Bedside Snapshot

Use It For: Paralysis after intubation for controlled ventilation (ICU, transport); intubation when succinylcholine and rocuronium are unsuitable; short-course paralysis in refractory severe ARDS (not routine); surgical relaxation
Adult Dose: Intubation: 0.08–0.1 mg/kg IV (labeled initial dose)
Maintenance: 0.01–0.015 mg/kg IV every 12–15 min as needed
Infusion: 1 mcg/kg/min, titrated by TOF (OR 0.8–1.2; ICU often 0.8–2.3)
Pediatric Dose: 10–16 yr: 0.08–0.1 mg/kg IV, as adults. 1–10 yr: may need slightly more, more often. 7 wk–1 yr: more sensitive, slower recovery. Under 7 wk and infusions: not established
Onset / Duration: IV: intubating conditions in 2.5–3 min, peak 3–5 min / 25–40 min to 25% recovery (clinical block about 25–30 min); 95% recovery at 45–65 min; longer in liver disease and infants
Do Not Give / Hold If: Hypersensitivity to vecuronium; no airway, ventilation and rescue equipment ready; not deeply sedated; no twitch on TOF (hold doses and infusion)
Watch For: Awareness under paralysis (sedation lapses); apnea from disconnection or tube dislodgement (lost EtCO₂); anaphylaxis (hypotension, bronchospasm); prolonged weakness after days of infusion
Reversal / Rescue: Sugammadex 2 mg/kg (second twitch back) or 4 mg/kg (1–2 post-tetanic counts), actual weight; 16 mg/kg not studied after vecuronium. Ventilate until recovered
Must Remember: Paralysis is not sedation, and wrong-drug errors kill: sedate before and throughout, confirm the vial, and label every reconstituted 1 mg/mL syringe

Indications

Emergency & Prehospital

Continued paralysis after RSI: intubated, sedated patients who need controlled ventilation for transport (Paramedic/CCT, per local protocol)
Intubation when the usual paralytics are unavailable or unsuitable: a fallback for when succinylcholine is contraindicated and rocuronium is not available. Onset is slower, so it is a poor first choice for RSI

ED / ICU / Transport

Facilitation of mechanical ventilation: FDA-labeled. SCCM 2016 suggests a trial when hypoxemia, respiratory acidosis or hemodynamic compromise is life-threatening
Severe ARDS, short course only: not routine. Save it for refractory hypoxemia or ventilator dyssynchrony after sedation and ventilator optimization. The ATS 2024 population is PaO₂/FiO₂ ≤100 mmHg within 48 hr of onset. ESICM 2023 recommends against routine continuous NMBA infusion in moderate-to-severe ARDS not due to COVID-19 (strong recommendation, moderate evidence). ATS 2024 conditionally suggests NMBA only in early severe ARDS (low certainty). The large trials used cisatracurium. ACURASYS (2010, 90-day HR 0.68) and ROSE (2019, 90-day death 42.5% vs 42.8%, no difference) both did. Vecuronium was not studied. ICM 2020 rapid guideline: a 48-hour infusion is a reasonable option when deep sedation is needed for lung-protective ventilation or proning.
Overt shivering during targeted temperature management: SCCM 2016 says it may be used. Hypothermia prolongs the block (see Precautions)
Status asthmaticus: not for routine use. SCCM 2016 suggests against routine paralysis

Other Uses

Adjunct to general anesthesia: tracheal intubation and skeletal muscle relaxation during surgery (FDA-labeled)

Dosing & Administration

Doses vary by protocol; follow local protocols and medical direction.

Available Forms

Lyophilized powder, single-dose vial: 10 mg; reconstitute with 10 mL to 1 mg/mL
Lyophilized powder, single-dose vial: 20 mg; reconstitute with 20 mL to 1 mg/mL
Route: labeled for IV use only.

High-Alert Medication: accidental vecuronium causes respiratory arrest and death. That happens especially when the wrong vial is selected or the dose reaches a patient it was not meant for. Confirm the product. Label every syringe. Have a second clinician check any infusion and pump setting.

