27 emergency drugs

Drug Reference

Adult and pediatric dosing, indications, contraindications, and the pearls that matter at the bedside.

Epinephrine

α/β-adrenergic agonist (catecholamine)

Arrest

Cardiac arrest

1 mg IV/IO (1 mg/10 mL) every 3–5 min

Cardiac arrest (all rhythms) · Anaphylaxis

Amiodarone

Class III antiarrhythmic (K⁺ channel blocker, with I/II/IV effects)

Rhythm

Cardiac arrest

300 mg IV/IO push; second dose 150 mg

VF / pVT refractory to shocks · Stable wide-complex tachycardia

Lidocaine

Class IB antiarrhythmic (Na⁺ channel blocker)

Rhythm

Cardiac arrest

1–1.5 mg/kg IV/IO; then 0.5–0.75 mg/kg every 5–10 min, max 3 mg/kg

VF / pVT (alternative to amiodarone) · Stable monomorphic VT

Adenosine

Endogenous purine nucleoside (AV nodal blocker)

Rhythm

SVT

6 mg rapid IV push + 20 mL NS flush; then 12 mg

Stable regular narrow-complex SVT · Regular monomorphic wide-complex tachycardia (diagnostic/therapeutic)

Atropine

Antimuscarinic (parasympatholytic)

Rhythm

Bradycardia

1 mg IV every 3–5 min, max 3 mg

Symptomatic bradycardia · Organophosphate / nerve agent poisoning

Dopamine

Catecholamine (dose-dependent DA/β₁/α₁)

Pressors

Infusion

5–20 mcg/kg/min, titrate

Symptomatic bradycardia unresponsive to atropine · Hypotension with bradycardia

Norepinephrine

α₁ > β₁ agonist vasopressor

Pressors

Infusion

0.05–0.5 mcg/kg/min (≈ 2–30 mcg/min), titrate to MAP ≥ 65

Septic shock (first-line) · Post-arrest hypotension

Magnesium sulfate

Electrolyte / Ca²⁺ antagonist

Rhythm

Torsades (arrest)

1–2 g IV/IO diluted, push

Torsades de pointes · Hypomagnesemia

Sodium bicarbonate

Alkalinizing agent

Antidotes

TCA toxicity

1–2 mEq/kg IV bolus, repeat to narrow QRS; target pH 7.45–7.55

TCA / sodium channel blocker toxicity · Hyperkalemia (with acidosis)

Naloxone

Opioid receptor antagonist

Antidotes

Opioid overdose

4 mg IN; 0.4–2 mg IV/IM/IO; repeat every 2–3 min

Opioid-induced respiratory depression

Procainamide

Class IA antiarrhythmic

Rhythm

Load

20–50 mg/min IV until arrhythmia suppressed, hypotension, QRS ↑ > 50%, or 17 mg/kg; maintenance 1–4 mg/min

Stable wide-complex tachycardia · Pre-excited AFib (WPW)

Diltiazem

Non-dihydropyridine calcium channel blocker (class IV)

Rhythm

Rate control

0.25 mg/kg (≈ 15–20 mg) IV over 2 min; then 0.35 mg/kg after 15 min; infusion 5–15 mg/h

AFib / flutter rate control · SVT after adenosine

Nitroglycerin

Nitrate vasodilator

Cardiac

Sublingual

0.4 mg SL every 5 min × 3

Ischemic chest pain · Hypertensive acute pulmonary edema

Aspirin

Antiplatelet (COX inhibitor)

Cardiac

ACS

162–325 mg chewed (non-enteric coated), then 81 mg daily

Suspected ACS · Acute ischemic stroke (after lytic window / 24 h after lytics)

Alteplase (tPA)

Fibrinolytic (tissue plasminogen activator)

Cardiac

Stroke

0.9 mg/kg (max 90 mg): 10% bolus over 1 min, remainder over 60 min

Acute ischemic stroke ≤ 4.5 h · STEMI when PCI unavailable

Calcium chloride

Electrolyte (10% = 100 mg/mL; 27.2 mg/mL elemental Ca)

Antidotes

Standard

1 g (10 mL of 10%) IV over 2–5 min (push in arrest)

Hyperkalemia with ECG changes · Calcium channel blocker / β-blocker overdose

Calcium gluconate

Electrolyte (10% = 100 mg/mL; 9.3 mg/mL elemental Ca)

Antidotes

Hyperkalemia

3 g (30 mL of 10%) IV over 5–10 min; repeat if ECG changes persist

Hyperkalemia with ECG changes · Hypocalcemia

Glucagon

Pancreatic hormone (cAMP via glucagon receptor)

Antidotes

β-blocker overdose

3–5 mg IV over 1–2 min, repeat to 10 mg; infusion = effective dose per hour

β-blocker overdose · Anaphylaxis refractory to epinephrine in β-blocked patients

Vasopressin

V₁ receptor agonist (non-adrenergic vasopressor)

Pressors

Septic shock

0.03 U/min fixed (up to 0.04)

Septic shock (add-on to norepinephrine) · Vasodilatory shock

Metoprolol

β₁-selective blocker

Rhythm

IV rate control

2.5–5 mg IV over 2 min; repeat every 5 min, max 15 mg

AFib / flutter rate control · SVT

Heparin (unfractionated)

Indirect thrombin inhibitor (via antithrombin)

Cardiac

ACS / with fibrinolysis

60 U/kg bolus (max 4,000 U), 12 U/kg/h (max 1,000 U/h)

ACS · Pulmonary embolism / DVT

IV lipid emulsion (20%)

Lipid sink / metabolic rescue

Antidotes

LAST / rescue

> 70 kg: 100 mL bolus over 2–3 min then 200–250 mL over 15–20 min. ≤ 70 kg: 1.5 mL/kg bolus then 0.25 mL/kg/min

Local anesthetic systemic toxicity (LAST) · Refractory lipophilic drug toxicity (bupivacaine, TCA, CCB, BB)

Diphenhydramine

H₁ antihistamine

Other

Anaphylaxis adjunct

25–50 mg IV/IM/PO

Adjunct for anaphylaxis (urticaria, itching) · Acute dystonic reactions

Hydrocortisone

Corticosteroid (glucocorticoid + mineralocorticoid)

Other

Septic shock

50 mg IV every 6 h (200 mg/day)

Septic shock requiring ongoing vasopressors · Adrenal crisis

Isoproterenol

Pure β₁/β₂ agonist

Pressors

Infusion

2–10 mcg/min, titrate to HR

Torsades from bradycardia (pause-dependent) as overdrive · Bradycardia in heart transplant

Enoxaparin

Low-molecular-weight heparin (anti-Xa > anti-IIa)

Cardiac

ACS / VTE

1 mg/kg SC every 12 h (CrCl < 30: every 24 h)

NSTE-ACS · STEMI with fibrinolysis

Dextrose

Carbohydrate

Other

Hypoglycemia

25 g IV (50 mL D50 or 250 mL D10)

Hypoglycemia · With insulin for hyperkalemia or HIET