → less acid | Don’t take with antacids (impaired absorption); effectiveness = relief of heartburn |
| Proton pump inhibitors (omeprazole, pantoprazole) | Inhibit H+/K+-ATPase (proton pump) → strongest acid suppression | Ulcer/esophagus heals in ~4–8 weeks; long-term risks = fractures & B12 deficiency |
| Sucralfate | Forms a protective barrier over the ulcer (no acid change) | Empty stomach ~1 hr before meals; not with antacids |
| Misoprostol | Prostaglandin analog → ↑ mucus + bicarbonate, ↓ acid | Protects gastric mucosa; CONTRAINDICATED in pregnancy |
| Bismuth subsalicylate | Binds/absorbs toxins (antidiarrheal) | Harmless black stools; avoid if aspirin allergy |
High-Yield: Know exactly which drug does what. PPIs stop the pump (production). H2 blockers block the histamine signal. Antacids just neutralize what’s there. Sucralfate coats. Misoprostol protects with mucus. Bismuth absorbs toxins. Mixing these up is the #1 way to lose points.
Antacid
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Neutralizes existing acid
Temporary relief; not enough to heal an ulcer.
H2 blocker
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Blocks H2 receptors on parietal cells
Reduces acid; don’t combine with antacids.
PPI
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Blocks the proton pump (H+/K+-ATPase)
Most potent; healing ~4–8 weeks.
Sucralfate
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Protective barrier over the ulcer
Empty stomach, 1 hr before meals.
Misoprostol
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↑ mucus + bicarbonate, ↓ acid
Prostaglandin — NO in pregnancy.
Bismuth
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Binds/absorbs toxins
Black stools; avoid with aspirin allergy.
PPI Long-Term Risks & Healing Time
- Long-term risks: fractures / osteoporosis (reduced calcium absorption) and vitamin B12 deficiency (acid is needed to release B12). Possible C. difficile risk.
- Healing: a gastric ulcer or damaged esophagus typically takes 4–8 weeks to heal on a PPI, even though symptom relief comes sooner.
Clinical Pearl
When a client asks “how long until my ulcer heals?” the safe answer is weeks (4–8), not minutes or days. When they ask about long-term risks, the two that show up most are fractures and B12 deficiency.
H2 Blockers & Antacids — Teaching That “Sticks”
- Antacid teaching: they neutralize acid for quick, temporary relief; they do NOT heal ulcers (that needs a PPI/H2 blocker); do NOT take with milk; do NOT take with other meds (space 1–2 hours).
- H2 blocker teaching: don’t combine with antacids (impaired absorption); keep taking even when symptoms improve; don’t self-treat with herbal remedies without asking.
Quick Check
Which client statement about GERD teaching shows a need for FURTHER teaching?
Antacids interfere with H2-blocker absorption — they should be spaced apart, not taken together.
The Constipation Ladder
| Class | Example | How It Works | Note |
|---|---|---|---|
| Bulk-forming (first-line) | Psyllium mucilloid | Absorbs water → soft, bulky stool; promotes peristalsis | MUST take with full glass of water; takes 12–72 hr |
| Osmotic | Polyethylene glycol (PEG) | Pulls water into the bowel | Also a first-line choice; gentle |
| Stool softener | Docusate sodium | Draws water INTO the stool to soften it | Does NOT stimulate peristalsis |
| Stimulant | Bisacodyl, senna | Stimulates bowel muscle contraction | Not first-line; for acute/short-term |
High-Yield: Bulk-forming laxatives (psyllium) are the first-line treatment for constipation. Their effectiveness = soft, formed stools that pass without straining. A client who “expects immediate relief” or who plans to “limit fluids” needs more teaching — psyllium takes 12–72 hours and requires plenty of water.
Opioid-Induced Constipation & The Rest of the One-Offs
Methylnaltrexone
- Peripheral opioid antagonist — treats opioid-induced constipation in clients on long-term/high-dose opioids (e.g., morphine for cancer pain) who haven’t responded to usual laxatives.
Ondansetron (antiemetic)
- 5-HT3 antagonist. Give it BEFORE the nauseating agent (chemo, antibiotic, analgesic) — prevention beats treatment.
