10.1 Key Canadian Drug Classes, Common Indications & Canadian Brand/Generic Names

Key Canadian Drug Classes, Common Indications & Canadian Brand/Generic Names

Exam Tip: In the OpenExamPrep independent study guide for the PEBC Pharmacy Technician Qualifying Examination, candidates must demonstrate fluent command of Canadian generic and brand names, mechanisms of action, approved therapeutic indications, major side effects, and essential auxiliary label warnings. Be especially mindful of differences between Canadian drug naming conventions and international terminology (e.g., salbutamol vs. albuterol, acetaminophen vs. paracetamol, Cipralex vs. Lexapro).

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Distinctive Canadian Nomenclature & Equivalencies

Pharmacy technicians practicing in Canada encounter unique brand and generic names that differ substantially from United States (USP) and international (INN) conventions. Misinterpreting these names can lead to grave order entry errors, incorrect product selection, or dangerous duplicate therapies.

Key Canadian vs. International Generic and Brand Equivalents

1. Acetaminophen vs. Paracetamol: In Canada and the United States, the non-proprietary generic name is acetaminophen (common Canadian brand: Tylenol). In the United Kingdom, Europe, Australia, and the International Pharmacopoeia, the exact same molecule is named paracetamol. When processing medical records or international traveler prescriptions, technicians must recognize that paracetamol is acetaminophen, preventing accidental cumulative overdoses exceeding the recommended maximum of 4,000 mg daily (or 2,000 to 3,000 mg in older adults or hepatic impairment).
2. Salbutamol vs. Albuterol: In Canada, the short-acting beta-2 agonist bronchodilator is officially designated salbutamol (common Canadian brand: Ventolin). In the United States, this drug is named albuterol (ProAir, Ventolin HFA, Proventil). They are identical active chemical entities.
3. Dimenhydrinate (Gravol): In Canada, dimenhydrinate is universally recognized by the household brand name Gravol. In the United States, dimenhydrinate is commonly branded as Dramamine.
4. Escitalopram (Cipralex vs. Lexapro): In Canada, the brand name for the selective serotonin reuptake inhibitor escitalopram is Cipralex. In the United States, it is marketed as Lexapro.
5. Ramipril (Altace): The first-line ACE inhibitor ramipril is marketed under the brand name Altace across Canada.
6. Pantoprazole (Pantoloc vs. Protonix): In Canada, the proton pump inhibitor pantoprazole sodium is branded as Pantoloc (or pantoprazole magnesium as Tecta). In the United States, pantoprazole is branded as Protonix.
7. Glyburide vs. Glibenclamide: In Canada and the US, this second-generation sulfonylurea is called glyburide (Canadian brand: DiaBeta). In British and international nomenclature, it is known as glibenclamide.
8. Furosemide (Lasix): Widely utilized loop diuretic maintaining the same generic and brand across North America, though technicians must watch for look-alike sound-alike confusion with Losec (omeprazole).

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Cardiovascular Pharmacotherapy

Cardiovascular medications represent the highest volume of chronic prescriptions dispensed in Canadian community and hospital pharmacies. Technicians must understand their pharmacology to identify dosage form issues, therapeutic duplications, and required auxiliary labeling.

┌─────────────────────────────────────────────────────────────────────────┐
│                     Cardiovascular Drug Class Overview                  │
├──────────────────────────┬──────────────────────┬───────────────────────┤
│ Drug Class               │ Suffix / Examples    │ Key Canadian Brands   │
├──────────────────────────┼──────────────────────┼───────────────────────┤
│ ACE Inhibitors           │ -pril (Ramipril,     │ Altace, Coversyl,     │
│                          │ Perindopril)         │ Vasotec               │
├──────────────────────────┼──────────────────────┼───────────────────────┤
│ Angiotensin Receptor     │ -sartan (Candesartan,│ Atacand, Diovan,      │
│ Blockers (ARBs)          │ Valsartan, Losartan) │ Cozaar                │
├──────────────────────────┼──────────────────────┼───────────────────────┤
│ Beta-Adrenergic Blockers │ -olol (Bisoprolol,   │ Monocor, Lopresor,    │
│                          │ Metoprolol, Atenolol)│ Tenormin              │
├──────────────────────────┼──────────────────────┼───────────────────────┤
│ Calcium Channel Blockers │ -dipine (Amlodipine, │ Norvasc, Adalat XL;   │
│ (DHP and non-DHP)        │ Nifedipine); dilti-  │ non-DHP: Cardizem CD, │
│                          │ azem, verapamil      │ Isoptin SR            │
├──────────────────────────┼──────────────────────┼───────────────────────┤
│ HMG-CoA Reductase Inhib. │ -statin (Atorvastatin│ Lipitor, Crestor,     │
│ (Statins)                │ Rosuvastatin)        │ Zocor                 │
├──────────────────────────┼──────────────────────┼───────────────────────┤
│ Anticoagulants (DOACs    │ -xaban (Apixaban,    │ Eliquis, Xarelto,     │
│ & Warfarin)              │ Rivaroxaban), Warfarin│ Coumadin              │
└──────────────────────────┴──────────────────────┴───────────────────────┘

