What does the -pril suffix indicate in a drug name?

The -pril suffix identifies ACE inhibitors (angiotensin-converting enzyme inhibitors). Examples include lisinopril, enalapril, benazepril, and ramipril. ACE inhibitors are used for hypertension, heart failure, and diabetic nephropathy. A characteristic class-wide side effect is a dry, nonproductive cough caused by bradykinin accumulation.

What drug is the first-line treatment for Type 2 Diabetes Mellitus?

Metformin (brand name Glucophage) is the first-line oral medication for Type 2 Diabetes Mellitus. It is a biguanide that decreases hepatic glucose output. It does not cause hypoglycemia when used alone. Key caution: metformin must be held before and 48 hours after IV contrast dye procedures due to risk of lactic acidosis from contrast-induced kidney injury.

What are DAW codes in pharmacy?

DAW (Dispense As Written) codes are numeric codes 0–9 used in pharmacy to indicate whether generic substitution is permitted. DAW 0 means no restriction — generic substitution is allowed (the default). DAW 1 means the prescriber requires the brand-name drug only. DAW 2 means the patient has requested the brand-name product. DAW 8 means no generic equivalent is available on the market.

What is the difference between DAW 1 and DAW 2?

DAW 1 means the prescriber requires the brand-name drug — the pharmacy cannot substitute a generic without prescriber authorization. This is typically documented with language like 'brand medically necessary.' DAW 2 means the patient has requested the brand-name product even though the prescriber did not restrict substitution. The patient may pay the cost difference between brand and generic.

Which drug suffix identifies beta-blockers?

The -olol suffix identifies beta-blockers (beta-adrenergic receptor antagonists). Examples include metoprolol, atenolol, propranolol, carvedilol, and bisoprolol. Beta-blockers are used for hypertension, angina, heart failure, and post-MI care. Key counseling: never stop beta-blockers abruptly — risk of rebound angina or myocardial infarction. They also mask hypoglycemia symptoms in diabetic patients.

What drug class do -statin drugs belong to, and what are the key side effects?

Drugs ending in -statin are HMG-CoA reductase inhibitors (statins), which lower LDL cholesterol by blocking hepatic cholesterol synthesis. Common examples include atorvastatin (Lipitor), simvastatin (Zocor), and rosuvastatin (Crestor). Key side effects include myopathy (muscle pain or weakness) and, rarely, rhabdomyolysis. Grapefruit juice should be avoided with simvastatin and lovastatin as it inhibits CYP3A4 and raises drug levels.

What is an AB-rated generic drug?

An AB-rated generic drug has been determined by the FDA (via the Orange Book) to be therapeutically equivalent to its brand-name reference drug. This means it contains the same active ingredient, strength, dosage form, and route of administration, and has demonstrated bioequivalence. Pharmacists may substitute AB-rated generics for brand-name drugs unless a DAW code or state law restricts it.

Drug Classifications & Top 200 Drugs

The Four Drug Knowledge Pillars

Drug classifications and Top 200 knowledge spans these four interconnected areas on the PTCE

Drug Classifications

Therapeutic & Pharmacological Classes

Drugs are grouped by what they treat (therapeutic class: antihypertensives, antibiotics) and by how they work (pharmacological class: ACE inhibitors, beta-blockers). The PTCE tests both. Knowing a drug's class tells you its mechanism, common side effects, and counseling points.

20+

Major Classes

MOA

Mechanism Key

Top 200 Drugs

Most Prescribed Medications

The Top 200 drugs account for the vast majority of prescriptions dispensed in the U.S. The PTCE heavily tests these — you must know each drug's generic name, brand name(s), drug class, primary indication, and key counseling points. Statins, ACE inhibitors, and SSRIs dominate the list.

200

Must-Know Drugs

Rx #1

Most Dispensed

Drug Name Stems & Suffixes

Decode Any Drug Name

Pharmaceutical naming conventions embed the drug class into the generic name. Learning stems like -pril (ACE inhibitors), -olol (beta-blockers), -statin (HMG-CoA inhibitors), and -sartan (ARBs) lets you identify an unknown drug's class instantly — a major PTCE time-saver.

-pril

ACE Inhibitor

-olol

Beta-Blocker

Brand vs. Generic

Substitution Rules & DAW Codes

Generic substitution saves patients money and is the default in most states. DAW (Dispense As Written) codes 0–9 control whether substitution is permitted. DAW 0 = substitution allowed. DAW 1 = prescriber requires brand. The PTCE tests DAW codes and substitution scenarios directly.

