Rocuronium (Zemuron) | Medication Reference

Bedside Snapshot

Primary Use: Rapid sequence intubation (RSI) and maintenance of neuromuscular blockade in OR/ICU
RSI Dose: 1.0-1.2 mg/kg IV (based on ideal/lean body weight)
Onset: ~45-60 seconds at high dose (1.0-1.2 mg/kg); ~60-90 seconds at standard dose (0.6-0.9 mg/kg)
Duration: 45-90 minutes (longer than succinylcholine)
Critical Warning: NO sedative, amnestic, or analgesic properties; patients MUST receive adequate analgesia and sedation before and throughout paralysis
Reversal: Can be reversed with sugammadex (2-4 mg/kg) or neostigmine + glycopyrrolate when appropriate

Brand & Generic Names

Generic Name: Rocuronium bromide
Brand Names: Zemuron, generics

Medication Class

Nondepolarizing neuromuscular blocker (aminosteroid); intermediate-acting. Competitive antagonist at nicotinic acetylcholine receptors at the neuromuscular junction.

Pharmacology

Mechanism of Action:

Competitive antagonist at nicotinic acetylcholine receptors at the neuromuscular junction
Prevents acetylcholine from binding to receptor and depolarizing motor endplate, resulting in flaccid skeletal muscle paralysis
Nondepolarizing: does not cause initial fasciculations like succinylcholine; effect can be reversed with acetylcholinesterase inhibitors (neostigmine) or sugammadex
Blockade follows head-neck-diaphragm progression: small, rapidly moving muscles paralyzed first; diaphragm typically last and recovers first

Pharmacokinetics:

Onset: ~60-90 seconds at 0.6-0.9 mg/kg; ~45-60 seconds at 1.0-1.2 mg/kg (RSI dosing)
Duration: ~30-60 minutes at 0.6 mg/kg; up to 60-90 minutes or more at 1.0-1.2 mg/kg, with variability in critical illness
Distribution: Relatively hydrophilic; volume of distribution ~0.2-0.3 L/kg; limited CNS penetration
Metabolism: Minimal; most excreted unchanged in bile and urine
Elimination: Primarily hepatic/biliary excretion; 10-30% renal excretion. Elimination half-life ~60-90 minutes, prolonged in hepatic dysfunction and possibly severe renal failure
Critical illness, hypothermia, acidosis, and concurrent medications (aminoglycosides, magnesium) may potentiate and prolong blockade

Indications

Rapid sequence intubation (RSI) when nondepolarizing agent preferred or succinylcholine contraindicated (hyperkalemia, neuromuscular disease, major burns, crush injuries, chronic denervation)
Facilitation of mechanical ventilation and control of severe ventilator dyssynchrony in ICU (e.g., severe ARDS), generally after failure of optimized sedation/analgesia
Adjunct in operating room for muscle relaxation during surgery (typically managed by anesthesia)

Dosing & Administration

Available Forms:

IV Solution: Commonly 10 mg/mL rocuronium in multi-dose vials (e.g., 50 mg/5 mL, 100 mg/10 mL)
Ready for IV bolus administration; can be prepared in infusion solutions for continuous ICU paralysis

Standard Adult Dosing (Always Follow Local Protocol):

Indication	Dose	Timing / Repeat	Notes
RSI – standard adult (non-obese)	1.0-1.2 mg/kg IV (ideal/lean body weight)	Single bolus at time of intubation	Onset ~45-60 s; duration 45-90 min
RSI – when slower onset acceptable	0.6-1.0 mg/kg IV	Single bolus	Onset slower at lower doses (~60-90 s); shorter duration
ICU bolus for ventilator dyssynchrony	0.6-1 mg/kg IV	May repeat small boluses (0.1-0.2 mg/kg) as needed	Ensure deep sedation and analgesia before and during paralysis
ICU continuous infusion	5-12 mcg/kg/min IV (0.3-0.7 mg/kg/h)	Titrate to train-of-four (1-2 twitches) and clinical goals	Use lowest effective dose; minimize duration of infusion
Obesity	Dose based on ideal/adjusted body weight	Adjust per response and TOF	Avoid full actual-body-weight dosing to limit prolonged blockade
Hepatic/renal dysfunction	Consider lower end of dosing range	Extend dosing interval or reduce infusion rate	Monitor closely for prolonged paralysis
Reversal (for reference)	Sugammadex 2-4 mg/kg IV; or neostigmine + glycopyrrolate	Given when TOF recovery adequate to reverse	Reversal strategies depend on timing, depth of block, and local availability

Contraindications

Contraindications:

Known hypersensitivity to rocuronium, other aminosteroid NDNMBs (vecuronium, pancuronium), or formulation components
Relative: situations where inability to secure or maintain airway would be catastrophic and nonparalyzed evaluation is essential

Major Precautions:

Neuromuscular disorders: (myasthenia gravis, Lambert-Eaton syndrome) patients often exquisitely sensitive to nondepolarizing NMBs; use lower doses and be prepared for prolonged block
Electrolyte abnormalities: (hypokalemia, hypocalcemia, hypermagnesemia) and acid-base disturbances can potentiate neuromuscular blockade
Hepatic impairment and severe obesity: Prolong duration; consider lower doses and extended monitoring
Anaphylaxis: Rare but reported with all NMBs; be prepared for immediate resuscitation
Never without sedation/analgesia: Never administer rocuronium without adequate sedation and analgesia, both during RSI and for ongoing paralysis

Critical Warning: Rocuronium has NO sedative, amnestic, or analgesic properties. Patients are fully conscious and can feel pain while paralyzed unless adequately sedated and analgesed. ALWAYS ensure deep sedation before and throughout paralysis.

