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Weight-Based Drug Doses
Enter the patient's weight to compute standard adult doses for the agents you use every day — induction, paralytics, opioids, reversal, vasopressors, and emergency drugs.
dose (mg) = weight (kg) × dose (mg/kg)
Computed weight
70.0 kg · 154.3 lb
Induction agents
Propofol
Induction
105 mg – 175 mg
= 10.50–17.50 mL (10 mg/mL)
↓ 25–50% in elderly, hypovolemic, frail.
Propofol
Maintenance infusion
7000 mcg – 14000 mcg
= 0.70–1.40 mL (10 mg/mL)
mcg/kg/MIN. Sedation 25–75 mcg/kg/min.
Etomidate
Induction
14 mg – 21 mg
= 7.00–10.50 mL (2 mg/mL)
Hemodynamically stable; transient adrenal suppression.
Ketamine
IV induction
70 mg – 140 mg
= 1.40–2.80 mL (50 mg/mL)
IM 4–6 mg/kg. Avoid in active psychosis, severe CAD.
Ketamine
Analgesic infusion
7.0 mg – 35 mg
= 7.00–35.00 mL (1 mg/mL)
mg/kg/HOUR.
Midazolam
Premedication
1.4 mg – 3.5 mg
= 1.40–3.50 mL (1 mg/mL)
Weight-based exceeds typical adult max 2 mg — cap and reassess.
Typical adult: 1–2 mg IV. ↓ in elderly.
Dexmedetomidine
Loading dose
35 mcg – 70 mcg
= 8.75–17.50 mL (4 mcg/mL)
Over 10 min. Often omitted to avoid hemodynamic swings.
Neuromuscular blockers
Succinylcholine
Intubation
70 mg – 105 mg
= 3.50–5.25 mL (20 mg/mL)
Peds infants 2 mg/kg. IM 3–4 mg/kg.
Rocuronium
Intubation
42 mg
= 4.20 mL (10 mg/mL)
RSI: 1.2 mg/kg.
Rocuronium
RSI dose
84 mg
= 8.40 mL (10 mg/mL)
Vecuronium
Intubation
5.6 mg – 7.0 mg
= 5.60–7.00 mL (1 mg/mL)
Cisatracurium
Intubation
11 mg – 14 mg
= 5.25–7.00 mL (2 mg/mL)
Organ-independent (Hofmann). Not reversed by sugammadex.
Opioids
Fentanyl
Induction adjunct
70 mcg – 210 mcg
= 1.40–4.20 mL (50 mcg/mL)
Maintenance 0.5–2 mcg/kg PRN.
Hydromorphone
Post-op analgesia
0.35 mg – 1.4 mg
= 0.35–1.40 mL (1 mg/mL)
Weight-based exceeds typical adult max 1 mg — cap and reassess.
Adult: 0.2–1 mg IV; peak 15 min.
Morphine
Post-op analgesia
3.5 mg – 7.0 mg
= 3.50–7.00 mL (1 mg/mL)
Weight-based exceeds typical adult max 5 mg — cap and reassess.
Histamine release; avoid M6G accumulation in renal failure.
Remifentanil
Infusion
3.5 mcg – 21 mcg
= 0.07–0.42 mL (50 mcg/mL)
mcg/kg/MIN. Always have longer-acting opioid on board.
Sufentanil
Infusion
7.0 mcg – 35 mcg
= 1.40–7.00 mL (5 mcg/mL)
mcg/kg/HOUR.
Reversal agents
Sugammadex
Routine reversal (TOF ≥ 2)
140 mg
= 1.40 mL (100 mg/mL)
Sugammadex
Deep reversal (PTC 1–2)
280 mg
= 2.80 mL (100 mg/mL)
Sugammadex
Immediate (post-RSI roc)
1120 mg
= 11.20 mL (100 mg/mL)
Wait 24 h before re-dosing rocuronium.