DAW

0–9 Codes

Equivalent Rating

Drug Name Stems — Quick Reference

-pril

ACE Inhibitor

lisinopril, enalapril, benazepril, ramipril

-sartan

ARB (Angiotensin Receptor Blocker)

losartan, valsartan, irbesartan, olmesartan

-olol

Beta-Blocker (β-blocker)

metoprolol, atenolol, propranolol, carvedilol

-dipine

Calcium Channel Blocker (CCB)

amlodipine, nifedipine, felodipine

-statin

HMG-CoA Reductase Inhibitor (Statin)

atorvastatin, simvastatin, rosuvastatin

-prazole

Proton Pump Inhibitor (PPI)

omeprazole, pantoprazole, lansoprazole

-tidine

H2 Receptor Antagonist

famotidine, ranitidine (recalled), cimetidine

-cillin

Penicillin Antibiotic

amoxicillin, ampicillin, oxacillin, dicloxacillin

-mycin / -micin

Macrolide / Aminoglycoside Antibiotic

azithromycin, clarithromycin, gentamicin

-floxacin

Fluoroquinolone Antibiotic

ciprofloxacin, levofloxacin, moxifloxacin

-cycline

Tetracycline Antibiotic

doxycycline, tetracycline, minocycline

-zepam / -zolam

Benzodiazepine

lorazepam, diazepam, clonazepam; alprazolam

-triptan

Serotonin Agonist (Migraine)

sumatriptan, rizatriptan, eletriptan

-setron

5-HT3 Antagonist (Antiemetic)

ondansetron, granisetron, dolasetron

-mab

Monoclonal Antibody (Biologic)

adalimumab, trastuzumab, bevacizumab

-parin

Heparin / Low Molecular Weight Heparin

heparin, enoxaparin, dalteparin

-oxacin

Fluoroquinolone (alternate stem)

same class as -floxacin; ofloxacin

-gliptin

DPP-4 Inhibitor (Antidiabetic)

sitagliptin, saxagliptin, linagliptin

💡

Stem strategy: On the PTCE, if you see an unfamiliar generic drug name, look for the stem. A drug ending in -olol is almost certainly a beta-blocker. A drug ending in -statin is a cholesterol drug. This alone can eliminate wrong answers and identify counseling points without memorizing every drug individually.

How It Works

Key drug classes, Top 200 high-yield drugs, generic substitution rules, and DAW codes explained

Drug Classifications

Major Therapeutic Classes & Mechanisms

Antihypertensives — 4 Major Classes

ACE inhibitors (-pril): Block conversion of angiotensin I → II. Lower blood pressure and protect kidneys. SE: dry cough (class effect), hyperkalemia, angioedema. Do NOT use in pregnancy. ARBs (-sartan): Block angiotensin II receptors. Similar to ACE inhibitors but NO cough. Beta-blockers (-olol): Block β-adrenergic receptors. Lower heart rate and BP. CCBs (-dipine): Block calcium channels in vascular smooth muscle. Common SE: peripheral edema.

Statins — Cholesterol-Lowering Drugs

HMG-CoA reductase inhibitors (-statin) block cholesterol synthesis in the liver. Lower LDL ("bad" cholesterol) and reduce cardiovascular event risk. Key SE: myopathy (muscle pain), rhabdomyolysis (rare), elevated liver enzymes. Avoid grapefruit juice with lovastatin and simvastatin. Take at bedtime (most cholesterol made at night). Most statins have an -astatin suffix — not just -statin (e.g., atorvastatin, rosuvastatin).

Antidiabetics — Multiple Mechanisms

Metformin (biguanide): First-line for Type 2 DM. Decreases hepatic glucose output. Do NOT use with IV contrast dye (hold before and after). SE: GI upset, lactic acidosis (rare). Sulfonylureas (-ide: glipizide, glimepiride, glyburide): Stimulate insulin release. Risk of hypoglycemia. Insulin: Various types (rapid, short, intermediate, long-acting). GLP-1 agonists (-tide: semaglutide, liraglutide): Incretin mimetics; weight loss benefit. SGLT2 inhibitors (-flozin: empagliflozin, dapagliflozin): Block glucose reabsorption in kidneys.

