DHA Pharmacist Exam flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Therapeutic index

Ratio of the dose producing toxicity to the dose producing therapeutic effect; a narrow index, as with digoxin, warfarin and lithium, requires therapeutic drug monitoring.

Zero-order kinetics

Elimination of a constant amount of drug per unit time because metabolic enzymes are saturated; phenytoin, ethanol and high-dose salicylates behave this way, so half-life lengthens as dose rises.

Metformin mechanism

Biguanide that reduces hepatic gluconeogenesis and improves insulin sensitivity; first-line therapy for type 2 diabetes, it does not cause hypoglycemia alone but carries lactic acidosis risk in renal impairment.

ACE inhibitor cough

Persistent dry cough caused by bradykinin accumulation during angiotensin-converting enzyme inhibition; it usually resolves after switching to an angiotensin receptor blocker.

Cockcroft-Gault equation

Estimates creatinine clearance as [(140 − age) × weight] divided by (72 × serum creatinine), multiplied by 0.85 for females; used to adjust renally cleared drug doses.

High-alert medications

Drugs carrying heightened risk of harmful error, including insulin, heparin, opioids, concentrated electrolytes, neuromuscular blockers and chemotherapy; they require independent double-checks and standardized storage.

Proportion of days covered

Adherence metric calculated as days covered by medication supply divided by days in the measurement period; a value of 80% or more generally defines good adherence.

Medication reconciliation

Structured comparison of a patient's current medication list with newly ordered medicines at admission, transfer and discharge to prevent omissions, duplications and dosing errors.

Bioavailability formula

F equals (AUC oral ÷ AUC intravenous) × (dose intravenous ÷ dose oral); intravenous bioavailability is defined as 1, and oral values are reduced by first-pass metabolism.

Noyes-Whitney equation

States that dissolution rate is proportional to surface area, diffusion coefficient and drug solubility, and inversely proportional to diffusion layer thickness; micronization and salt formation increase dissolution.

Bioequivalence criteria

Two products are bioequivalent when the 90% confidence interval of the geometric mean ratios for AUC and Cmax falls entirely within the 80% to 125% range.

Volume of distribution

Apparent volume calculated as dose divided by plasma concentration at time zero; large values indicate extensive tissue distribution, while small values indicate confinement to plasma.

Enalapril prodrug activation

Enalapril is an inactive ester hydrolysed in the liver to enalaprilat, which inhibits angiotensin-converting enzyme; the prodrug improves oral absorption of the polar active acid.

Lipinski rule of five

Drug-likeness guideline: molecular weight 500 or less, logP 5 or less, hydrogen bond donors 5 or less and acceptors 10 or less; violations predict poor oral absorption.

Henderson-Hasselbalch equation

pH equals pKa plus the log of the ratio of unprotonated to protonated species; it predicts the ionized fraction of a weak acid or base at a given pH.

Vinca alkaloid source

Vincristine and vinblastine are alkaloids extracted from the Madagascar periwinkle, Catharanthus roseus; they bind tubulin and arrest mitosis in metaphase.

Minimum inhibitory concentration

Lowest antimicrobial concentration that prevents visible growth of a standardized bacterial inoculum after overnight incubation; interpreted against breakpoints to classify susceptibility.

Gram-negative outer membrane

Lipid bilayer containing lipopolysaccharide that lies outside a thin peptidoglycan layer; it is a permeability barrier and releases endotoxin capable of triggering septic shock.

Autoclave standard cycle

Steam sterilization at 121 degrees Celsius and 15 psi for at least 15 minutes, monitored with biological indicators such as Geobacillus stearothermophilus spores.

ISO class 5 environment

Air cleanliness standard permitting no more than 3,520 particles of 0.5 micrometre or larger per cubic metre; required for the direct compounding area in sterile compounding.

Spaulding classification

Divides devices into critical (enter sterile tissue, require sterilization), semicritical (contact mucous membranes, need high-level disinfection) and noncritical (intact skin, low-level disinfection).

Depyrogenation

Destruction or removal of pyrogens such as endotoxin; dry heat at 250 degrees Celsius for 30 minutes is standard, and 0.22 micrometre filtration does not reliably remove endotoxin.

Informed consent elements

Requires disclosure of diagnosis, nature and purpose of treatment, risks, benefits and alternatives, plus a voluntary decision made by a patient with capacity and without coercion.

Four ethical principles

Autonomy respects patient choice, beneficence acts for patient benefit, nonmaleficence avoids harm, and justice ensures fair distribution of resources; together they guide clinical decisions.

Pharmacovigilance definition

Science and activities relating to detection, assessment, understanding and prevention of adverse effects or other drug-related problems, usually coordinated by national regulatory authorities.

Generic substitution condition

Substitution is permitted only when the product is legally interchangeable, contains the same active moiety, strength and dosage form, and local regulations and prescriber requirements are satisfied.

Tertiary literature

Summarized, indexed references such as textbooks, compendia and review databases including Martindale, AHFS and Micromedex; convenient for background but may lag current evidence.

PICO framework

Structured clinical question format describing Patient or population, Intervention, Comparator and Outcome; used to build searchable, answerable drug information queries.

Naranjo scale

Ten-item questionnaire scoring temporal plausibility, dechallenge, rechallenge, alternative causes and prior reports to classify adverse drug reactions as definite, probable, possible or doubtful.

Number needed to treat

Reciprocal of the absolute risk reduction (1 divided by ARR); the number of patients who must be treated for one additional patient to gain benefit.

Sensitivity definition

Proportion of people with disease who test positive, calculated as true positives divided by true positives plus false negatives; high sensitivity makes a test useful for ruling out disease.

Intention-to-treat analysis

Analyses all randomized participants within their assigned groups regardless of adherence or crossover; this preserves randomization and prevents attrition bias.