5 Drug Suffix Patterns That Unlock NCLEX Pharmacology (With Mnemonics and Practice Questions)

Pharmacology asks you to recognize hundreds of drugs, but you do not have to memorize them one by one. The FDA requires generic drug names to contain a stem that identifies the drug class, so if you learn the stem you can identify any drug in that class — even brand-new ones you have never studied. Master these five suffixes and you will recognize entire drug classes on sight.

1. The "-olol" suffix: beta-blockers

Drugs ending in -olol are beta-adrenergic antagonists (beta-blockers) — for example metoprolol, atenolol, propranolol, carvedilol, and labetalol. They block beta-1 and/or beta-2 adrenergic receptors, slowing heart rate and reducing blood pressure; think of them as a speed limiter on the heart. Mnemonic — "LOL, my heart is slow": when you see -olol, picture laughing so hard (LOL) that your heart slows down, so if a patient on an -olol drug has a HR below 60, hold the med and notify the provider. On the NCLEX, a patient on metoprolol with a HR of 54 bpm and BP of 108/68 mmHg calls for holding the dose and notifying the provider, because 54 bpm is below the safe threshold of 60 and giving the drug would further suppress cardiac output.

• Always check HR before administration — hold if HR < 60 bpm
• Monitor for orthostatic hypotension
• Never stop abruptly (rebound tachycardia)
• Mask hypoglycemia symptoms in diabetic patients

2. The "-pril" suffix: ACE inhibitors

Drugs ending in -pril are angiotensin-converting enzyme (ACE) inhibitors — for example lisinopril, enalapril, captopril, ramipril, and benazepril. They block the conversion of angiotensin I to angiotensin II, reducing vasoconstriction and aldosterone secretion to lower blood pressure and cardiac workload. Mnemonic — "a -pril a day keeps the pressure away, but gives you a DRY cough": the hallmark side effect is a persistent, dry cough from bradykinin accumulation, and if a patient cannot tolerate it, the classic move is to switch them to an ARB (-sartan). NCLEX twist: when a patient on lisinopril has both a 3-week dry cough and a potassium of 5.6 mEq/L, report the potassium first — both are expected, but 5.6 mEq/L is dangerously above the normal 3.5–5.0 range and risks cardiac dysrhythmias.

• Monitor for persistent dry cough (most common reason for discontinuation)
• Watch potassium levels — ACE inhibitors cause hyperkalemia
• Assess for angioedema (swelling of face, lips, tongue) — this is an emergency
• Contraindicated in pregnancy (teratogenic)

3. The "-sartan" suffix: ARBs (angiotensin II receptor blockers)

Drugs ending in -sartan are angiotensin II receptor blockers (ARBs) — for example losartan, valsartan, irbesartan, candesartan, and olmesartan. They block angiotensin II at the receptor site instead of blocking its production like ACE inhibitors, giving the same blood pressure-lowering effect without the dry cough. Mnemonic — "can't stand the -pril? Switch to -sartan": when a patient on an ACE inhibitor has a persistent dry cough, the expected NCLEX intervention is switching to an ARB, which blocks the same system downstream for the same benefit with no cough. The catch tested on exam: ARBs still cause hyperkalemia, so a patient switched from enalapril to losartan should keep avoiding potassium supplements and salt substitutes, which contain potassium chloride.

• First-line alternative for patients who can't tolerate ACE inhibitor cough
• Still causes hyperkalemia — monitor potassium
• Still contraindicated in pregnancy
• Monitor renal function (BUN/creatinine)

4. The "-statin" suffix: HMG-CoA reductase inhibitors

Drugs ending in -statin are HMG-CoA reductase inhibitors (statins) — for example atorvastatin, rosuvastatin, simvastatin, pravastatin, and lovastatin. They block the enzyme that produces cholesterol in the liver, lowering LDL ("bad" cholesterol), raising HDL ("good" cholesterol), and reducing cardiovascular risk. Mnemonic — "statins STAY in at night and hate grapefruit": statins are taken at bedtime because cholesterol production peaks overnight, and grapefruit juice inhibits the CYP3A4 enzyme that metabolizes them, causing toxic drug levels. NCLEX red flag: a patient on atorvastatin with severe muscle pain and dark-colored urine should have the drug held and the provider notified immediately, because that picture suggests rhabdomyolysis — a potentially fatal muscle breakdown that can cause acute kidney injury.

• Take at bedtime (cholesterol synthesis peaks at night)
• Monitor liver function tests (LFTs) — hepatotoxicity risk
• Teach patient to report unexplained muscle pain (rhabdomyolysis)
• Avoid grapefruit juice (inhibits CYP3A4, increases drug levels)

5. The "-pam" and "-lam" suffixes: benzodiazepines

Drugs ending in -pam or -lam are benzodiazepines (anxiolytics/sedatives) — for example diazepam, lorazepam, clonazepam, alprazolam, and midazolam. They enhance GABA activity in the CNS, producing sedation, anxiolysis, muscle relaxation, and anticonvulsant effects. Mnemonic — "PAM and LAM take the cALM exam": -pam or -lam should make you think sedation, fall risk, and respiratory depression — and always know the antidote, flumazenil, the answer for benzodiazepine overdose. NCLEX scenario: a patient given IV lorazepam for status epilepticus who drops to a respiratory rate of 8 breaths/min and an oxygen saturation of 89% needs flumazenil as prescribed plus airway support, because respiratory depression is the most dangerous adverse effect and flumazenil is the specific antagonist.

• Monitor respiratory status — CNS depression risk
• Fall precautions (sedation + muscle relaxation = fall risk)
• Antidote: flumazenil (know this for NCLEX)
• Avoid alcohol and other CNS depressants
• Taper slowly — abrupt withdrawal causes seizures

The master pattern: your suffix cheat sheet

How to lock these in: active recall strategy

Pharmacology does not have to be overwhelming. Learn the patterns. Practice the application. Trust the process.