1. Renin-Angiotensin-Aldosterone System (RAAS) Inhibitors

• ACE Inhibitors (Angiotensin-Converting Enzyme Inhibitors):
  • Examples: Ramipril (Altace), perindopril (Coversyl), enalapril (Vasotec), lisinopril (Zestril).
  • Mechanism of Action: Competitively inhibit ACE, preventing the conversion of angiotensin I to the potent vasoconstrictor angiotensin II. This reduces aldosterone secretion, lowering systemic vascular resistance and blood pressure while decreasing cardiac afterload.
  • Indications: Essential hypertension, congestive heart failure, post-myocardial infarction, diabetic nephropathy.
  • Adverse Effects: Persistent dry non-productive cough (caused by accumulation of bradykinin, occurring in up to 15-20% of patients), hyperkalemia, acute renal decline, and rare life-threatening angioedema (swelling of the lips, tongue, and glottis).
  • Auxiliary Warnings: Avoid potassium supplements or potassium-based salt substitutes unless directed by a prescriber; report facial or throat swelling immediately.
• Angiotensin II Receptor Blockers (ARBs):
  • Examples: Candesartan (Atacand), valsartan (Diovan), losartan (Cozaar), telmisartan (Micardis).
  • Mechanism of Action: Selectively block the AT1 receptor subtype, preventing angiotensin II binding without inhibiting bradykinin breakdown. They do not cause the dry bradykinin cough and are preferred alternatives for patients who develop an ACE-inhibitor cough.
  • Adverse Effects: Dizziness, hyperkalemia, hypotension, rare angioedema.

2. Beta-Adrenergic Blockers

• Examples: Bisoprolol (Monocor), metoprolol tartrate (Lopresor, Lopresor SR), atenolol (Tenormin), carvedilol, propranolol.
• Mechanism of Action: Competitively antagonize beta-1 receptors in cardiac tissue (cardioselective: bisoprolol, metoprolol, atenolol), reducing heart rate, myocardial contractility, and cardiac output. Non-selective beta-blockers (propranolol) also block beta-2 receptors in bronchial smooth muscle.
• Indications: Hypertension, stable angina pectoris, post-MI secondary prevention, rate control in atrial fibrillation, chronic heart failure.
• Adverse Effects: Bradycardia, fatigue, cold extremities, orthostatic hypotension, bronchospasm (in asthmatic patients taking non-selective agents), sexual dysfunction, and masking of hypoglycemic warning symptoms (tachycardia and tremors) in diabetic patients (sweating is typically not masked).
• Critical Warning: Do not discontinue abruptly. Abrupt cessation can precipitate rebound severe hypertension, acute angina, or myocardial infarction.

3. Calcium Channel Blockers (CCBs)

• Dihydropyridines: Amlodipine (Norvasc), nifedipine (Adalat XL), felodipine (Plendil).
  • Mechanism: Selectively inhibit L-type calcium channels in vascular smooth muscle, causing profound peripheral arterial vasodilation.
  • Adverse Effects: Peripheral dependent edema (bilateral ankle/pedal swelling), flushing, headache, gingival hyperplasia (gum overgrowth).
• Non-Dihydropyridines: Diltiazem (Cardizem CD, Tiazac), verapamil (Isoptin, Isoptin SR).
  • Mechanism: Inhibit calcium channels in both vascular smooth muscle and cardiac nodal tissue (SA and AV nodes), reducing heart rate and myocardial contractility.
  • Adverse Effects: Bradycardia, AV nodal conduction delay, worsening heart failure, severe constipation (especially verapamil, affecting up to 30% of patients).
  • Interactions: Potent inhibitors of CYP3A4; interact with statins, cyclosporine, and digoxin.

