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Pharmacology on the CCMA exam is practical, not theoretical: recognize what a drug class does, know how each route works, calculate a dose correctly, spot an adverse reaction, and follow the rules for controlled substances and vaccines. Your fastest tool for an unfamiliar drug is its name ending — the suffix usually reveals the class.

5.1 Drug Classifications by Body System

Most questions describe a drug by its class and ask what it treats, or name a drug and ask its class. Learning common suffixes lets you classify a generic name you have never seen. Generic names are lowercase and universal; brand names are capitalized and owned by a manufacturer.

• Cardiovascular: ACE inhibitors end in -pril (lisinopril); ARBs end in -sartan (losartan); beta blockers end in -olol (metoprolol); calcium channel blockers often end in -dipine (amlodipine); statins end in -statin and lower cholesterol; anticoagulants (warfarin) reduce clotting; loop diuretics such as furosemide increase urine output.
• Respiratory: short-acting beta agonists such as albuterol are fast bronchodilators; inhaled corticosteroids prevent airway inflammation over time; antihistamines, decongestants, antitussives, and expectorants treat allergy and cough.
• Nervous system: analgesics relieve pain; opioids act centrally and carry addiction risk; benzodiazepines end in -pam/-lam and reduce anxiety; SSRIs treat depression; anticonvulsants control seizures.
• Endocrine: insulin and oral agents such as metformin lower blood glucose; levothyroxine replaces thyroid hormone; corticosteroids suppress inflammation.
• Gastrointestinal: antacids neutralize acid; proton pump inhibitors end in -prazole and reduce acid production; antiemetics control nausea; laxatives and antidiarrheals regulate bowel movement.
• Anti-infectives: penicillins end in -cillin; macrolides in -mycin/-thromycin; fluoroquinolones in -floxacin; antifungals often in -azole. Antibiotics have no effect on viruses.

5.2 Routes of Administration and Prescription Abbreviations

The route determines how fast a drug acts, how much reaches the blood, and what technique you use. Enteral routes pass through the GI tract; parenteral routes bypass it.

• Enteral: oral (PO) is most common but slowest; sublingual (under the tongue, e.g., nitroglycerin) and buccal absorb rapidly through mucosa and bypass the liver; rectal is useful when the patient is vomiting or unconscious.
• Parenteral: intradermal, subcutaneous, intramuscular, and intravenous (IV). IV has the fastest onset because the drug enters circulation directly; intradermal is the slowest to absorb.
• Topical/mucosal: transdermal patches give a steady dose through the skin; ophthalmic drops go into the lower conjunctival sac, not on the cornea; inhaled medication acts on the airways.
• Otic (ear) by age: pull the pinna up and back for an adult; down and back for a child under about three.

Timing abbreviations: BID = twice daily, TID = three times daily, QID = four times daily, q4h = every four hours, ac = before meals, pc = after meals, hs = at bedtime, PRN = as needed, stat = immediately.

Dangerous abbreviations to avoid (The Joint Commission "Do Not Use" list): do not use U for units, IU for international units, QD/QOD for daily/every other day, or a trailing zero (write 1 mg, not 1.0 mg). Always use a leading zero — 0.5 mg, never .5 mg — because a missed decimal point is a tenfold error.

5.3 Dosage Calculation

Dosage math is arithmetic, not algebra, but a misplaced decimal is a tenfold error. Convert all values to the same unit first, then check that the answer is a reasonable volume for the route — if it would take ten tablets or 8 mL in a deltoid, you made a mistake.

Desired over Have. Divide the desired dose by the dose on hand and multiply by the quantity it comes in:

$$\text{Amount to give} = \frac{\text{Desired}}{\text{Have}} \times \text{Quantity}$$

For 500 mg desired from a 250 mg/tablet supply: 500 ÷ 250 × 1 tablet = 2 tablets. For a 250 mg/mL vial: 500 ÷ 250 = 2 mL.

Metric conversions: 1 g = 1000 mg, 1 mg = 1000 mcg, 1 L = 1000 mL, 1 kg = 1000 g. Larger to smaller multiplies; smaller to larger divides.

Household/weight: 1 tsp ≈ 5 mL, 1 tbsp ≈ 15 mL, 1 fl oz ≈ 30 mL, 1 kg = 2.2 lb.

Weight-based pediatric dosing is written as mg/kg. Convert pounds to kilograms first (÷ 2.2), then multiply by the ordered mg/kg. A 44-lb child at 10 mg/kg: 44 ÷ 2.2 = 20 kg; 20 × 10 = 200 mg. Forgetting to convert and using 44 gives 440 mg — a dangerous double dose.

Body surface area (BSA), in square meters from height and weight, is used for chemotherapy and some pediatric drugs. And high-alert medications — insulin, heparin, opioids, concentrated electrolytes — cause disproportionate harm in error, so an independent double check and standardized concentrations are standard safeguards (ISMP High-Alert list).

5.4 Adverse Reactions, Allergies, and Interactions

Telling an expected side effect from a true emergency is a core safety skill. Any reaction involving the airway, breathing, or circulation is treated as anaphylaxis until proven otherwise. Document every reaction with the drug name, the reaction described, and the time it began.