- Adverse effect: QT prolongation — question the order in clients with cardiac conduction abnormalities or a known hypersensitivity.
Sulfasalazine (ulcerative colitis / IBD)
- Metabolized by the liver — question in liver disease (hepatitis, liver failure).
- Can cause bone marrow suppression → leukopenia (low WBC) — hold and contact the provider for a low WBC.
Inflammatory Bowel Disease — acute exacerbation
- Immediate goal: reduce acute inflammation and symptoms (NOT cure — IBD is chronic).
- Priority action: rehydrate (IV fluids + electrolytes) and initiate bowel rest.
Vitamin A
- Fat-soluble; essential for night vision (sources: carrots, spinach — beta-carotene).
- Excess is teratogenic (fetal harm) and hepatotoxic (elevated ALT/AST) — question high doses in pregnancy or with abnormal liver enzymes.
Folic acid
- B vitamin for RBC production — prescribed for folate-deficiency (megaloblastic/macrocytic) anemia.
- Alcohol abuse impairs folate absorption → a classic cause of deficiency.
Methylnaltrexone
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Opioid-induced constipation
For high-dose/long-term opioid users.
Ondansetron
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Antiemetic — give BEFORE the trigger
Watch QT prolongation.
Sulfasalazine
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Liver-metabolized; risk of low WBC
Question in liver disease / leukopenia.
Vitamin A
tap to flip
Night vision; teratogenic & hepatotoxic in excess
Carrots/spinach = beta-carotene.
Folic acid
tap to flip
Treats macrocytic (folate-deficiency) anemia
Alcohol abuse → folate deficiency.
Reproductive & Hormones
Contraception, estrogen/progestin therapy, testosterone, HRT, and the urologic drugs. The theme is clot risk and teratogenicity.
Estrogen & Combined Hormones — The Clot-Risk Family
Estrogen (conjugated estrogen, estradiol, and combined oral contraceptives) increases clotting — the central fact behind almost every question in this block.
- Biggest risks: DVT, pulmonary embolism, stroke, MI (thromboembolic events).
- Contraindications: history of thromboembolism (DVT/PE/stroke), abnormal/undiagnosed uterine bleeding, estrogen-dependent cancer, migraines with aura (raises stroke risk).
- Caution with: smoking (esp. age >35), hypertension, hypothyroidism (estrogen raises thyroid-binding globulin).
- Lifestyle teaching: avoid smoking and grapefruit juice (both raise drug levels / clot risk).
Critical Safety
Sudden shortness of breath + chest pain or unilateral leg pain/swelling in a client on estrogen = possible PE/DVT → seek immediate care. Teach every client on estrogen to recognize these.
Estrogen #1 risk
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Thromboembolism
DVT, PE, stroke, MI.
Avoid with estrogen
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Smoking & grapefruit juice
Both raise clot risk / drug levels.
Estrogen contraindications
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DVT/PE/stroke, abnormal uterine bleeding, migraine with aura
Also estrogen-dependent cancer.
Contraception — Interactions & Contraindications
- Reduces effectiveness of oral contraceptives: enzyme-inducing anticonvulsants (phenytoin, carbamazepine), antibiotics (especially rifampin), and St. John’s wort.
- Contraindications / caution: smoking (especially >35), hypertension, history of DVT/stroke, migraines with aura.
Emergency contraception
- Most effective as soon as possible after unprotected sex. Levonorgestrel works within ~72 hours; ulipristal acetate up to 5 days.
- Most important question to ask first: “How long ago did you have unprotected sex?”
Clinical Pearl
For emergency contraception, the single most useful thing the nurse determines is time since intercourse — it decides which option (if any) still works. Enzyme inducers (anticonvulsants, rifampin, St. John’s wort) also blunt its effectiveness.