4. Lipid-Lowering Agents (Statins)

• Examples: Atorvastatin (Lipitor), rosuvastatin (Crestor), simvastatin (Zocor), pravastatin (Pravachol).
• Mechanism of Action: Competitively inhibit 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme in hepatic cholesterol biosynthesis. This depletes intracellular cholesterol, upregulating cell-surface LDL receptors and clearing LDL-C from the bloodstream.
• Adverse Effects: Myalgia (muscle aches), elevated liver transaminases, rare rhabdomyolysis (muscle breakdown causing dark tea-colored urine and acute kidney injury).
• Auxiliary Warnings: Report unexplained muscle pain, tenderness, or weakness immediately; take rosuvastatin and atorvastatin at any time of day, but take short-acting statins (simvastatin, pravastatin) in the evening to match diurnal hepatic cholesterol synthesis. Avoid large quantities of grapefruit juice (especially with atorvastatin and simvastatin due to CYP3A4 inhibition).

5. Anticoagulants & Antiplatelets

• Direct Oral Anticoagulants (DOACs): Apixaban (Eliquis), rivaroxaban (Xarelto), edoxaban (Lixiana) inhibit Factor Xa; dabigatran (Pradaxa) inhibits thrombin (Factor IIa).
  • Indications: Prevention of stroke in non-valvular atrial fibrillation; treatment and secondary prevention of deep vein thrombosis (DVT) and pulmonary embolism (PE).
  • Advantages: Fixed oral dosing, predictable pharmacokinetics, rapid onset, no routine international normalized ratio (INR) blood monitoring required.
  • Administration Nuance: Rivaroxaban 15 mg and 20 mg tablets must be taken with food (specifically a substantial meal) to ensure proper gastrointestinal absorption, whereas 10 mg can be taken with or without food. Dabigatran capsules must be stored in original packaging (sensitive to moisture) and swallowed whole (never opened or chewed).
• Vitamin K Antagonist (Warfarin / Coumadin):
  • Mechanism: Inhibits vitamin K epoxide reductase, preventing activation of clotting factors II, VII, IX, and X, as well as proteins C and S.
  • Monitoring: Requires regular INR testing (standard therapeutic target: 2.0 to 3.0; mechanical mitral heart valves: 2.5 to 3.5).
  • Cautions: Highly bound to plasma proteins, extensive CYP2C9 metabolism, extensive drug and food interactions (consistent dietary intake of vitamin K from green leafy vegetables is critical).
• Antiplatelets: Acetylsalicylic acid (ASA / Aspirin - COX-1 inhibitor), clopidogrel (Plavix - P2Y12 platelet inhibitor). Used for secondary prevention of atherothrombotic events.

Central Nervous System (CNS) Pharmacotherapy

Central nervous system medications encompass antidepressants, anxiolytics, sedatives, and anticonvulsants. Pharmacy technicians must be familiar with their classifications, controlled drug schedules, and safety considerations.