Antibiotics — Key Classes

Penicillins (-cillin): Cell wall synthesis inhibitors. Risk of allergic reaction; cross-allergy with cephalosporins possible. Fluoroquinolones (-floxacin): DNA gyrase inhibitors. Broad-spectrum. Avoid antacids (chelation). Risk of tendon rupture; QT prolongation. Tetracyclines (-cycline): Protein synthesis inhibitors. Avoid dairy, antacids, sun exposure (photosensitivity). Macrolides (-mycin): Protein synthesis inhibitors. CYP3A4 inhibitors — many drug interactions. Cephalosporins (cef-/ceph-): Cell wall inhibitors; related to penicillins.

CNS Drugs — Antidepressants, Anxiolytics, Opioids

SSRIs: Selective serotonin reuptake inhibitors — sertraline, fluoxetine, escitalopram, paroxetine, citalopram. First-line for depression and anxiety. Black box warning: increased suicidal ideation in patients under 25. Benzodiazepines (-zepam/-zolam): Schedule IV. CNS depressants for anxiety/seizures. Risk of dependence. Opioids: Schedule II–IV. Strong analgesics (hydrocodone, oxycodone, morphine, codeine). Risk of respiratory depression, addiction. Gabapentinoids: Gabapentin, pregabalin — neuropathic pain, seizures.

Top 200 Drugs

High-Yield Drugs for the PTCE

lisinopril

Prinivil, Zestril

ACE Inhibitor

Hypertension, heart failure, post-MI, diabetic nephropathy

Stem: -pril

metoprolol

Lopressor (tartrate), Toprol-XL (succinate)

Beta-Blocker

Hypertension, angina, heart failure, post-MI

Stem: -olol · succinate = ER (never crush)

amlodipine

Norvasc

Calcium Channel Blocker

Hypertension, angina

Stem: -dipine · SE: peripheral edema

losartan

Cozaar

ARB

Hypertension, diabetic nephropathy

Stem: -sartan · no cough (unlike ACE inhibitors)

atorvastatin

Lipitor

Statin

Hyperlipidemia, cardiovascular risk reduction

Stem: -statin · #1 prescribed drug in U.S.

hydrochlorothiazide

Microzide

Thiazide Diuretic

Hypertension, edema

SE: hypokalemia, hyperuricemia

metformin

Glucophage

Biguanide (Antidiabetic)

Type 2 Diabetes Mellitus — first-line

Hold before IV contrast · GI side effects

levothyroxine

Synthroid, Levoxyl

Thyroid Hormone

Hypothyroidism

Take on empty stomach; NTI drug — narrow dosing

omeprazole

Prilosec

Proton Pump Inhibitor

GERD, peptic ulcer disease, H. pylori

Stem: -prazole · take 30–60 min before eating

pantoprazole

Protonix

Proton Pump Inhibitor

GERD, erosive esophagitis, Zollinger-Ellison

Stem: -prazole · IV and oral formulations

ondansetron

Zofran

5-HT3 Antagonist (Antiemetic)

Nausea/vomiting (chemo, surgery, pregnancy)

Stem: -setron · ODT available

amoxicillin

Amoxil

Penicillin Antibiotic

Bacterial infections (ear, sinus, dental, strep)

Stem: -cillin · allergy risk; suspension = shake well

sertraline

Zoloft

SSRI (Antidepressant)

Depression, OCD, PTSD, panic disorder, anxiety

Most prescribed antidepressant · BBW: suicidality under 25

escitalopram

Lexapro

SSRI (Antidepressant)

Depression, generalized anxiety disorder

S-enantiomer of citalopram · well tolerated

alprazolam

Xanax

Benzodiazepine

Anxiety disorders, panic disorder

Schedule IV · -zolam stem · dependence risk

gabapentin

Neurontin

Gabapentinoid (Anticonvulsant)

Neuropathic pain, seizures, postherpetic neuralgia

Not a controlled substance federally (varies by state)

hydrocodone/APAP

Norco, Vicodin

Opioid Analgesic

Moderate-to-severe pain

Schedule II · max APAP 4g/day · high abuse potential

amphetamine salts

Adderall

CNS Stimulant

ADHD, narcolepsy

Schedule II · no refills; new Rx required each month

warfarin

Coumadin

Anticoagulant (VKA)

DVT/PE prevention, atrial fibrillation, mechanical heart valves

NTI drug · INR monitoring · many food/drug interactions

albuterol

ProAir, Ventolin, Proventil

SABA Bronchodilator

Acute asthma/COPD bronchospasm (rescue inhaler)

