From the Guidelines
The primary antidote for non-depolarizing muscle relaxants is neostigmine, typically administered at 0.04 mg/kg IV, combined with an anticholinergic agent such as atropine (0.02 mg/kg) to prevent cholinergic side effects, as recommended by the most recent guidelines 1.
Key Considerations
- For emergency reversal of rocuronium or vecuronium specifically, sugammadex (2-16 mg/kg IV depending on depth of blockade) is more effective and works faster than neostigmine, with the dose of sugammadex required for reversal determined by the degree of neuromuscular blockade 1.
- The concentration of steroid muscle relaxant and the depth of blockade determine the amount of sugammadex needed, with monitoring essential to determine the required dose 1.
- In obese subjects, sugammadex allows faster reversal than neostigmine, and the dose of sugammadex can be calculated based on ideal body mass plus 40% (corrected weight) 1.
Antidote Options
- Neostigmine: 0.04-0.07 mg/kg IV, combined with an anticholinergic agent such as glycopyrrolate (0.01 mg/kg) or atropine (0.01-0.02 mg/kg) 1.
- Sugammadex: 2-16 mg/kg IV, depending on the depth of blockade, with the dose determined by the degree of neuromuscular blockade 1.
Special Considerations
- Depolarizing muscle relaxants like succinylcholine have no specific antidote, and their effects must wear off naturally, which typically takes 5-10 minutes.
- Muscle relaxants taken as medications (like cyclobenzaprine, methocarbamol, or carisoprodol) have no specific antidotes, and treatment focuses on supportive care while the drugs are metabolized and eliminated, with activated charcoal potentially administered in overdose situations if the patient presents within 1-2 hours of ingestion.
From the FDA Drug Label
Glycopyrrolate protects against the peripheral muscarinic effects (e.g., bradycardia and excessive secretions) of cholinergic agents such as neostigmine and pyridostigmine given to reverse the neuromuscular blockade due to non-depolarizing muscle relaxants.
The antidote for muscle relaxants (muscle relaxers) is neostigmine or pyridostigmine, which are cholinergic agents that can reverse the neuromuscular blockade due to non-depolarizing muscle relaxants. However, these agents can have peripheral muscarinic effects, which can be mitigated by glycopyrrolate. 2 2
From the Research
Antidotes for Muscle Relaxants
The antidotes for muscle relaxants are typically anticholinesterases, such as neostigmine, which are used in combination with anticholinergic agents like atropine or glycopyrrolate to prevent unwanted side effects.
- Neostigmine is commonly used to reverse the effects of muscle relaxants, but it can cause bradycardia, bronchospasm, and increased salivation 3, 4, 5, 6.
- Atropine is often used in combination with neostigmine to prevent these side effects, but it can cause tachycardia and other anticholinergic effects 3, 4, 5, 6.
- Glycopyrrolate is an alternative anticholinergic agent that can be used with neostigmine, and it may cause less tachycardia than atropine 4, 5, 6.
- Sugammadex is a novel drug that can selectively bind to and reverse the effects of certain muscle relaxants, and it may be used in cases where neostigmine and anticholinergic agents are not effective or are contraindicated 7.
Comparison of Anticholinergic Agents
Studies have compared the effects of atropine and glycopyrrolate when used with neostigmine to reverse muscle relaxants.
- One study found that glycopyrrolate caused less increase in heart rate than atropine when used with neostigmine 4.
- Another study found that glycopyrrolate was more effective than atropine in preventing bradycardia caused by neostigmine 6.
- A third study found that glycopyrrolate caused fewer supraventricular beats than atropine when used with pyridostigmine to reverse muscle relaxants 5.
Sugammadex as an Alternative
Sugammadex is a novel drug that can selectively bind to and reverse the effects of certain muscle relaxants.
- One study found that sugammadex was effective in reversing residual neuromuscular blockade after incomplete reversal with neostigmine and glycopyrrolate 7.
- Sugammadex may be used in cases where neostigmine and anticholinergic agents are not effective or are contraindicated, but more studies are needed to determine its optimal dose and efficacy 7.