1. Antidepressants (SSRIs & SNRIs)

• Selective Serotonin Reuptake Inhibitors (SSRIs):
  • Examples: Sertraline (Zoloft), escitalopram (Cipralex), citalopram (Celexa), fluoxetine (Prozac), paroxetine (Paxil).
  • Mechanism: Selectively inhibit presynaptic reuptake of serotonin (5-HT), increasing synaptic neurotransmitter availability.
  • Indications: Major depressive disorder, generalized anxiety disorder, panic disorder, obsessive-compulsive disorder (OCD), PTSD.
  • Adverse Effects: Initial nausea, gastrointestinal upset, insomnia or somnolence, sexual dysfunction (decreased libido, anorgasmia), weight changes, hyponatremia (SIADH in elderly), and potential QT prolongation (citalopram and escitalopram carry specific daily dosage caps—maximum 20 mg/day of escitalopram, or 10 mg/day in elderly/hepatic impairment).
  • Auxiliary Warnings: Full therapeutic antidepressant effect requires 2 to 6 weeks of continuous use; do not stop taking without consulting prescriber (avoids SSRI discontinuation syndrome); black box warning for increased risk of suicidal ideation in adolescents and young adults under age 25.
• Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs):
  • Examples: Venlafaxine (Effexor XR), duloxetine (Cymbalta), desvenlafaxine (Pristiq).
  • Mechanism: Dual reuptake inhibition of serotonin and norepinephrine.
  • Indications: Depression, anxiety disorders, diabetic peripheral neuropathic pain, fibromyalgia (duloxetine).
  • Adverse Effects: Similar to SSRIs plus dose-dependent elevations in blood pressure and heart rate, diaphoresis (sweating).

2. Anxiolytics & Hypnotics (Benzodiazepines & Z-Drugs)

• Examples: Lorazepam (Ativan), clonazepam (Rivotril), diazepam (Valium), alprazolam (Xanax), temazepam (Restoril), zopiclone (Imovane).
• Classification: Benzodiazepines and zolpidem are targeted substances (CDSA Schedule IV; Schedule 3 of the Controlled Substances Regulations since October 1, 2026, formerly the BOTSR). Zopiclone is not a controlled substance in Canada; it is a prescription drug only. Record-keeping, security and transfer rules apply to the targeted substances.
• Mechanism: Positive allosteric modulators of GABA-A receptors, enhancing inhibitory GABA neurotransmission.
• Adverse Effects: CNS depression, somnolence, ataxia, cognitive blunting, anterograde amnesia, respiratory depression, physical and psychological dependence, withdrawal seizures upon abrupt cessation, and elevated fall/fracture risk in seniors (Beers Criteria high-risk medication).
• Auxiliary Warnings: May cause drowsiness; avoid alcohol and other CNS depressants; do not operate motor vehicles or heavy machinery until individual effects are established.

3. Anticonvulsants & Neuropathic Pain Agents

• Gabapentin (Neurontin) & Pregabalin (Lyrica):
  • Mechanism: Bind to alpha-2-delta subunit of voltage-gated calcium channels in the CNS, dampening excitatory neurotransmitter release.
  • Indications: Neuropathic pain (diabetic neuropathy, post-herpetic neuralgia), focal seizures, generalized anxiety (pregabalin).
  • Adverse Effects: Dizziness, peripheral edema, somnolence, weight gain, potential misuse/diversion.
• Lamotrigine (Lamictal):
  • Mechanism: Voltage-gated sodium channel blocker.
  • Critical Safety Concern: Risk of severe cutaneous adverse reactions, including life-threatening Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). Requires strict, gradual dose titration schedules (starter packs). Technicians must emphasize that patients should immediately report any new skin rash, fever, or swollen lymph nodes.
• Carbamazepine (Tegretol):
  • Mechanism: Sodium channel blocker; potent hepatic autoinducer and CYP3A4 inducer.
  • Clinical Considerations: Requires therapeutic drug monitoring (a commonly used reference range is about 17 to 42 micromol/L, or 4 to 10 mcg/mL); risk of agranulocytosis, aplastic anemia, hyponatremia, and SJS/TEN.
• Valproic Acid / Divalproex Sodium (Epival):
  • Indications: Bipolar disorder, epilepsy, migraine prophylaxis.
  • Boxed Warnings: Teratogenicity (major congenital neural tube defects; contraindicated in pregnancy for migraines), hepatotoxicity, acute pancreatitis.