Short-Acting Beta-2 Agonist · shake MDI before use

azithromycin

Zithromax, Z-Pak

Macrolide Antibiotic

Respiratory infections, STIs, community-acquired pneumonia

Stem: -mycin · CYP3A4 inhibitor · QT prolongation risk

ciprofloxacin

Cipro

Fluoroquinolone Antibiotic

UTI, respiratory, GI infections; anthrax post-exposure

Stem: -floxacin · avoid antacids; tendon rupture risk

montelukast

Singulair

Leukotriene Receptor Antagonist

Asthma (maintenance), allergic rhinitis

NOT a rescue inhaler · take in evening for asthma

apixaban

Eliquis

DOAC (Factor Xa Inhibitor)

DVT/PE, atrial fibrillation — stroke prevention

Direct Oral Anticoagulant · no routine INR monitoring

Brand vs. Generic & DAW Codes

Dispense As Written (DAW) Codes 0–9

Generic Equivalence Standard

AB-rated generic = therapeutically equivalent to brand — same active ingredient, strength, route, and bioavailability

FDA Orange Book assigns equivalence ratings · AB = therapeutically equivalent · BX = insufficient data · Pharmacists may substitute AB-rated generics unless DAW code restricts it

DAW 0

No substitution indicated

Default — pharmacist may substitute with AB-rated generic (most common)

DAW 1

Prescriber requests brand only

Physician writes "brand medically necessary" — override requires prescriber authorization

DAW 2

Patient requests brand

Patient prefers brand over generic — patient may pay the cost difference

DAW 3

Pharmacist selects brand

Pharmacist selects brand — rare clinical or patient compliance reason

DAW 4

Generic not in stock

Generic is out of stock at this pharmacy — brand dispensed instead

DAW 5

Brand dispensed at generic price

Brand name drug dispensed but priced at the generic copay level

DAW 6

Override — incentivized formulary

Override required; specific to formulary or health plan rules

DAW 7

Substitution not allowed by law

State law prohibits substitution for this drug category

DAW 8

Generic not available

No generic version exists on the market — brand is the only option

DAW 9

Other

Does not fit into any other DAW code category

ℹ️

NTI drugs and generic substitution: Some states require extra steps before substituting generics for NTI drugs (warfarin, levothyroxine, digoxin, phenytoin). Even though an AB-rated generic may be available, small differences in bioavailability between manufacturers can affect therapeutic control. Pharmacists must notify prescribers and document appropriately.

Compare

Filter by drug category to compare classes, indications, key suffixes, and PTCB exam tips