Airway Management: Only use rocuronium when you are confident you can secure and maintain the airway. Have a backup airway plan ready before pushing the paralytic.

Adverse Effects

Common:

Transient hypertension or hypotension
Tachycardia or bradycardia (less autonomic effect than some older agents)
Injection-site pain or discomfort

Serious:

Anaphylaxis, including bronchospasm, hypotension, and cardiovascular collapse
Prolonged neuromuscular blockade and delayed recovery, especially with high doses, infusions, or organ dysfunction
Residual paralysis leading to weakness, hypoventilation, and inability to protect airway if reversal and monitoring inadequate
Contribution to ICU-acquired weakness when used for extended periods in critically ill patients

Special Populations

Obesity:

Dose based on ideal or adjusted body weight, not actual body weight
Using actual body weight can lead to excessive dosing and prolonged paralysis
Monitor train-of-four and adjust subsequent doses accordingly

Hepatic Impairment:

Prolonged duration of action; consider lower doses
Extend dosing intervals or reduce infusion rates
Monitor closely for prolonged paralysis

Renal Impairment:

May have prolonged duration, especially with severe renal failure
Generally safe at standard doses but monitor carefully
Consider dose reduction for continuous infusions

Pediatric Patients:

Standard dose: 0.6-1.2 mg/kg IV depending on indication
Onset may be faster in infants and children
Always ensure adequate sedation and analgesia

Monitoring

Clinical Monitoring:

Continuous ECG, blood pressure, and pulse oximetry during RSI and throughout paralysis
Capnography and ventilator parameters to assess adequacy of ventilation and synchrony
Sedation depth (RASS) and analgesia before induction; once paralyzed, via surrogate markers (hemodynamics, ventilator synchrony, BIS/processed EEG where available)
Neuromuscular monitoring with train-of-four (TOF) stimulation in patients receiving continuous infusions or repeated doses, aiming for 1-2 twitches during maintained paralysis
Frequent reassessment of ongoing need for neuromuscular blockade and daily attempts to lighten or discontinue infusions when clinically appropriate

Clinical Pearls

Post-Intubation Sedation Plan: If you're using rocuronium for RSI, treat it as a long-acting paralytic: have a solid post-intubation sedation and analgesia plan in place BEFORE you push it.

High-Dose Onset vs. Offset: High-dose rocuronium (1.2 mg/kg) gives you succinylcholine-like onset but not succ's quick offset; this is good for difficult ventilations but removes your ability to quickly regain spontaneous respirations.

ARDS Paralysis: In severe ARDS, use rocuronium only after optimizing ventilator settings, sedation, and analgesia; limit continuous paralysis to shortest duration that achieves your ventilatory/oxygenation goals.

TOF Monitoring: Remember that TOF monitoring is only one piece of the puzzle; always correlate with time since last dose, organ function, and clinical context when deciding to redose or reverse.

Sugammadex Reversal: If sugammadex is available, it provides rapid and reliable reversal of rocuronium-induced blockade, especially when deep block persists and you need quick return of neuromuscular function.

References

1. Lexicomp. (2025). Rocuronium: Drug information. Wolters Kluwer.
2. Naguib, M., & Brull, S. J. (2018). Neuromuscular blocking agents and reversal agents. In Miller's Anesthesia (9th ed.). Elsevier.
3. Papazian, L., Forel, J.-M., Gacouin, A., Penot-Ragon, C., Perrin, G., Loundou, A., Jaber, S., Arnal, J.-M., Perez, D., Seghboyan, J.-M., Constantin, J.-M., Courant, P., Lefrant, J.-Y., Guérin, C., Prat, G., Morange, S., & Roch, A. (2010). Neuromuscular blockers in early acute respiratory distress syndrome. New England Journal of Medicine, 363(12), 1107-1116. https://doi.org/10.1056/NEJMoa1005372
4. Marsch, S. C., Steiner, L., Bucher, E., Pargger, H., Schumann, M., Aebi, T., Hunziker, P. R., & Siegemund, M. (2011). Succinylcholine versus rocuronium for rapid sequence intubation in intensive care: A prospective, randomized trial. Critical Care, 15(4), R199. https://doi.org/10.1186/cc10367
5. Farkas, J. (2024). Rapid sequence intubation (RSI) and delayed sequence intubation (DSI). EMCrit Project - Internet Book of Critical Care (IBCC). https://emcrit.org/ibcc/rsi/