Endocrine, Respiratory & Anti-Infective Pharmacotherapy

1. Endocrine & Metabolic Agents

• Biguanides - Metformin (Glucophage):
  • First-line oral pharmacotherapy for Type 2 Diabetes Mellitus.
  • Mechanism: Decreases hepatic gluconeogenesis, reduces intestinal glucose absorption, and improves peripheral insulin sensitivity via AMP-activated protein kinase (AMPK) activation. Does not stimulate insulin release and therefore does not cause hypoglycemia when used as monotherapy.
  • Adverse Effects: Gastrointestinal distress (diarrhea, abdominal cramps, nausea, metallic taste), vitamin B12 deficiency with long-term therapy, rare lactic acidosis (contraindicated in severe renal failure with eGFR < 30 mL/min/1.73 m²).
  • Auxiliary Warning: Take with food or immediately after meals to reduce stomach upset; swallow extended-release tablets (Glumetza) whole.
• Sodium-Glucose Cotransporter 2 (SGLT2) Inhibitors:
  • Examples: Empagliflozin (Jardiance), dapagliflozin (Forxiga), canagliflozin (Invokana).
  • Mechanism: Inhibit SGLT2 in the renal proximal convoluted tubule, preventing glucose and sodium reabsorption, causing glucosuria and lowering blood glucose independent of insulin. Provide proven renal and cardiovascular protection (heart failure hospitalizations).
  • Adverse Effects: Genital mycotic infections (yeast infections), urinary tract infections, volume depletion/hypotension, rare euglycemic diabetic ketoacidosis (euDKA).
• Glucagon-Like Peptide-1 (GLP-1) Receptor Agonists:
  • Examples: Semaglutide (Ozempic [SC weekly], Rybelsus [oral daily], Wegovy [weight management]), dulaglutide (Trulicity), liraglutide (Victoza [diabetes], Saxenda [weight management]).
  • Mechanism: Incretin mimetics that stimulate glucose-dependent insulin secretion, suppress glucagon release, and delay gastric emptying, promoting satiety.
  • Administration & Storage: Injectable pens require cold-chain refrigeration (2°C to 8°C) before first use; once in-use, pens may remain at room temperature for specified durations (e.g., Ozempic room temp up to 56 days). Oral Rybelsus must be swallowed whole on an empty stomach upon waking with a sip of plain water (no more than 120 mL) at least 30 minutes before any food, other beverage, or other oral medications.
• Insulin Formulations:
  • Rapid-Acting Analogs: Insulin lispro (Humalog), insulin aspart (NovoRapid), insulin glulisine (Apidra). Onset: 10-15 minutes; peak: 1-2 hours; duration: 3-5 hours. Inject immediately (0 to 15 minutes) before or immediately after meals.
  • Short-Acting (Regular): Humulin R, Novolin ge Toronto. Onset: 30 minutes; inject 30 minutes before meals.
  • Intermediate-Acting: NPH (Humulin N, Novolin ge NPH). Cloudy suspension containing protamine; roll gently between palms (do not shake violently) before drawing up.
  • Long-Acting Basal Analogs: Insulin glargine (Lantus, Basaglar, Toujeo [concentrated 300 units/mL]), insulin detemir (Levemir), insulin degludec (Tresiba). Provide peakless 24-hour basal coverage. Do not mix glargine with any other insulin in the same syringe.
  • Storage: Unopened vials and pens are refrigerated (2°C to 8°C) and never frozen. In-use vials and pens are kept at room temperature for the period in the product monograph (commonly 28 days; some products are longer, such as insulin degludec at 56 days), which also avoids painful cold injections.
• Thyroid Replacement - Levothyroxine (Synthroid and generics):
  • Mechanism: Synthetic T4 hormone replacing endogenous thyroxine in hypothyroidism.
  • Narrow Therapeutic Index: Formulated in microgram strengths (e.g., 25 mcg up to 300 mcg); color-coded tablets.
  • Administration: Take once daily on an empty stomach with a full glass of water, at least 30 to 60 minutes before breakfast. Must be separated by at least 4 hours from calcium, iron, antacids, or cholestyramine supplements due to severe chelation and impaired absorption.

2. Respiratory Agents (Inhalers & Devices)

• Short-Acting Beta-2 Agonists (SABA): Salbutamol (Ventolin, Airomir). Rescue bronchodilator for acute bronchospasm. Common side effects: fine skeletal muscle tremor, tachycardia, palpitations, hypokalemia with overuse.
• Inhaled Corticosteroids (ICS): Fluticasone propionate (Flovent), budesonide (Pulmicort), ciclesonide (Alvesco). Daily maintenance anti-inflammatory therapy. Auxiliary label: Rinse mouth thoroughly with water and spit it out after each use to prevent oral candidiasis (thrush) and dysphonia (hoarseness).
• Long-Acting Beta-2 Agonist / Inhaled Corticosteroid Combinations (LABA/ICS): Salmeterol/fluticasone (Advair Diskus / Advair MDI), budesonide/formoterol (Symbicort Turbuhaler). Maintenance control in asthma and COPD.
• Long-Acting Muscarinic Antagonists (LAMA): Tiotropium (Spiriva HandiHaler [capsules for inhalation only, never swallowed], Spiriva Respimat). Bronchodilator for COPD.