Adult Dosing

Indication	Dose & Route	Repeat / Max	Notes
Intubation (initial dose)	0.08–0.1 mg/kg IV bolus	Single dose; labeled recommended initial dose. Larger doses: see next row	High-alert Good intubating conditions in 2.5–3 min, so not for crash airways. Sedation/induction agent first.
Larger initial dose (selected patients)	0.15–0.28 mg/kg IV bolus	Max 0.28 mg/kg (highest labeled dose)	High-alert Onset shortens and duration lengthens as the dose rises. Only with ventilation assured for a long block.
After succinylcholine intubation	0.04–0.06 mg/kg IV (balanced anesthesia: 0.05–0.06 mg/kg)	Single dose; give only once succinylcholine is wearing off	High-alert Prior succinylcholine strengthens and prolongs the block; clinical duration 25–30 min.
Maintenance boluses	0.01–0.015 mg/kg IV	First dose usually 25–40 min after the intubating dose, then every 12–15 min as needed; titrate to twitch response	High-alert Little cumulative effect with repeated doses in surgery. Give larger, less frequent doses if preferred.
ICU or transport bolus paralysis	0.1 mg/kg IV	Repeat only once a twitch returns on train-of-four (TOF), or, without a nerve stimulator, for clinical signs of returning muscle function; no fixed max	High-alert Deep sedation and analgesia first. Long-term ICU dosing is not established in labeling: follow the unit protocol.
Continuous infusion	1 mcg/kg/min IV, started 20–40 min after the intubating dose	No fixed max: titrate to TOF; OR average 0.8–1.2, ICU often 0.8–2.3 mcg/kg/min	High-alert See Continuous Infusion. Hold the infusion if there is no twitch.

Dosing weight is ambiguous on the label. It says body weight but does not say which kind. For obese ICU patients, SCCM 2016 suggests ideal or adjusted body weight, not actual weight. For renal and hepatic considerations, see Special Populations.

Pediatric Dosing

Indication	Dose (per kg) & Route	Max Single / Max Total	Notes
Intubation, age 10–16 yr	0.08–0.1 mg/kg IV, as for adults	Labeled initial dose as for adults; maintenance as for adults	High-alert Same mg/kg requirements as adults.
Intubation, age 1–10 yr	0.08–0.1 mg/kg IV	Titrate to TOF; no labeled mg cap	High-alert May need a slightly higher initial dose and more frequent supplementation than adults.
Infants 7 weeks to 1 yr	No separate labeled dose; dose by nerve stimulator response	Titrate to TOF; no labeled mg cap	High-alert Moderately more sensitive per mg/kg; recovery takes about 1.5 times as long as in adults.
Neonates and infants under 7 weeks	Not established in children under 7 weeks	—	Specialist (NICU or pediatric anesthesia) use only. Never reconstitute with bacteriostatic water for a newborn.
Continuous infusion, any age	Not established in children	—	Labeling has insufficient pediatric infusion data; use a PICU protocol.

See also pediatric weight-based dosing and the pediatric airway page.

Continuous Infusion

Setting	Example Concentration	Start	Titrate	Usual Range / Max
Operating room (adults)	0.1 mg/mL (10 mg in 100 mL) or 0.2 mg/mL (20 mg in 100 mL), example (institution-specific)	1 mcg/kg/min, 20–40 min after the intubating dose, once early spontaneous recovery from the bolus is seen	To about 90% twitch suppression	Average 0.8–1.2 mcg/kg/min (label); no fixed max. Reduce 25–60% under steady-state enflurane or isoflurane, 45–60 min after the intubating dose; may not be needed with halothane
ICU or transport (adults)	Same as OR (institution-specific)	1 mcg/kg/min, once early spontaneous recovery from the bolus is seen	To 1–2 TOF twitches plus clinical assessment (ventilator triggering, shivering)	Often about 0.8–2.3 mcg/kg/min; no fixed max. Labeling gives no ICU dose recommendation: follow the unit protocol