Neostigmine
Reversal (TOF ≥ 2)
2.8 mg – 4.9 mg
= 2.80–4.90 mL (1 mg/mL)
Co-admin glycopyrrolate 0.2 mg per 1 mg neostigmine.
Glycopyrrolate
With neostigmine
0.56 mg – 0.98 mg
= 2.80–4.90 mL (0.2 mg/mL)
Approximately 0.2 mg per 1 mg neostigmine.
Naloxone
Opioid reversal (titrate)
0.04 mg – 0.14 mg
= 0.09–0.35 mL (0.4 mg/mL)
Titrate 0.04 mg increments to restore RR without abolishing analgesia.
Flumazenil
Benzo reversal
0.14 mg – 0.70 mg
= 1.40–7.00 mL (0.1 mg/mL)
Avoid in chronic benzo use (seizure risk).
Vasopressors & emergency drugs
Phenylephrine
Bolus
70 mcg – 350 mcg
= 0.70–3.50 mL (100 mcg/mL)
Adult: 50–200 mcg IV. Pure α1.
Ephedrine
Bolus
7.0 mg – 14 mg
= 1.40–2.80 mL (5 mg/mL)
Weight-based exceeds typical adult max 10 mg — cap and reassess.
Adult: 5–10 mg IV.
Epinephrine (anaphylaxis IM)
Anaphylaxis IM
0.70 mg
= 0.70 mL (1 mg/mL)
Weight-based exceeds typical adult max 0.5 mg — cap and reassess.
Anterolateral thigh, repeat q 5–15 min if needed.
Epinephrine (arrest)
ACLS arrest
0.70 mg
= 7.00 mL (0.1 mg/mL)
1 mg IV adult q 3–5 min in arrest.
Atropine
Bradycardia
0.70 mg – 1.4 mg
= 1.75–3.50 mL (0.4 mg/mL)
Weight-based exceeds typical adult max 1 mg — cap and reassess.
Peds 0.02 mg/kg, min 0.1 mg, max 0.5 mg single dose.
Calcium chloride
Hyperkalemia / hypotension
700 mg – 1400 mg
= 7.00–14.00 mL (100 mg/mL)
Weight-based exceeds typical adult max 1000 mg — cap and reassess.
Central line preferred. Adult: 1 g.
Tranexamic acid
Trauma / hemorrhage
1050 mg
= 10.50 mL (100 mg/mL)
Weight-based exceeds typical adult max 1000 mg — cap and reassess.
Adult: 1 g over 10 min within 3 h of injury; then 1 g over 8 h.
Antiemetics & analgesic adjuncts
Ondansetron
PONV prophylaxis
3.5 mg – 7.0 mg
= 1.75–3.50 mL (2 mg/mL)
Weight-based exceeds typical adult max 4 mg — cap and reassess.
Adult: 4 mg IV at end of case.
Dexamethasone
PONV prophylaxis
7.0 mg – 11 mg
= 1.75–2.63 mL (4 mg/mL)
Weight-based exceeds typical adult max 8 mg — cap and reassess.
Give post-induction (perineal itch if awake).
Acetaminophen IV
Multimodal
1050 mg
= 105.00 mL (10 mg/mL)
Weight-based exceeds typical adult max 1000 mg — cap and reassess.
Max 4 g / 24 h adult.
Ketorolac
NSAID analgesia
18 mg – 35 mg
= 1.17–2.33 mL (15 mg/mL)
Weight-based exceeds typical adult max 30 mg — cap and reassess.
Adult: 15–30 mg IV. Avoid in renal failure, bleeding risk.
Lidocaine (anti-cough)
Pre-intubation
70 mg – 105 mg
= 3.50–5.25 mL (20 mg/mL)
Weight-based exceeds typical adult max 100 mg — cap and reassess.
Blunts intubation response; also analgesic infusion 1 mg/kg/h.
Verify every doseagainst the package insert, your institutional protocol, and the patient's physiology. Weight-basis tags (IBW / LBW / ABW) are shown for drugs where choice of weight matters — see the IBW / ABW calculator to derive those.