Know the definitions: a side effect is a known, usually tolerable secondary effect (mild drowsiness); an adverse drug reaction is harmful and unintended; an allergic reaction is immune-mediated and can escalate; an idiosyncratic reaction is an unexpected individual response.

Recognize anaphylaxis: hives, swelling of the lips, tongue, or throat, wheezing or stridor, difficulty breathing, hypotension, rapid weak pulse, and a sense of impending doom. Activate emergency services immediately and notify the provider. Epinephrine is first-line, given IM into the mid-outer thigh (vastus lateralis) for the fastest absorption; antihistamines are adjuncts, never a substitute.

Two documentation-and-reporting rules: observe patients for 15 minutes after vaccination (seated or lying down), because syncope and immediate hypersensitivity usually occur in that window; and report serious drug/device events to the FDA through MedWatch, and adverse events after immunization to VAERS. A reported allergy such as "penicillin gives me a rash" goes in the allergy field, flagged prominently, with the provider informed — never buried in a free-text note or dismissed. Common interactions to know: grapefruit juice raises levels of certain statins and calcium channel blockers; warfarin interacts with vitamin-K-rich foods and with NSAIDs; and antibiotics can reduce the effectiveness of oral contraceptives.

5.5 Controlled Substances and Immunizations

Controlled substances are governed by federal schedules that determine storage, prescribing, refills, and recordkeeping; errors here are regulatory violations, not simple mistakes. Vaccines have their own parallel rules for storage, documentation, and patient information.

The five schedules (Controlled Substances Act):

• Schedule I — no accepted medical use (heroin, LSD).
• Schedule II — high abuse potential with accepted use (oxycodone, methylphenidate). No refills — a new prescription each time.
• Schedule III — moderate potential (buprenorphine, anabolic steroids).
• Schedule IV — benzodiazepines, tramadol.
• Schedule V — low-dose codeine preparations.

Prescription limits: Schedule II cannot be refilled; Schedule III and IV may be refilled up to five times within six months of the date written (DEA 21 CFR Part 1306). Storage and inventory: controlled substances are kept in a securely locked, substantially constructed cabinet, a biennial (every two years) inventory is taken, and records are kept at least two years for inspection (DEA 21 CFR Part 1304).

Vaccines: refrigerated vaccines are stored at 36–46°F (2–8°C) in the center of a dedicated unit — not the door — with temperatures monitored and logged using a calibrated digital data logger; frozen varicella-containing vaccines go in the manufacturer's freezer range. The current Vaccine Information Statement (VIS) must be given before every dose of a covered vaccine, and the chart must record the VIS edition date and the date provided (National Childhood Vaccine Injury Act). Document an immunization with the vaccine name, manufacturer, lot number, expiration date, dose, route, anatomic site, date given, and the name and title of the person administering it. The recommended schedules are published annually by CDC/ACIP.

Key Numbers & Facts — Chapter 5 (memorize cold)

Clinical Walkthrough — A Pediatric Dose and a Reaction

A provider orders a medication at 10 mg/kg for a child who weighs 44 pounds, supplied as 200 mg per 5 mL. First, convert: 44 ÷ 2.2 = 20 kg. The dose is 20 × 10 = 200 mg. Now the volume: using Desired/Have, 200 mg ÷ 200 mg × 5 mL = 5 mL. Note how skipping the pound-to-kilogram conversion would have you calculating from 44 "kg" and pushing a 440 mg dose — a classic, dangerous trap the exam sets on purpose. You give the dose, then observe — and minutes later the child develops hives, lip swelling, and wheezing. That is the airway-breathing-circulation pattern, so you treat it as anaphylaxis: stay with the patient, call for the provider and emergency help, and prepare to assist with epinephrine per protocol. Water, a cold pack, or a follow-up next week are all distractors that waste the minutes that matter. Convert before you calculate, and treat any airway reaction as anaphylaxis until proven otherwise — those two reflexes carry most of this domain.

Exam Traps — Chapter 5

• The pounds-as-kilograms trap. Always convert lb ÷ 2.2 before a weight-based dose. Using the pound number directly roughly doubles the dose.
• The trailing-zero trap. Write 1 mg, not 1.0 mg, and 0.5 mg, not .5 mg. A missed decimal is a tenfold error, which is why the "Do Not Use" list bans it.
• The Schedule II refill trap. Schedule II drugs cannot be refilled — each fill needs a new prescription. Only III–V refill (up to 5×/6 months).
• The antibiotic-for-a-virus trap. Antibiotics do nothing to viruses; an option treating a viral illness with an antibiotic is wrong.
• The antihistamine-for-anaphylaxis trap. First-line for anaphylaxis is epinephrine; antihistamines are adjuncts, never the primary treatment.
• The fridge-door trap. Store vaccines in the center of the unit at 36–46°F, never on the door, and never at room temperature.
• The sublingual "chew and swallow" trap. A sublingual tablet is meant to dissolve under the tongue; chewing or swallowing defeats the rapid, liver-bypassing route.