Preparation & Administration

Reconstitution: sterile water, 0.9% sodium chloride, D5W, D5NS or lactated Ringer’s (10 mg in 10 mL = 1 mg/mL). Without preservative: refrigerate and use within 24 hr. With bacteriostatic water: use within 5 days; never for newborns.
Push: IV bolus through a free-flowing line, then flush.
Infusion math: at 0.1 mg/mL, 1 mcg/kg/min is 0.01 mL/kg/min. For a 70 kg patient, that is 0.7 mL/min, or 42 mL/hr. At 0.2 mg/mL, halve the rate.
Line: the reconstituted solution is acidic. Never share a line or syringe with alkaline drugs such as barbiturates (thiopental).
Pump: smart pump with a drug library for every infusion; discard unused infusion solution.

Contraindications & Precautions

Contraindications

Known hypersensitivity to vecuronium
No means to ventilate: do not give it unless intubation, ventilation, oxygen and reversal agents are immediately available and you are ready to control breathing (label warning)

Precautions

Previous anaphylaxis to any neuromuscular blocker: cross-reactivity is reported across the class. Ask first.
Myasthenia gravis or Lambert-Eaton syndrome: small doses may have profound effects. Use a small test dose and a nerve stimulator.
Liver disease (cirrhosis, cholestasis): recovery may take twice as long.
Renal failure: dialysis-prepared patients see no meaningful prolongation. Anephric patients facing non-elective surgery: consider a lower initial dose. With prolonged ICU use, the 3-desacetyl metabolite can build up.
Hypothermia (including temperature control after cardiac arrest): the block gets longer. Clearance falls about 11% per °C below 38 °C, and mild hypothermia roughly doubles the duration. Use the lowest effective dose. Judge depth by TOF, and check shivering and ventilator triggering too.
Slow circulation (heart failure, older age, edema): onset is delayed. Do not raise the dose to speed it up.
Long-term ICU use, severe obesity: prolonged weakness, plus airway and ventilation problems.
Malignant hyperthermia: there is not enough data to say whether it is a trigger.

Hold / Reassess If

No response to the first twitch (T1) on TOF: give no further doses and stop the infusion until a response returns
Sedation and analgesia are not running or the patient is not deeply sedated
Daily, in the ICU: reassess the need, try a pause, and stop as soon as possible
Before any brain-death examination: stop it and confirm the block has worn off (TOF twitches present)
At end of life or withdrawal of life support: stop it, as SCCM 2016 suggests
Before extubation: TOF ratio <0.9 (residual block)

FDA Boxed Warning: only adequately trained clinicians should give vecuronium. They need to know its actions, characteristics and hazards.

Risk of death from medication errors: paralysis can progress to respiratory arrest and death. That is most likely when the drug reaches a patient it was not meant for. Confirm the product. Store it with the cap intact and apart from other vials. Label and communicate every dose.

Adverse Effects & Toxicity

Common

Prolonged or residual block: the most frequent adverse reaction. It ranges from weakness to prolonged apnea.
Inadequate reversal: it can happen with all nondepolarizing blockers
Hemodynamics: blood pressure does not change in a clinically significant way. Heart rate is unchanged or down by up to 8% in studies.
Hypersensitivity (rare): bronchospasm, hypotension or tachycardia, sometimes with urticaria or erythema. Clinical doses cause no chemically mediated histamine release.
Muscle atrophy and weakness after long-term ICU use

Serious / Life-Threatening

Effect	Recognition	Management
Anaphylaxis	Hypotension, bronchospasm, rising airway pressures, urticaria; can be fatal	Stop the drug; epinephrine and anaphylaxis protocol
Awareness under paralysis	Paralysis hides distress: the patient cannot move or signal	Deep sedation and analgesia before and throughout; treat lapses in sedation as urgent
Unrecognized hypoventilation	Disconnection, tube dislodgement or ventilator failure causes apnea with no respiratory effort; falling SpO₂, lost EtCO₂ waveform	Bag-valve ventilation with oxygen, confirm tube position, check the circuit and ventilator
Prolonged paralysis, ICU-acquired weakness	Weakness when weaning after days of paralysis; worse with steroids, aminoglycosides, electrolyte or acid-base problems	Shortest duration, TOF plus clinical assessment, daily pauses, physiotherapy; ventilate until recovery
Residual block after extubation	Weak cough or head lift, hypoventilation, desaturation, TOF ratio <0.9	Support ventilation or reintubate; reverse with sugammadex