Generic (Brand)	Category	Class / Mechanism	Primary Use	Key PTCB Point
lisinopril (Prinivil/Zestril)	Cardio	ACE Inhibitor · -pril stem	Hypertension, heart failure, diabetic nephropathy	SE: dry cough (class effect), angioedema. Avoid in pregnancy.
metoprolol (Lopressor/Toprol-XL)	Cardio	Beta-Blocker (β1-selective) · -olol stem	Hypertension, angina, heart failure, post-MI	Tartrate = IR; Succinate = ER (NEVER crush). SE: bradycardia.
amlodipine (Norvasc)	Cardio	Calcium Channel Blocker (CCB) · -dipine stem	Hypertension, angina	SE: peripheral edema (pitting). Long half-life — once daily.
losartan (Cozaar)	Cardio	Angiotensin Receptor Blocker (ARB) · -sartan stem	Hypertension, diabetic nephropathy	No cough (unlike ACE inhibitors). Avoid in pregnancy.
atorvastatin (Lipitor)	Cardio	HMG-CoA Reductase Inhibitor (Statin) · -statin stem	Hyperlipidemia, CV risk reduction	Take any time of day. SE: myopathy. Avoid grapefruit (all statins).
simvastatin (Zocor)	Cardio	HMG-CoA Reductase Inhibitor (Statin) · -statin stem	Hyperlipidemia	CYP3A4 substrate — grapefruit juice contraindicated. Take at bedtime.
hydrochlorothiazide (Microzide)	Cardio	Thiazide Diuretic	Hypertension, edema	SE: hypokalemia, hyponatremia, hyperuricemia (gout risk).
warfarin (Coumadin)	Cardio	Vitamin K Antagonist (Anticoagulant)	DVT/PE, afib, mechanical valves	NTI drug. INR monitoring. Many interactions (vitamin K, CYP2C9).
apixaban (Eliquis)	Cardio	Direct Oral Anticoagulant (Factor Xa inhibitor)	DVT/PE, atrial fibrillation	No routine INR monitoring. Reversal agent: andexanet alfa.
amoxicillin (Amoxil)	Antibiotic	Penicillin · -cillin stem	Ear, sinus, dental, strep throat, community infections	Cross-allergy with cephalosporins (5–10%). Suspension: shake well.
azithromycin (Zithromax / Z-Pak)	Antibiotic	Macrolide · -mycin stem	Respiratory infections, STIs, CAP	CYP3A4 inhibitor. QT prolongation risk. Take with food if GI upset.
ciprofloxacin (Cipro)	Antibiotic	Fluoroquinolone · -floxacin stem	UTI, respiratory, GI infections, anthrax	Avoid antacids/dairy (chelation). Risk: tendon rupture, QT prolongation.
doxycycline (Vibramycin)	Antibiotic	Tetracycline · -cycline stem	Acne, Lyme disease, STIs, respiratory infections	Avoid dairy/antacids. Photosensitivity — sunscreen required. Avoid under 8 yrs.
amoxicillin/clavulanate (Augmentin)	Antibiotic	Penicillin + β-lactamase inhibitor	Sinusitis, pneumonia, UTI, skin infections	Clavulanate overcomes antibiotic resistance. GI side effects common.
trimethoprim/sulfamethoxazole (Bactrim)	Antibiotic	Sulfonamide + Dihydrofolate Reductase inhibitor	UTI, PCP prophylaxis, MRSA skin infections	Allergy to sulfa drugs is common. Stay well hydrated. Avoid in late pregnancy.
sertraline (Zoloft)	CNS / Psych	SSRI (Selective Serotonin Reuptake Inhibitor)	Depression, OCD, PTSD, panic disorder, anxiety	BBW: suicidal ideation under age 25. Takes 2–4 weeks for full effect.
escitalopram (Lexapro)	CNS / Psych	SSRI	Depression, generalized anxiety disorder (GAD)	Well tolerated; fewest drug interactions of SSRIs.
fluoxetine (Prozac)	CNS / Psych	SSRI	Depression, OCD, bulimia, panic disorder	Longest half-life of SSRIs (~4–6 days) — lower discontinuation syndrome risk.
alprazolam (Xanax)	CNS / Psych	Benzodiazepine · -zolam stem	Anxiety disorders, panic disorder	Schedule IV. High dependence potential. Do NOT stop abruptly.
gabapentin (Neurontin)	CNS / Psych	Alpha-2-delta Ca²⁺ channel ligand (Gabapentinoid)	Neuropathic pain, seizures, restless leg syndrome	Not a controlled substance federally (scheduled in some states). SE: sedation, dizziness.
hydrocodone/APAP (Norco/Vicodin)	CNS / Psych	Opioid Analgesic (Opioid Agonist)	Moderate-to-severe pain	Schedule II — no refills. Max APAP 4 g/day (3 g/day elderly). BBW: respiratory depression.
amphetamine salts (Adderall)	CNS / Psych	CNS Stimulant	ADHD, narcolepsy	Schedule II — new Rx required monthly. Written prescription only in most states.
metformin (Glucophage)	Metabolic	Biguanide (Antidiabetic)	Type 2 Diabetes Mellitus — first-line treatment	Hold 48 hrs before/after IV contrast. SE: GI upset, lactic acidosis (rare). No hypoglycemia alone.
levothyroxine (Synthroid/Levoxyl)	Metabolic	Synthetic Thyroid Hormone (T4)	Hypothyroidism	NTI drug. Take on empty stomach 30–60 min before breakfast. Separate from antacids, calcium, iron.
glipizide (Glucotrol)	Metabolic	Sulfonylurea (Antidiabetic)	Type 2 Diabetes Mellitus	Take 30 min before meal. SE: hypoglycemia (key risk), weight gain. -glipide/-ide stem.
insulin glargine (Lantus)	Metabolic	Long-Acting Insulin Analog	Type 1 and Type 2 DM (basal insulin)	Clear solution; do NOT mix with other insulins. Once daily at same time. Onset 1–2 hr; duration 24 hr.
omeprazole (Prilosec)	GI	Proton Pump Inhibitor (PPI) · -prazole stem	GERD, PUD, H. pylori (with antibiotics)	Take 30–60 min before first meal. Long-term use: ↓ Mg²⁺, ↓ Ca²⁺ absorption, C. diff risk.
albuterol (ProAir/Ventolin)	Pulm	SABA (Short-Acting Beta-2 Agonist)	Acute asthma/COPD bronchospasm — rescue	Shake MDI before each use. Prime before first use. SE: tremor, tachycardia.
ondansetron (Zofran)	GI	5-HT3 Receptor Antagonist · -setron stem	Nausea/vomiting (chemo, surgery, pregnancy)	Available as oral, ODT, and IV. Can cause QT prolongation in high doses.
montelukast (Singulair)	Pulm	Leukotriene Receptor Antagonist	Asthma maintenance, allergic rhinitis	NOT a rescue inhaler. BBW: neuropsychiatric events (mood changes, suicidal thoughts).

