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Pharmacology: Drug Classes, Routes, Calculations, and Vaccines
Pharmacology on the CCMA exam is practical rather than 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. Drug name endings are your fastest route to identifying a class you have never seen before.
Drug classifications by body system
Most exam questions describe a drug by its class and ask what it treats, or name a drug and ask which class it belongs to. Learning the common suffixes lets you classify an unfamiliar generic name on sight. Generic names are lowercase and universal while brand names are capitalized and owned by a manufacturer.
Cardiovascular agents
Antihypertensives include ACE inhibitors ending in -pril, angiotensin receptor blockers ending in -sartan, beta blockers ending in -olol, and calcium channel blockers often ending in -dipine. Statins ending in -statin lower cholesterol and anticoagulants reduce clot formation.
Respiratory agents
Bronchodilators such as short-acting beta agonists relieve acute bronchospasm, inhaled corticosteroids prevent airway inflammation over time, and antihistamines, decongestants, antitussives, and expectorants treat allergy and cough symptoms.
Nervous system agents
Analgesics relieve pain, opioids act centrally and carry addiction risk, benzodiazepines ending in -pam or -lam reduce anxiety, SSRIs treat depression, anticonvulsants control seizures, and anesthetics produce local or general loss of sensation.
Endocrine agents
Insulin and oral agents such as metformin lower blood glucose, levothyroxine replaces thyroid hormone in hypothyroidism, and corticosteroids suppress inflammation and immune response.
Gastrointestinal agents
Antacids neutralize existing stomach acid, proton pump inhibitors ending in -prazole reduce acid production, antiemetics control nausea and vomiting, and laxatives and antidiarrheals regulate bowel movement.
Anti-infectives
Antibiotics such as penicillins ending in -cillin, macrolides ending in -mycin or -thromycin, and fluoroquinolones ending in -floxacin treat bacterial infection, while antivirals treat viral infection and antifungals often end in -azole. Antibiotics have no effect on viruses.
Routes of administration and prescription abbreviations
The route determines how fast a drug takes effect, how much reaches the bloodstream, and what technique you must use. Enteral routes pass through the gastrointestinal tract while parenteral routes bypass it entirely. Abbreviations save time on a prescription but a misread abbreviation is a classic source of serious medication error.
Enteral routes
Oral is the most common and convenient but the slowest, sublingual under the tongue and buccal against the cheek absorb rapidly through mucosa and bypass the liver, and rectal is useful when the patient is vomiting or unconscious.
Parenteral routes
Intradermal, subcutaneous, intramuscular, and intravenous all bypass the digestive tract. Intravenous produces the fastest onset because the drug enters circulation directly, and intradermal is the slowest to absorb.
Topical and mucosal routes
Transdermal patches deliver a steady dose through the skin, ophthalmic drops go into the lower conjunctival sac rather than directly on the cornea, and inhaled medication acts directly on the airways.
Otic administration by age
For an adult, pull the pinna up and back before instilling ear drops. For a child under about three years, pull the pinna down and back, because the ear canal is angled differently.
Frequency and timing abbreviations
BID is twice daily, TID is three times daily, QID is four times daily, q4h is every four hours, ac is before meals, pc is after meals, hs is at bedtime, PRN is as needed, and stat means immediately.
Dangerous abbreviations to avoid
Do not use U for units, IU for international units, QD or QOD for daily and every other day, or a trailing zero such as 1.0 mg. Always use a leading zero, writing 0.5 mg rather than .5 mg.
The Joint Commission Do Not Use ListDosage calculation
Dosage math on the exam is arithmetic, not algebra, but a misplaced decimal point is a tenfold error. Convert all values to the same unit of measure before you calculate anything, and check that your answer is a reasonable volume for the route. If the answer would require 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 that dose comes in. For 500 mg desired from a 250 mg per tablet supply, 500 divided by 250 times 1 tablet equals 2 tablets.
Metric conversions
One gram equals 1000 milligrams, one milligram equals 1000 micrograms, one liter equals 1000 milliliters, and one kilogram equals 1000 grams. Moving from a larger to a smaller unit multiplies, and the reverse divides.
Household and weight conversions
One teaspoon is about 5 mL, one tablespoon is about 15 mL, one fluid ounce is about 30 mL, and one kilogram equals 2.2 pounds.
Weight-based pediatric dosing
Pediatric orders are commonly written as milligrams per kilogram per day. Convert the child's weight from pounds to kilograms first by dividing by 2.2, then multiply by the ordered milligrams per kilogram.
Body surface area dosing
Body surface area, expressed in square meters and derived from height and weight, is used for chemotherapy and some pediatric drugs because it estimates metabolic capacity more accurately than weight alone.
High-alert medications need a second check
Insulin, heparin, opioids, and concentrated electrolytes cause disproportionate harm when given in error, so independent double checks and standardized concentrations are standard safeguards.
ISMP List of High-Alert MedicationsAdverse reactions, allergies, and interactions
Recognizing the difference between an expected side effect and 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.
Side effect versus adverse reaction versus allergy
A side effect is a known, usually tolerable secondary effect, an adverse drug reaction is harmful and unintended, an allergic reaction is immune-mediated and can escalate, and an idiosyncratic reaction is an unexpected individual response.
Recognizing anaphylaxis
Look for 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 the first-line treatment
For anaphylaxis, epinephrine is given by intramuscular injection into the mid-outer thigh, the vastus lateralis, because that site provides the fastest absorption. Antihistamines are adjuncts and never a substitute.
Post-vaccination observation
Observe patients for 15 minutes after vaccination and keep them seated or lying down, because syncope and the rare immediate hypersensitivity reaction usually occur within that window.
CDCReporting adverse events
Serious adverse events involving drugs and devices are reported to the FDA through MedWatch, while adverse events following immunization are reported to the Vaccine Adverse Event Reporting System.
FDA MedWatch and VAERSCommon interactions to know
Grapefruit juice raises blood 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.
Controlled substances and immunizations
Controlled substances are governed by federal schedules that determine storage, prescribing, refills, and recordkeeping, and errors here are regulatory violations rather than simple mistakes. Vaccines have their own parallel rules for storage temperature, documentation, and patient information. Both areas are heavily tested because both carry legal consequences.
The five schedules
Schedule I has no accepted medical use, Schedule II has high abuse potential with accepted use such as oxycodone and methylphenidate, Schedule III includes moderate potential such as buprenorphine and anabolic steroids, Schedule IV includes benzodiazepines and tramadol, and Schedule V includes low-dose codeine preparations.
Controlled Substances ActPrescription limits
Schedule II prescriptions cannot be refilled and require a new prescription each time, while Schedule III and IV prescriptions may be refilled up to five times within six months of the date written.
DEA 21 CFR Part 1306Storage and inventory
Controlled substances must be stored in a securely locked, substantially constructed cabinet, a biennial inventory must be taken, and required records must be kept for at least two years and available for inspection.
DEA 21 CFR Part 1304Vaccine storage temperatures
Refrigerated vaccines are stored at 36 to 46 degrees F (2 to 8 degrees C) and frozen varicella-containing vaccines at the manufacturer's specified freezer range. Temperatures must be monitored and logged with a calibrated digital data logger.
CDC Vaccine Storage and Handling ToolkitVaccine Information Statements
The current Vaccine Information Statement must be given to the patient or parent before every dose of a covered vaccine, and the chart must record the VIS edition date and the date it was provided.
National Childhood Vaccine Injury ActDocumenting an immunization
Record 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.
CDC ACIP Immunization SchedulesKiểm tra kiến thức của bạn
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