FPGEE cheat sheet

Henderson–Hasselbalch: for a weak acid, pH = pKa + log([A−]/[HA]); for a weak base, pH = pKa + log([B]/[BH+]).

Volume of distribution Vd = amount of drug in body / plasma concentration; loading dose = (Vd × target concentration) / F.

Clearance CL = dose / AUC; elimination half-life t1/2 = 0.693 × Vd / CL; steady state is reached in about 4–5 half-lives.

Oral bioavailability F = (AUC_oral × dose_IV) / (AUC_IV × dose_oral); first-pass metabolism lowers F for orally administered drugs.

Zero-order elimination removes a constant amount per unit time; half-life increases as concentration rises (phenytoin, ethanol, high-dose aspirin).

MIC is the lowest antimicrobial concentration that inhibits visible growth; PK/PD indices include time above MIC (beta-lactams), AUC/MIC (vancomycin), and Cmax/MIC (aminoglycosides).

Gram-positive bacteria have a thick peptidoglycan layer; gram-negative bacteria have an outer membrane; beta-lactams inhibit penicillin-binding protein transpeptidation.

IgM is the first antibody produced in a primary response, IgG is the most abundant serum immunoglobulin, IgA predominates in mucosa, and IgE mediates mast-cell degranulation.

Bacterial protein synthesis inhibitors bind the 30S subunit (aminoglycosides, tetracyclines) or the 50S subunit (macrolides, clindamycin, chloramphenicol).

Potency is reflected by EC50 (lower EC50 = greater potency); efficacy is reflected by Emax.

Competitive antagonists shift the dose-response curve right and increase EC50 without changing Emax; noncompetitive antagonists reduce Emax.

Therapeutic index TI = TD50 / ED50; a larger TI indicates a wider margin between toxic and effective doses.

Phase I metabolism uses oxidation, reduction, and hydrolysis, often by CYP450; phase II metabolism conjugates drugs via glucuronidation, sulfation, acetylation, or glutathione.

CYP3A4 inhibitors include ketoconazole, clarithromycin, ritonavir, and grapefruit; inducers include rifampin, carbamazepine, phenytoin, and St. John's wort.

Prodrugs are inactive until metabolized in vivo; examples include enalapril to enalaprilat and codeine to morphine.

Antidotes: N-acetylcysteine for acetaminophen, naloxone for opioids, flumazenil for benzodiazepines, fomepizole for methanol or ethylene glycol, deferoxamine for iron, pralidoxime for organophosphates.

For narrow-therapeutic-index drugs, small dose increases can produce large level increases when elimination is saturated (phenytoin, theophylline, lithium).

Enantiomers can differ in activity and clearance; examples include S-warfarin (more potent) and S-omeprazole (more active).

Cockcroft–Gault creatinine clearance = [(140 − age) × weight kg] / [72 × serum creatinine mg/dL], multiplied by 0.85 for women.

Warfarin INR target is 2.0–3.0 for most atrial fibrillation and venous thromboembolism indications; mechanical mitral valves often target 2.5–3.5.

For serious MRSA infections, vancomycin AUC24/MIC target is 400–600; AUC-guided monitoring is preferred over trough-only monitoring.

Metformin is first-line for type 2 diabetes unless contraindicated; avoid initiation when eGFR is below 45 and contraindicate below 30 mL/min/1.73 m².

HFrEF guideline-directed therapy combines an ARNI, ACE inhibitor, or ARB with a beta-blocker, mineralocorticoid receptor antagonist, and SGLT2 inhibitor.

CHA2DS2-VASc estimates stroke risk in nonvalvular atrial fibrillation; higher scores support anticoagulation after bleeding-risk assessment.

Beers Criteria identify potentially inappropriate medications for adults aged 65 and older, including benzodiazepines, anticholinergics, and certain NSAIDs.

High-intensity statin therapy (atorvastatin 40–80 mg or rosuvastatin 20–40 mg) is used for established atherosclerotic cardiovascular disease.

HbA1c target is below 7% for most nonpregnant adults with diabetes, individualized for hypoglycemia risk, comorbidity, and life expectancy.

Incremental cost-effectiveness ratio ICER = (Cost_A − Cost_B) / (Effect_A − Effect_B); compare with a willingness-to-pay threshold.

Cost-minimization analysis assumes equivalent outcomes and compares only costs; cost-benefit analysis values outcomes in monetary units; cost-utility analysis uses QALYs.

QALY = years of life × utility weight, where 0 represents death and 1 represents perfect health.

Future costs and health outcomes are discounted, commonly at 3% per year, in economic evaluations.

Sensitivity analysis varies model inputs to test whether economic conclusions remain robust under uncertainty.

Transtheoretical model stages are precontemplation, contemplation, preparation, action, and maintenance; interventions are matched to stage.

ABC inventory analysis classifies items by annual dollar value; class A items are roughly 20% of items but about 80% of value and require tight control.

Health belief model constructs include perceived susceptibility, perceived severity, perceived benefits, perceived barriers, and cues to action.

NCPDP and HL7 are interoperability standards used for pharmacy claims, e-prescribing, and health information exchange.

The Food, Drug, and Cosmetic Act of 1938 required premarket safety evidence; the Durham-Humphrey Amendment of 1951 created prescription versus over-the-counter status.

The Kefauver-Harris Amendment of 1962 required proof of efficacy and informed consent for clinical investigation.

The Controlled Substances Act of 1970 created schedules I–V based on abuse potential and accepted medical use, with DEA registration and recordkeeping.

Schedule II prescriptions cannot be refilled; emergency oral Schedule II prescriptions require written or electronic follow-up within seven days.

OBRA-90 requires Medicaid pharmacists to offer counseling and maintain patient records, supporting prospective drug utilization review.

HIPAA Privacy Rule protects protected health information and applies the minimum-necessary standard to disclosures.

USP <797> sets sterile compounding standards; USP <800> sets handling standards for hazardous drugs.

503A compounding pharmacies compound for individual prescriptions; 503B outsourcing facilities follow cGMP and adverse-event reporting requirements.

The Drug Supply Chain Security Act requires product tracing, verification, and serialization for prescription drugs.