Real Examples

Clinical scenarios showing how drug classification knowledge applies in everyday pharmacy practice

Drug Classifications

Identifying a Drug's Class From Its Name — ACE Inhibitor Dry Cough

A patient calls the pharmacy complaining of a persistent dry cough that started 2 weeks after beginning lisinopril 10 mg. They ask if the cough is related to the medication.

Lisinopril ends in -pril → ACE inhibitor class. ACE (angiotensin-converting enzyme) breaks down bradykinin in the lungs.
ACE inhibitors block ACE → bradykinin accumulates in the lungs → triggers a dry, nonproductive cough in 10–20% of patients
This is a CLASS EFFECT — it occurs with ALL ACE inhibitors (-pril drugs), not just lisinopril
The pharmacist should advise the patient to contact their prescriber — an ARB (-sartan) is a common therapeutic alternative that does NOT cause cough (it acts on the receptor, not the enzyme)
Do NOT tell the patient to stop the medication without prescriber approval

✅ Key point: -pril = ACE inhibitor = dry cough class effect. Alternative = -sartan (ARB), same indication, no cough.

Top 200 Drugs

Metformin and IV Contrast — Knowing When to Hold the Drug

A patient with Type 2 DM on metformin 1000 mg BID is scheduled for a CT scan with contrast dye tomorrow. The pharmacy gets a call asking if the patient should take their metformin.

Metformin (Glucophage) is a biguanide — first-line antidiabetic. It is renally cleared unchanged.
Iodinated IV contrast dye can cause acute kidney injury (AKI) in some patients. Even a small, temporary drop in GFR can impair metformin excretion.
Accumulated metformin → elevated plasma levels → increased risk of LACTIC ACIDOSIS (potentially fatal)
Standard guidance: Hold metformin on the day of the contrast procedure and for 48 hours after. Restart only after confirming kidney function remains normal.
The pharmacist should confirm this guidance and recommend the patient contact their prescriber about alternative diabetes management for the 48-hour window

✅ Key point: Metformin + IV contrast = hold 48 hrs. Reason: AKI risk → lactic acidosis. Classic PTCB drug interaction scenario.

Drug Name Stems

Using a Drug Suffix to Identify Class and Counsel a Patient

A new prescription arrives for "atenolol 50 mg once daily." The patient says they've never heard of it and asks what it does. You don't have the patient's chart in front of you.

Step 1: Identify the stem. Atenolol ends in -olol → this is a beta-blocker (β-adrenergic receptor antagonist)
Step 2: From the class, you know: beta-blockers are used for hypertension, angina, heart failure, arrhythmias, and post-MI care
Step 3: Key counseling points apply to the entire -olol class: do NOT stop abruptly (risk of rebound angina or MI); can mask hypoglycemia symptoms in diabetics; SE: bradycardia, fatigue, cold extremities
Step 4: You can now give accurate counseling even without knowing the specific indication — because the class tells you what to watch for
This stem strategy works across the board: -pril → ACE inhibitor counseling; -statin → cholesterol counseling + myopathy warning; -prazole → take before meals

✅ Key point: -olol stem = beta-blocker. Never stop abruptly. Masks hypoglycemia. Stem knowledge unlocks counseling for any -olol drug.

Brand vs. Generic / DAW Codes

DAW Code 1 vs. DAW Code 2 — Who's Requesting Brand?

Two prescriptions come in for Synthroid (levothyroxine) 100 mcg. Prescription A has "Synthroid — brand medically necessary" handwritten by the physician. Prescription B has no special notation, but the patient insists on receiving Synthroid, not the generic.