Overdose & Toxicity Management

Signs: skeletal muscle weakness, less respiratory reserve, low tidal volume or apnea. Opioids and sedatives may add respiratory depression.
Immediate management: keep the airway open and ventilate, by hand or by machine, until recovery is confirmed. Keep the patient sedated while paralyzed.
Antidote: sugammadex IV, dosed by actual body weight in adults and in children from birth. Give 2 mg/kg once the second twitch (T2) returns. Give 4 mg/kg at 1–2 post-tetanic counts with no TOF twitch. The 16 mg/kg immediate-reversal dose has not been studied after vecuronium. Sugammadex has not been studied for reversal after ICU use, and it is not recommended with severe renal impairment (CrCl <30 mL/min). After reversal with up to 4 mg/kg, wait at least 4 hr before re-dosing vecuronium 0.1 mg/kg (24 hr with mild or moderate renal impairment). If paralysis is needed sooner, use a nonsteroidal blocker such as cisatracurium.
Alternative: neostigmine with glycopyrrolate or atropine is a reasonable choice only at minimal depth (TOF ratio 0.4 to <0.9), a conditional ASA 2023 suggestion. For deep, moderate or shallow block, ASA 2023 recommends sugammadex. Neostigmine should not be used for deep block. Reversal may fail within 30 min in debilitation, carcinomatosis, or with interacting antibiotics or anesthetics, so keep ventilating. See the neostigmine page for how this differs from its FDA label.
Extracorporeal removal: the effect of hemodialysis or peritoneal dialysis is unknown.

Monitoring

Parameter	When / How Often	Target / Act If
Clinical: TOF (peripheral nerve stimulator)	Before each repeat dose; regularly during infusions, per unit protocol	ICU target 1–2 twitches, combined with clinical signs such as ventilator triggering and shivering (TOF alone is not enough). No twitch: hold doses and stop the infusion. In hypothermia, expect a longer block and rely on clinical signs as well.
Clinical: sedation and analgesia depth	Before paralysis, then regularly per protocol	Deep sedation before and during paralysis. Processed EEG (BIS) is optional: SCCM 2016 makes no recommendation.
Clinical: ventilation	Continuous waveform EtCO₂, SpO₂, ventilator alarms	Loss of EtCO₂ waveform or falling SpO₂: bag-valve ventilation and check the tube. Correlate with an ABG.
Clinical: heart rate, blood pressure	Continuous	Vecuronium has no meaningful hemodynamic effect: new hypotension suggests another cause (sedatives, hypovolemia, anaphylaxis).
Clinical: eyes, skin, venous thromboembolism	Scheduled, every shift	Lubricating drops or gel and eyelid closure (SCCM strong recommendation); pressure-injury care; VTE prophylaxis.
Laboratory: glucose	Per ICU protocol during infusion	Keep glucose below 180 mg/dL, per SCCM 2016.
Laboratory: electrolytes, acid-base	Daily and with unexplained change in block	Correct K⁺, Ca²⁺ and Mg²⁺ disturbances and acidosis, which can enhance or weaken block.
Laboratory: renal and hepatic function	Daily during infusions	Rising creatinine or abnormal liver panel: expect slower recovery; lower the rate by TOF.
Recovery before extubation	After the last dose or reversal	Quantitative TOF ratio ≥0.9 at the adductor pollicis (not the eye muscles) per ASA 2023. Keep monitoring after reversal.

