One-Pager

High-Alert Meds and Insulin

ISMP list, insulin timing, rule of 15, anticoagulants and reversal, digoxin, IV potassium, naloxone, safe orders and the rights

Reviewed by Alex G, BSN, RN, CEN, CCRN, CMC, NREMT-P · Checked against current sources October 2026

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Heparin vs Warfarin: aPTT vs INR, HIT, Bridging, Antidotes and DOAC Reversal

9:40 video · Chapters and full transcript

High-alert meds (ISMP 2024)

Exam study summary, not a bedside tool. Doses are typical adult ranges; follow your institution's protocols.

High-alert: errors may not be more common, but do more harm. Key ISMP groups:

• Insulin (U-500 singled out); oral sulfonylureas
• Anticoagulants (including LMWH, DOACs); thrombolytics
• Opioids; IV moderate sedation; paralytics
• Concentrated KCl and potassium phosphate, hypertonic saline, IV magnesium
• IV vasopressors, antiarrhythmics, inotropes (digoxin, milrinone)
• Chemotherapy, epidural and intrathecal drugs, TPN, IV oxytocin
• New in 2024: tranexamic acid injection

Insulin types

• Rapid: 0–15 min before the meal; regular: 30 min before. NPO or meal late: follow orders.
• Mixing with NPH: clear (regular or rapid) first, then cloudy NPH.
• Glargine, degludec: never mixed or IV. IV insulin is usually regular; it lowers K.
• U-500, U-300, U-200: never draw from the pen into a syringe; U-500 vials need a U-500 syringe.

Hypoglycemia: rule of 15

ADA 2026: level 1, 54–69 mg/dL; level 2, under 54; level 3, needs another person's help.

Signs: shaky, sweaty, hungry, fast pulse, confused. Beta-blockers can mask the fast pulse, not sweating.

1. Under 70, alert, can swallow: 15 g fast carbs (4 oz juice or regular soda, 3–4 glucose tablets).
2. Recheck in 15 min; repeat if still under 70.
3. Above 70, no meal soon: eat a snack; ongoing insulin can cause another low.
4. Not alert or cannot swallow: nothing by mouth; glucagon or IV dextrose per protocol.

Anticoagulants

• Heparin: aPTT 1.5–2× control (label; exam convention 1.5–2.5×) or anti-Xa 0.3–0.7 units/mL, per protocol. Platelets fall over 50% or under 100,000, or new clots: stop heparin, evaluate for HIT.
• Warfarin: INR 2–3 (mechanical mitral valve 2.5–3.5); overlap heparin or LMWH 5 days or more, until INR is in range 24 h.
• Warfarin major bleed: IV vitamin K 5–10 mg. High INR, no bleeding: hold; over 10, add oral vitamin K.
• Steady vitamin K intake (leafy greens), not zero.
• Enoxaparin: no aPTT, but check platelets (CBC); keep the air bubble; do not rub the site.
• No DOACs with mechanical heart valves.

Digoxin and IV potassium

• Apical pulse for a full minute; under 60 (adult), hold and notify unless parameters differ.
• Check K first. Low K, low Mg, high Ca, kidney impairment and older age raise toxicity risk.
• Toxicity: anorexia, nausea, vomiting (often first); yellow-green vision; confusion; bradycardia, heart block, PVCs.
• Label range 0.5–2 ng/mL; adverse effects likelier above 1.2. Antidote: digoxin immune fab.

• KCl: premixed bags; no concentrate on patient-care units.
• Always diluted, on a pump; usually 10 mEq/h or less.
• Check urine output and kidney function first.

Opioids and naloxone

• Check sedation and breathing before each dose.
• Respiratory depression: stop the opioid, stimulate, support breathing, give naloxone.
• Naloxone (adult): overdose 0.4–2 mg IV, IM or subcut; post-op 0.1–0.2 mg IV; repeat every 2–3 min.
• Many opioids outlast naloxone: keep monitoring, redose as ordered.
• Too much, too fast: pain returns, BP and pulse rise, vomiting; withdrawal if opioid-dependent.

Look-alikes and the rights

Tall Man letters flag the part that differs: hydrALAZINE / hydrOXYzine.

Orders: "units", never "U"; no trailing zero (5 mg, not 5.0); always a leading zero (0.5 mg).

• Six rights (patient, drug, dose, time, route, documentation), checked 3 times.
• Added rights: reason, response, education, refusal.
• At least two identifiers, such as name and date of birth.
• LPN/LVN duties with IV and high-alert drugs vary by state and employer.

Related one-pagers

• Pharmacology by Class and SuffixDrug-name stems, prototypes, the check before each dose, key adverse effects, teaching, antidotes and look-alike traps
• Dosage Calculation for the ExamCore formulas, IV rates, safe-dose checks, NCLEX rounding and conversions
• Insulin Types Chart: Onset, Peak and DurationRapid, short, intermediate, long, ultra-long and premixed insulins with brand names, meal timing, mixing, hypoglycemia and NCLEX traps

Calculators for this topic

• Units/hr to mL/hr (Heparin, Insulin)

Sources

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