Progestins — Norethindrone & Medroxyprogesterone
| Drug | Key Points |
|---|---|
| Norethindrone (progestin-only pill) | Take at the same time daily (missed/irregular doses → contraceptive failure); side effects = acne and photosensitivity |
| Medroxyprogesterone (Depo-Provera injection) | Interacts with St. John’s wort; contraindicated with thromboembolic disease, pregnancy, breast cancer; caution with depression (can recur); adverse = DVT (watch unilateral leg pain/swelling) |
Testosterone
- Patch: apply daily (per most formulations) and rotate sites to maintain steady levels.
- Signs it’s WORKING: improved libido, energy, mood, muscle mass; hematocrit rising within normal limits.
- Side effects (NOT signs of effectiveness): acne, oily skin, fluid retention, hair loss.
Quick Check
Which finding indicates testosterone therapy is achieving its intended effect?
Improved libido/energy (and normalized hematocrit) = therapeutic response. Acne, oily skin, fluid retention, and hair loss are side effects.
Hormone Replacement Therapy (HRT) — Risks vs Benefits
- Risks (estrogen–progestin): MI, stroke, venous thromboembolism (DVT/PE), dementia (esp. women >65), and breast cancer; endometrial hyperplasia with unopposed estrogen.
- Benefits: relieves hot flashes/vasomotor symptoms, reduces fracture risk (protects bone), may reduce colorectal cancer.
- Counseling: the decision is individualized — weigh personal risks vs benefits with the provider. Avoid blanket “it’s always safe” or “it’s always dangerous” answers.
Clinical Pearl
The “best” answer when a client is unsure about HRT is always the balanced one: acknowledge both risks and benefits and make it an individualized, shared decision. Never tell her it’s risk-free, and never tell her the risks outweigh benefits for everyone.
Finasteride & 5-Alpha Reductase Inhibitors (BPH)
- Mechanism: inhibit 5-alpha reductase → block testosterone → DHT conversion → shrink the prostate (relieves BPH symptoms like nocturia). Takes months (unlike alpha-blockers, which relax smooth muscle fast).
- Side effects: sexual dysfunction (decreased libido, ED), dizziness, headache.
- TERATOGENIC: harms a male fetus. Do not donate blood; pregnant women should not handle crushed tablets; assess whether a partner could be pregnant.
Critical Safety
Finasteride is teratogenic. Two always-tested safety points: (1) no blood donation while taking it, and (2) assess whether the client’s partner could be pregnant (secondary exposure via semen/handling).
Finasteride MOA
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Blocks testosterone → DHT
Shrinks the prostate over months.
Finasteride safety
tap to flip
Teratogenic — no blood donation
Protect pregnant partners.
Sildenafil (Erectile Dysfunction)
- Mechanism: PDE5 inhibitor — relaxes vascular smooth muscle and increases blood flow.
- Absolute contraindication: nitrates (nitroglycerin, isosorbide) — the combination causes dangerous, life-threatening hypotension.
High-Yield: A client with angina who wants sildenafil — the answer is always nitrates are contraindicated. Any nitrate (nitroglycerin, isosorbide) + sildenafil = severe hypotension.
OB & Labor Medications
Oxytocin, magnesium sulfate, terbutaline, and the tocolytic family — the “speed up vs slow down the uterus” block.
Oxytocin (Pitocin)
- Uses: induce/augment labor and postpartum to contract the uterus and prevent hemorrhage (uterine atony).
- Adverse effects: uterine hyperstimulation (rapid, painful contractions), uterine rupture (risk rises with grand multiparity / many prior births), and water intoxication.
Clinical Pearl
Postpartum oxytocin’s primary goal is to contract the uterus and reduce bleeding. A history of five previous vaginal births (grand multiparity) is the red flag for uterine rupture during induction.
Magnesium Sulfate
- Uses: prevent/treat seizures in preeclampsia/eclampsia; tocolytic (delay preterm labor by relaxing uterine smooth muscle); off-label for severe asthma (bronchodilation).
- Toxicity (overdose) signs: loss of deep tendon reflexes, respiratory depression, bradycardia, hypotension, drowsiness, muscle weakness, flushing.
- Antidote: calcium gluconate.
Clinical Scenario
A client on IV magnesium sulfate becomes very drowsy, states “I can’t move my arms,” has absent deep tendon reflexes, a heart rate of 48, and respirations of 8/min. What is happening and what is the priority action?