Interactions & Compatibility

Clinically Significant Interactions

Drug / Class	Effect	What To Do
Succinylcholine given first	Stronger, longer vecuronium block	Wait until succinylcholine is wearing off; use the reduced dose (Adult Dosing)
Aminoglycosides, tetracyclines, polymyxin B, colistin, bacitracin	Intensify or cause block themselves; prolonged paralysis	Expect a longer block; monitor TOF; slower reversal possible
Magnesium sulfate	Enhances block (e.g., preeclampsia therapy)	Expect a stronger block; titrate to TOF
Volatile anesthetics (isoflurane, enflurane, halothane)	Enhance block once at steady state	Reduce the initial dose about 15%. Under steady-state enflurane or isoflurane, reduce the infusion 25–60% (a reduction may not be needed with halothane)
Quinidine, procainamide	Potentiate block; quinidine given during recovery may cause recurrent paralysis	Monitor ventilation and TOF after the dose
Other nondepolarizing blockers	Additive effect	Avoid combining; monitor TOF
Corticosteroids (long-term ICU paralysis)	Associated with prolonged weakness and myopathy	Shortest paralysis; daily reassessment

IV Compatibility

Diluents: 0.9% sodium chloride, D5W, D5NS, lactated Ringer’s, sterile water (use within 24 hr).
Incompatible: alkaline solutions such as barbiturates (thiopental), in the same syringe, needle or line.
Verify with an institutional compatibility resource.

Special Populations

Pediatrics: requirements change with age. Ages 10–16 dose as adults. Ages 1–10 need a slightly higher and more frequent dose. Infants are more sensitive, with slower recovery. Pediatric infusion dosing is not established. See the Pediatric Dosing table.
Neonates: safety and effectiveness are not established under 7 weeks. Do not reconstitute with bacteriostatic water for a newborn.
Pregnancy: no animal reproduction studies have been conducted. At cesarean after succinylcholine, umbilical venous levels were 11% of maternal, and 5-minute Apgar scores were ≥9. Magnesium given for toxemia of pregnancy may enhance the block. Late in pregnancy, elimination half-life is shorter (35–40 min). Source: FDA label (reference 1).
Lactation: it is not known whether it enters human milk. Use with caution (reference 1).
Older Adults: onset may be delayed, so do not raise the dose to speed it up. Start at the low end and monitor neuromuscular function closely. Source: FDA label (reference 1).
Renal Impairment: patients optimally prepared by dialysis see no clinically significant prolongation. In anephric patients facing non-elective surgery, a lower initial dose should be considered. Recovery measurements do not differ significantly from healthy patients. The 3-desacetyl metabolite is recovered in urine, and it has been rarely detected after prolonged ICU use. Cisatracurium is generally the preferred infusion agent. Its metabolism avoids accumulation in renal dysfunction (Source: FDA label, reference 1; IBCC, reference 8).
Hepatic Impairment: in cirrhosis or cholestasis, some recovery measurements may be doubled. The label gives no dosage recommendation for impaired liver function (reference 1). Titrate strictly to TOF.
Hypothermia / Temperature Control: mild hypothermia doubles the duration of block (Caldwell 2000, reference 7). Use the lowest effective dose and follow a unit protocol. Allow for residual paralysis before any neurologic, prognostic or brain-death exam after cardiac arrest.
Obesity / Dosing Weight: for NMBA dosing in obese patients, SCCM 2016 suggests ideal or adjusted body weight, not actual weight. Sugammadex is dosed on actual body weight (reference 2).
Myasthenia Gravis / Lambert-Eaton Syndrome: small doses have profound effects. Guide reduced doses by TOF.

Field & Transport Considerations

Scope: paramedics credentialed for RSI or post-intubation paralysis, critical-care and flight teams, and RNs under orders. Scope varies by state and agency protocol.
Storage & Stability: store the powder at 20–25 °C (68–77 °F). Excursions to 15–30 °C (59–86 °F) are allowed. Protect it from light and keep it in the carton. Reconstituted without preservative, refrigerate and use within 24 hr.
Carried Concentration: powder vials must be reconstituted to 1 mg/mL. Label the syringe at once. Store paralytics apart from look-alike vials, with caps intact.
After Intubation: confirm tube position with waveform EtCO₂, start sedation and analgesia before or with vecuronium, and redose them on schedule. Keep ventilator alarms on.
Infusions in Transport: use a smart pump and a labeled line. Verify concentration and mcg/kg/min at handoff. Carry a nerve stimulator if available. Without one, redose only for clinical signs of returning muscle function (movement, ventilator triggering, breathing over the ventilator), and first reassess and redose sedation and analgesia, per protocol.
Handoff Essentials: time and dose (mg and mg/kg, weight used) of each vecuronium dose. Sedation and analgesia given. Last TOF. Any reversal agent. Neurologic exam before paralysis.

