Reversal Agent

Neostigmine

Acetylcholinesterase inhibitor

Mechanism: Inhibits AChE → ↑ACh at NMJ; outcompetes non-depolarizers.

Calculate dose for your patient

Enter weight (kg or lb). Always verify before administration.

Patient weight

Computed weight

70.0 kg · 154.3 lb

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.

Weight is saved on this device for the next calculator you open.

Full dose calculator

Onset

5–10 min

Duration

60 min

Metabolism

Hepatic / plasma esterases; renal excretion (50%).

Dosing

Adult

0.04–0.07 mg/kg IV (max ~5 mg). Co-administer glycopyrrolate 0.2 mg per 1 mg neostigmine.

Pediatric

0.04 mg/kg IV.

Indications

Reversal of non-depolarizing NMB (TOF ≥2)

Contraindications

Mechanical bowel/urinary obstruction
Deep blockade (TOF count 0)

Side Effects

Bradycardia
Bronchospasm
Increased secretions
PONV

Clinical Pearls

1Ceiling effect — cannot reverse deep block; use sugammadex if available.

2Always pair with anti-muscarinic (glycopyrrolate or atropine).

References & Further Reading

1
Textbook
Flood P, Rathmell JP, Shafer S. Stoelting's Pharmacology and Physiology in Anesthetic Practice. 5th ed. Philadelphia: Wolters Kluwer; 2015.
2
Textbook
Gropper MA, Miller RD, Cohen NH, et al., eds. Miller's Anesthesia. 9th ed. Philadelphia: Elsevier; 2020.
3
Textbook
Barash PG, Cullen BF, Stoelting RK, Cahalan MK, Stock MC, Ortega R, Sharar SR, Holt NF. Clinical Anesthesia. 8th ed. Philadelphia: Wolters Kluwer; 2017.
4
Textbook
Adriano A, Morris R, eds. 2021 CA-1 Tutorial Textbook (15th Ed.). Stanford University Medical Center, Department of Anesthesiology.

Citations are provided to direct further study. Always check the most current edition of guidelines and society recommendations — the information in this chapter is a teaching summary, not primary source material.