Tap to reveal the answerAnswer: Magnesium toxicity (neuromuscular + respiratory depression). Priority: stop the infusion, notify the provider, and administer calcium gluconate as prescribed. Never increase the mag rate — that worsens toxicity.
Mag sulfate uses
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Preeclampsia seizures, tocolysis, asthma
Relaxes smooth muscle.
Mag toxicity
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Lost DTRs, resp depression, bradycardia
Drowsy, weak, hypotensive.
Mag antidote
tap to flip
Calcium gluconate
Give as prescribed, stop the infusion.
Terbutaline & The Tocolytics
- Terbutaline = beta-2 agonist tocolytic. Black box warning: prolonged use (>48–72 hours) risks fetal death. Side effects: tachycardia/palpitations; report shortness of breath (pulmonary edema).
- Tocolytics (slow the uterus down): terbutaline, nifedipine (calcium channel blocker), indomethacin (prostaglandin inhibitor), magnesium sulfate, ritodrine.
- NOT tocolytics (they stimulate/induce the uterus): oxytocin, misoprostol, methylergonovine, carboprost. Betamethasone is a corticosteroid for fetal lung maturity (neither a tocolytic nor a uterotonic).
| Class | Drugs | Effect on Uterus |
|---|---|---|
| Tocolytics (delay labor) | Terbutaline, nifedipine, indomethacin, magnesium sulfate, ritodrine | Relax / suppress contractions |
| Uterotonics (contract/induce) | Oxytocin, misoprostol, methylergonovine, carboprost | Stimulate contractions |
| Corticosteroid | Betamethasone | Matures fetal lungs (not a tocolytic) |
High-Yield: In a preterm-labor scenario, pick the drugs that relax the uterus (terbutaline, nifedipine, indomethacin, mag). The trap answers are always oxytocin, misoprostol, and methylergonovine — those contract the uterus.
Med Math — Dosage Calculations
Five formulas cover every calculation on the exam. These are guaranteed points — learn them cold.
The Five Formulas
| You Are Asked For | Formula |
|---|---|
| Infusion time (hours) | Time (hr) = Volume (mL) ÷ Rate (mL/hr) |
| Drip rate (gtt/min) | gtt/min = (Volume mL × Drop factor gtt/mL) ÷ Time (min) |
| IV pump rate (mL/hr) | mL/hr = Volume (mL) ÷ Time (hr) |
| Volume to give (mL) | mL = Dose ordered (mg) ÷ Concentration (mg/mL) |
| Drip rate from mL/hr | gtt/min = (mL/hr × Drop factor) ÷ 60 |
Golden rules: Convert minutes to hours (or hours to minutes) first. Always round as directed (whole number, or nearest tenth). The two “drop factor” formulas both end with “divide by time in minutes.”
Worked Examples
1 — Infusion time
750 mL at 75 mL/hr → 750 ÷ 75 = 10 hours
2 — Drip rate (gtt/min)
500 mL over 7 hr, drop factor 15 → (500 × 15) ÷ (7 × 60) = 7500 ÷ 420 ≈ 18 gtt/min
3 — IV pump rate (mL/hr)
100 mL over 30 min → 100 ÷ 0.5 hr = 200 mL/hr
4 — Volume to give (mL)
1.25 mg ordered, available 10 mg/mL → 1.25 ÷ 10 = 0.125 → 0.1 mL
5 — Drip rate from mL/hr
170 mL/hr, drop factor 10 → (170 × 10) ÷ 60 = 1700 ÷ 60 ≈ 28 gtt/min
Practice — Solve, Then Check
Quick Check — Med Math
Order: 960 mL NS at 80 mL/hr. How many hours will the infusion run?
960 ÷ 80 = 12 hours.
Order: 1,000 mL over 8 hours, drop factor 10 gtt/mL. What is the drip rate (round to whole number)?
(1000 × 10) ÷ (8 × 60) = 10000 ÷ 480 ≈ 20.8 → 21 gtt/min.
Order: 1.25 g in 250 mL to infuse over 90 minutes. What is the IV pump rate (round to whole number)?