Clinical Pearls

Paralysis is not sedation: vecuronium does nothing to consciousness or pain. A calm-looking paralyzed patient may still be awake. Sedation has to start before the block and keep running through it.

Why it is a poor crash-RSI drug: standard doses need 2.5–3 min to give intubating conditions. Bigger doses shorten that wait only by making the block much longer (reference 1). For intubating critically ill patients, IBCC picks rocuronium as the drug of choice (reference 8).

No vecuronium "rescue reversal" dose: sugammadex 16 mg/kg was only studied after rocuronium (reference 2). If a vecuronium intubation fails, do not count on immediate reversal. Go to the failed-airway algorithm.

Exam discriminator: vecuronium vs rocuronium vs cisatracurium

Vecuronium: an aminosteroid cleared by the liver and bile. It has an active metabolite, and sugammadex reverses it (references 1 and 2)
Rocuronium: an aminosteroid that sugammadex reverses (reference 2)
Cisatracurium: a benzylisoquinoline that clears by Hofmann elimination, independent of organ function (reference 8). Sugammadex does not reverse it (reference 2)

Do not trust the twitch monitor alone: edema, electrode position and muscle choice distort TOF in ICU patients. Pair the twitch count with ventilator triggering, shivering and the bedside picture. Try a paralysis pause daily.

Protect the eyes: paralyzed patients cannot blink. Scheduled lubrication and eyelid closure is the one strong recommendation in the SCCM sustained-paralysis guideline.

ARDS evidence has shifted: in 2010, ACURASYS (cisatracurium) showed benefit against deep sedation. In 2019, ROSE found no mortality difference with lighter sedation. ESICM 2023 recommends against routine NMBA infusion in moderate-to-severe ARDS not due to COVID-19. Where an infusion is used, ICM 2020 considers 48 hr a reasonable course.

Pharmacology

Mechanism of Action

Competes with acetylcholine for cholinergic receptors at the motor end plate → no depolarization → flaccid paralysis.
Aminosteroid; ED₉₀ averages 0.057 mg/kg (0.049–0.062), so the 0.08–0.1 mg/kg intubating dose is about 1.4–1.75 times the ED₉₀.
No known effect on consciousness, pain threshold or cerebration; histamine release is not characterized at clinical doses, and cardiovascular effects are slight when ventilation is maintained.
Block is reversed by acetylcholinesterase inhibitors once spontaneous recovery has begun, or bound by sugammadex, which forms a complex with it (reference 2).

Source: FDA label (reference 1).

Pharmacokinetics

Route	Onset	Peak	Duration
IV (0.08–0.1 mg/kg)	First twitch depression about 1 min; intubating conditions 2.5–3 min	Maximum block 3–5 min	25–40 min to 25% recovery; 95% recovery at 45–65 min

Half-life: elimination 65–75 min (also in renal failure patients at transplant); distribution about 4 min; shorter (35–40 min) in late pregnancy.
Metabolism: the liver plays a role in metabolism and excretion. The 3-desacetyl metabolite is judged by animal screening (dogs and cats) to have 50% or more of the parent potency. Only unchanged drug is found in plasma after surgical use; the metabolite has been rarely detected, and then only after prolonged ICU use, and it is recovered in urine in some patients (up to 10% of the dose).
Elimination: bile 25–50% within 42 hr; urine 3–35% within 24 hr.
Distribution: volume 300–400 mL/kg; protein binding 60–80%; clearance 3–4.5 mL/kg/min.