Prescription A: The prescriber has documented brand-only. This is DAW 1 — Prescriber requests brand only. Dispensing the generic without prescriber authorization is not permitted.
Prescription B: The prescriber did not restrict substitution, but the patient wants brand. This is DAW 2 — Patient requests brand. Substitution is otherwise allowed, but the patient is choosing to pay the brand price difference.
Levothyroxine is an NTI drug — even small differences between manufacturers can affect TSH levels (thyroid control). This is why many physicians and patients prefer brand consistency.
In many states, generic substitution for NTI drugs like levothyroxine requires prescriber notification and documentation
Bottom line: DAW 1 = prescriber says brand. DAW 2 = patient says brand. Both prevent generic substitution, but for different reasons and with different insurance billing implications.

✅ Key point: DAW 1 = prescriber requires brand. DAW 2 = patient requests brand. Levothyroxine is NTI — brand consistency matters.

Practice Quiz

10 PTCE-style questions on drug classes, Top 200, stems, and DAW codes — with instant explanations

Question 1 of 10

Classes

—

Top 200

—

Stems

—

DAW/Brand

—

Drug Finder

Use this tool to identify drug classes, decode name stems, or look up DAW code guidance

What do you need help identifying?

Memory Hooks

Click any card to flip it — 8 high-yield drug classification mnemonics for the PTCE

💊

-pril suffix → what drug class?

Tap to reveal →

ACE Inhibitor

lisinopril, enalapril, benazepril, ramipril. Key SE: dry cough (class effect) + angioedema. No pregnancy. -sartan is the alternative.

❤️

-olol suffix → what drug class?

Tap to reveal →

Beta-Blocker (β-blocker)

metoprolol, atenolol, propranolol, carvedilol. Never stop abruptly. Masks hypoglycemia. Metoprolol tartrate = IR; succinate = ER (never crush).

📊

-statin suffix → what class, and what's the key SE?

Tap to reveal →

Statin — HMG-CoA Reductase Inhibitor

atorvastatin, simvastatin, rosuvastatin. Key SE: myopathy (muscle pain), rhabdomyolysis. Avoid grapefruit with simvastatin/lovastatin.

🧬

-sartan suffix → what class, and how does it differ from -pril?

Tap to reveal →

ARB — Angiotensin Receptor Blocker

losartan, valsartan, irbesartan. Same indications as ACE inhibitors. KEY difference: ARBs do NOT cause dry cough (no bradykinin accumulation).

💉

What is the #1 most prescribed drug in the U.S.?

Tap to reveal →

Atorvastatin (Lipitor)

Statin (HMG-CoA reductase inhibitor). Treats hyperlipidemia and reduces cardiovascular event risk. Consistently the most prescribed brand in the U.S.

🔢

DAW 1 vs DAW 2 — what's the difference?

Tap to reveal →

DAW 1 = Prescriber requires brand · DAW 2 = Patient requests brand

Both prevent generic substitution. DAW 0 = substitution allowed (default). DAW 8 = no generic available on market.

😟

Metformin must be HELD before what procedure?

Tap to reveal →

IV Contrast Dye Procedures (CT Scans)

Hold metformin on the day of IV contrast and 48 hrs after. Contrast → AKI risk → metformin accumulates → lactic acidosis. Restart only after confirming normal renal function.

😴

-zepam / -zolam suffix → what class and schedule?

Tap to reveal →

Benzodiazepines — Schedule IV

lorazepam, diazepam, clonazepam (-zepam); alprazolam, triazolam (-zolam). CNS depressants. Do NOT stop abruptly — risk of seizures and withdrawal. High dependence potential.

Drug Classifications & Top 200 Drugs

Therapeutic & Pharmacological Classes

Most Prescribed Medications

Decode Any Drug Name

Substitution Rules & DAW Codes

Drug Name Stems — Quick Reference

Antihypertensives — 4 Major Classes

Statins — Cholesterol-Lowering Drugs

Antidiabetics — Multiple Mechanisms

Antibiotics — Key Classes

CNS Drugs — Antidepressants, Anxiolytics, Opioids

Identifying a Drug's Class From Its Name — ACE Inhibitor Dry Cough

Metformin and IV Contrast — Knowing When to Hold the Drug

Using a Drug Suffix to Identify Class and Counsel a Patient

DAW Code 1 vs. DAW Code 2 — Who's Requesting Brand?

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