250 mL ÷ 1.5 hr = 166.7 → 167 mL/hr.
Order: 2.5 mg IM; available 5 mg/mL. How many mL do you give?
2.5 ÷ 5 = 0.5 mL.
IV ordered at 220 mL/hr, drop factor 15 gtt/mL. What is the drip rate?
(220 × 15) ÷ 60 = 3300 ÷ 60 = 55 gtt/min.
Mastery Quiz
A comprehensive, concept-based self-assessment. Aim for 90%+ — if you can clear that, you are ready.
Full-Length Self-Assessment
Question 1 of 30
Which IV fluid is classified as hypertonic?
Correct! 3% saline is hypertonic — it pulls water out of cells into the vessels. 0.45% is hypotonic, 0.9% is isotonic, and D5W acts hypotonic in the body.
Question 2 of 30
A client arrives with nausea, vomiting, dry mucous membranes, and a serum sodium of 155 mEq/L. Which IV fluid should the nurse anticipate?
Correct! Sodium 155 is hypernatremia. A hypotonic solution (0.45% saline) shifts water into cells to dilute the excess sodium. 3% saline would worsen it.
Question 3 of 30
Which statement correctly distinguishes a crystalloid from a colloid?
Correct! Colloids (albumin, dextran) are large molecules that stay in the vessel and pull fluid in. Crystalloids (NS, LR) are small electrolytes that move freely between compartments.
Question 4 of 30
A client receiving dextran 40 develops tachycardia, dyspnea, a cough, and frothy sputum. What complication is the nurse most concerned about?
Correct! Dextran is a colloid volume expander; its key complication is fluid overload leading to pulmonary edema (tachycardia, dyspnea, frothy sputum).
Question 5 of 30
Before and after administering a 1-liter isotonic fluid bolus, which assessment is most important?
Correct! Lung sounds catch early crackles/wheezing from fluid overload — the top concern with a rapid isotonic bolus.
Question 6 of 30
A client has increased intracranial pressure from a brain injury. Which fluid does the nurse anticipate?
Correct! Hypertonic saline draws fluid out of brain cells into the vasculature, reducing cerebral edema and ICP. Hypotonic fluids would worsen swelling.
Question 7 of 30
A client is weak, confused, and breathing rapidly and deeply. Which acid–base imbalance should the nurse suspect?
Correct! Rapid, deep (Kussmaul) respirations are the body’s compensation to blow off CO2 — the hallmark of metabolic acidosis.
Question 8 of 30
A client receiving sodium bicarbonate develops a slowing respiratory rate, irritability, and muscle twitching. What has occurred?
Correct! Bicarbonate overcorrected the acidosis into alkalosis. Slowed respirations (CO2 retention) and irritability/twitching are classic alkalosis signs.
Question 9 of 30
A client has a potassium of 6.5 mEq/L. Which intervention does the nurse anticipate FIRST to shift potassium into the cells?
Correct! Insulin drives potassium into cells, and dextrose prevents the resulting hypoglycemia — the rapid first-line shift for hyperkalemia. Kayexalate works slower, via the gut.
Question 10 of 30
A client is hyperkalemic. Which IV fluid order should the nurse question?
Correct! Normal saline’s sodium can shift potassium out of cells into the blood, worsening hyperkalemia — so the nurse questions it. (Potassium-containing fluids would be even more clearly wrong.)
Question 11 of 30
A client’s sodium is 114 mEq/L and a 3% NaCl infusion is started. What does the nurse anticipate?
Correct! Hyponatremia must be corrected slowly (serial sodium draws, roughly every 2 hours) to avoid central pontine myelinolysis from over-rapid correction.
Question 12 of 30
Which statement about IV potassium chloride (KCl) is correct?
Correct! KCl is never pushed (cardiac arrest risk); it must be diluted, infused slowly, and the IV site watched for burning/infiltration. Assess renal function first.
Question 13 of 30
A client on a low-sodium diet has family bringing food. Which item is appropriate?
Correct! Broiled chicken is lean and unprocessed (low sodium). Pickles, sausage, and frozen dinners are all high-sodium.
Question 14 of 30
Which is the most common complication of TPN, requiring close monitoring?
Correct! TPN is high-dextrose, so hyperglycemia is the most common complication — monitor blood glucose.
Question 15 of 30
During TPN via a central line, the client reports sudden lightheadedness and shortness of breath. What is the FIRST action?
Correct! These symptoms suggest an air embolism — clamp the catheter and position Trendelenburg (left side) to trap air in the right atrium. Do not flush.
Question 16 of 30
Which finding in a client on continuous enteral feedings should prompt the nurse to notify the provider?
Correct! Distension + hypoactive bowel sounds suggest delayed gastric emptying/ileus or intolerance — a real concern. A 15 mL residual and occasional loose stool are within normal limits.
Question 17 of 30
How do antacids work, and what is their key limitation?
Correct! Antacids neutralize what is already there (temporary relief) — they do not reduce production, so they won’t heal an ulcer on their own.
Question 18 of 30
What is the scientific rationale for prescribing a proton pump inhibitor for GERD?
Correct! PPIs inhibit the proton pump (H+/K+-ATPase), the enzyme that produces gastric acid — the strongest acid suppression. Neutralizing, blocking H2, and coating describe antacids, H2 blockers, and sucralfate respectively.
Question 19 of 30
A client on long-term PPI therapy asks about risks. What should the nurse include?
Correct! Long-term PPIs reduce calcium absorption (fracture/osteoporosis risk) and reduce acid needed for B12 absorption (B12 deficiency).
Question 20 of 30
How should a client take sucralfate for a duodenal ulcer?
Correct! Sucralfate forms its protective barrier best on an empty stomach (1 hour before meals) and should not be taken with antacids.
Question 21 of 30
What is the role of misoprostol in peptic ulcer therapy, and what is its critical contraindication?
Correct! Misoprostol is a prostaglandin analog that boosts mucus and bicarbonate to protect the mucosa — and it is contraindicated in pregnancy (prostaglandin-induced contractions).
Question 22 of 30
A client taking bismuth subsalicylate notices black stools and is alarmed. What should the nurse say?
Correct! Bismuth subsalicylate commonly causes harmless black stools (and tongue). It also contains salicylate, so it is avoided with aspirin allergy.
Question 23 of 30
Which is the FIRST-LINE treatment for constipation in an otherwise healthy adult?
Correct! Bulk-forming laxatives (psyllium) are first-line — they absorb water and form soft, bulky stool without the harsh effects of stimulants.
Question 24 of 30
Which client is the best candidate for methylnaltrexone?
Correct! Methylnaltrexone treats opioid-induced constipation in clients on long-term/high-dose opioids who haven’t responded to usual laxatives.
Question 25 of 30
When should ondansetron be given for a client about to receive an emetogenic antibiotic?
Correct! Ondansetron is a preventive antiemetic — give it BEFORE the nauseating agent. Also caution with QT prolongation/cardiac conduction issues.
Question 26 of 30
Which lab result should make the nurse question sulfasalazine administration?
Correct! Sulfasalazine can cause bone marrow suppression → leukopenia. A low WBC (and pre-existing liver disease) both warrant questioning/holding the drug.
Question 27 of 30
Which history finding is a contraindication to combined oral contraceptives?
Correct! Smoking + hypertension markedly raises the thromboembolic risk of oral contraceptives — a contraindication. Allergies, hypothyroidism, and low cholesterol are not.
Question 28 of 30
A client requests emergency contraception after a condom broke. What is the MOST important question to ask first?
Correct! Time since intercourse determines which method still works (levonorgestrel ≤72 h; ulipristal ≤5 days). Timing is the deciding factor.
Question 29 of 30
Which substance should a client on estradiol be taught to AVOID?
Correct! Smoking raises thromboembolic risk and grapefruit juice inhibits estradiol metabolism — both should be avoided. Green tea, dairy, and leafy greens are fine.
Question 30 of 30
Which client statement indicates understanding of norethindrone teaching?
Correct! Progestin-only pills (norethindrone) must be taken at the same time daily — missed/irregular doses cause contraceptive failure.
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