3. Anti-Infective Agents

• Penicillins: Amoxicillin (Amoxil), amoxicillin-clavulanic acid (Clavulin). Beta-lactams that inhibit bacterial cell wall synthesis. Clavulanic acid is a beta-lactamase inhibitor overcoming bacterial enzymatic resistance. Common side effect: diarrhea (higher incidence with Clavulin). After reconstitution, follow the product monograph: amoxicillin-clavulanate (Clavulin) suspension is refrigerated and discarded after 10 days, and amoxicillin suspension is typically stable for 14 days (refrigeration preferred).
• Cephalosporins: Cephalexin (Keflex - 1st gen, skin/soft tissue), cefuroxime axetil (Ceftin - 2nd gen), cefixime (Suprax - 3rd gen), ceftriaxone (IV 3rd gen). Cross-reactivity with true penicillin allergies is low (~1-2%), but avoided in severe IgE-mediated anaphylactic penicillin allergies unless cleared by allergy specialist.
• Macrolides: Azithromycin (Zithromax), clarithromycin (Biaxin). Inhibit 50S ribosomal subunit. Common side effects: GI upset, abdominal cramping, QT interval prolongation. Clarithromycin is a potent CYP3A4 inhibitor with extensive drug interactions (statins, colchicine).
• Fluoroquinolones: Ciprofloxacin (Cipro), levofloxacin, moxifloxacin (Avelox). Inhibit DNA gyrase and topoisomerase IV. High-risk class associated with tendinitis and tendon rupture (Achilles tendon), peripheral neuropathy, CNS toxicities, and QT prolongation. Polyvalent cations (calcium, magnesium, aluminum, iron) chelate fluoroquinolones—separate administration by at least 2 hours before or 4 to 6 hours after.
• Antifungals: Fluconazole (Diflucan - single-dose 150 mg oral for vulvovaginal candidiasis; potent CYP2C9 inhibitor interacting with warfarin and phenytoin), terbinafine (Lamisil - oral onychomycosis, requires baseline liver enzymes).
• Antivirals: Valacyclovir (Valtrex - prodrug of acyclovir with enhanced oral bioavailability for herpes simplex and zoster), oseltamivir (Tamiflu - influenza neuraminidase inhibitor, most effective if initiated within 48 hours of symptom onset).

4. Gastrointestinal Agents

• Proton Pump Inhibitors (PPIs): Pantoprazole (Pantoloc), omeprazole (Losec), lansoprazole (Prevacid), esomeprazole (Nexium). Irreversibly bind to and inactivate the H+/K+ ATPase pump in gastric parietal cells. Take 30 to 60 minutes prior to the first meal of the day. Tablets must be swallowed whole without chewing or crushing to preserve enteric coating. Long-term risks include hypomagnesemia, impaired vitamin B12 absorption, osteoporosis-related fractures, and Clostridioides difficile colitis.
• Histamine-2 Receptor Antagonists (H2RAs): Famotidine. Competitively block H2 receptors on parietal cells. Rapid onset for episodic heartburn, available over-the-counter and by prescription.
• Antiemetics: Dimenhydrinate (Gravol - H1 antihistamine with anticholinergic properties; causes sedation, dry mouth, urinary retention); Ondansetron (Zofran - 5-HT3 receptor antagonist for chemotherapy-induced, radiation, and postoperative nausea/vomiting; causes constipation and headache); Metoclopramide (Maxeran - prokinetic dopamine D2 antagonist; risk of extrapyramidal symptoms and tardive dyskinesia).

Canadian Drug Classes Master Reference Table

The following master reference table summarizes key Canadian drug classes, mechanisms, representative agents, and critical dispensing precautions: