NAPLEX cheat sheet

ACC/AHA blood pressure staging: normal <120/80 mm Hg; stage 1 is 130-139/80-89 mm Hg; stage 2 is ≥140/90 mm Hg.

First-line antihypertensive classes per 2017 ACC/AHA are thiazide-type diuretics, ACE inhibitors, ARBs, and dihydropyridine calcium channel blockers.

Metformin is first-line for type 2 diabetes; do not initiate at eGFR <45 mL/min/1.73 m² and contraindicate at eGFR <30 mL/min/1.73 m².

High-intensity statin therapy (atorvastatin 40-80 mg or rosuvastatin 20-40 mg) lowers LDL-C by ≥50% and is indicated for clinical ASCVD.

HFrEF quadruple therapy: ARNI (or ACE inhibitor/ARB) + evidence-based beta-blocker (bisoprolol, carvedilol, metoprolol succinate) + mineralocorticoid receptor antagonist + SGLT2 inhibitor.

Warfarin INR targets: 2.0-3.0 for atrial fibrillation and VTE; 2.5-3.5 for mechanical mitral valves and antiphospholipid syndrome.

Serious MRSA infections: target vancomycin AUC24/MIC of 400-600 mg·h/L; trough-only monitoring is no longer the preferred approach.

Therapeutic ranges to recall: digoxin in heart failure 0.5-0.9 ng/mL; lithium maintenance 0.6-1.2 mEq/L; phenytoin total 10-20 mcg/mL.

Convulsive status epilepticus: benzodiazepine first (IV lorazepam or IM midazolam), then fosphenytoin, levetiracetam, or valproate.

Bioequivalence: the 90% confidence interval for the test/reference ratio of AUC and Cmax must fall within 80%-125%.

Volume of distribution = amount of drug in the body ÷ plasma concentration; a large Vd reflects extensive tissue distribution and limits removal by hemodialysis.

Loading dose = (Vd × target plasma concentration) ÷ bioavailability (F); maintenance dosing rate = (CL × Css × τ) ÷ F.

Approximately 4-5 elimination half-lives are required to reach steady state, and the same interval applies to washout after discontinuation.

Zero-order (saturable) kinetics occur with phenytoin, ethanol, and high-dose salicylates: a constant amount is eliminated per unit time regardless of concentration.

Prodrugs requiring activation include clopidogrel (CYP2C19), codeine (CYP2D6), valacyclovir (to acyclovir), and enalapril (to enalaprilat).

Pharmacogenomic screens: HLA-B5701 before abacavir, HLA-B1502 before carbamazepine in patients of Asian ancestry, and TPMT/NUDT15 before thiopurines.

Narrow therapeutic index drugs (warfarin, digoxin, lithium, phenytoin, cyclosporine, tacrolimus) warrant therapeutic drug monitoring and careful product substitution.

Cockcroft-Gault: CrCl (mL/min) = [(140 − age) × weight kg] ÷ (72 × SCr mg/dL); multiply by 0.85 for female patients.

Dilution formula: C1 × V1 = C2 × V2. Alligation: parts of each component = absolute difference between its strength and the desired strength.

Percent strength conventions: % w/v = g per 100 mL, % v/v = mL per 100 mL, % w/w = g per 100 g; ratio strength 1:1000 equals 0.1% w/v.

Milliequivalents: mEq = (mg × valence) ÷ molecular weight; used for electrolyte orders such as KCl and sodium bicarbonate.

Sodium chloride equivalent method: total NaCl needed = (weight of drug × E-value) + NaCl added, to reach 0.9 g per 100 mL of final solution.

IV drip rate (gtt/min) = (volume in mL × drop factor in gtt/mL) ÷ time in minutes.

USP <795> default nonsterile BUDs: 180 days for nonaqueous dosage forms, 14 days refrigerated for water-containing oral liquids, 30 days for water-containing topical preparations.

Common conversions: 1 fl oz = 30 mL, 1 tsp = 5 mL, 1 tbsp = 15 mL, 1 grain = 65 mg, 1 kg = 2.2 lb.

Body surface area by Mosteller = √[(height cm × weight kg) ÷ 3600]; used for chemotherapy and pediatric dosing.

Schedule II purchases require DEA Form 222 or its electronic equivalent (CSOS); each line item may be ordered from only one supplier.

Schedule III-V prescriptions may be refilled up to five times within six months of the issue date; Schedule II prescriptions permit no refills.

Schedule II partial filling is allowed within 72 hours of the original date, or up to 30 days for patients in long-term care or with terminal illness.

Emergency oral Schedule II orders require delivery of a written or electronic prescription within seven days.

A complete controlled substance inventory is required every two years (biennial), and required records are retained for at least two years.

Stock rotation follows FEFO (first-expired, first-out) rather than simple FIFO because shelf-life varies by lot and product.

Expired or unusable controlled substances are transferred to a reverse distributor; DEA Form 41 documents destruction.

Inventory turnover = cost of goods sold ÷ average inventory value; low turnover flags overstock and expiration risk.

DSCSA requires interoperable, serialized product tracing; small dispensers received an exemption from certain requirements through November 27, 2026.

Teach-back confirms comprehension by asking the patient to restate instructions in their own words; closed yes/no questions do not verify understanding.

Health literacy universal precautions: assume limited literacy for every patient and use plain language at roughly a 5th-6th grade reading level.

Eye drops: separate multiple drops by about 5 minutes and perform punctal occlusion for 1-2 minutes to reduce systemic absorption.

Inhaled corticosteroids require mouth rinsing after use; a valved holding chamber improves lung deposition and reduces oropharyngeal side effects.

Most in-use insulin pens and vials are stable for 28 days at room temperature; unopened stock is refrigerated at 2-8 °C and never frozen.

Sublingual nitroglycerin: patient sits down, takes one tablet, and calls 911 if chest pain persists or worsens 5 minutes after the first dose.

Motivational interviewing microskills are summarized as OARS: open questions, affirmations, reflections, and summaries.

SBAR (Situation, Background, Assessment, Recommendation) structures pharmacist-to-prescriber communication about drug therapy problems.

Core elements of medication therapy management: medication therapy review, personal medication record, medication action plan, intervention/referral, and documentation with follow-up.

OBRA '90 requires Medicaid-participating pharmacies to perform prospective drug utilization review and to offer counseling to patients or caregivers.

Combat Methamphetamine Epidemic Act limits: pseudoephedrine sales of 3.6 g per day and 9 g per 30 days per purchaser, with photo ID and a written or electronic logbook.

HIPAA minimum necessary standard limits uses and disclosures of protected health information; breach notification is generally due within 60 days of discovery.

DEA registrations are valid for three years and must be renewed prior to expiration to continue handling controlled substances.

FDA recall classes: Class I = reasonable probability of serious adverse health consequences or death; Class II = temporary or reversible harm; Class III = unlikely to cause harm.

Marketing exclusivity periods: 5 years for a new chemical entity, 7 years for orphan drugs, 6 months pediatric exclusivity, and 180 days for the first generic challenger.

The Pregnancy and Lactation Labeling Rule (effective 2015) replaced pregnancy categories A, B, C, D, and X with narrative risk summaries.

USP <800> governs hazardous drug handling, including containment, closed system transfer devices, negative-pressure rooms, and personal protective equipment.

Drug recalls, label changes, and serious adverse events are reported to FDA MedWatch; the NDC is formatted as 5-digit labeler, 4-digit product, and 2-digit package segments.