Brand names: Anectine, Quelicin
Drug class: Neuromuscular Blocking Agents
VA class: MS300
CAS number: 71-27-2

Medically reviewed by Drugs.com on Oct 14, 2024. Written by ASHP.

Introduction

Depolarizing neuromuscular blocking agent.¹⁰⁰

Uses for Succinylcholine

Skeletal Muscle Relaxation

Production of skeletal muscle relaxation during procedures of short duration (e.g., endotracheal intubation) after general anesthesia has been induced;^{100 b} neuromuscular blocking agent of choice for procedures lasting <3 minutes.^b

Facilitation of endotracheal intubation;¹⁰⁰ because of its rapid onset and short duration of action, generally considered neuromuscular blocking agent of choice in emergency situations when rapid intubation (e.g., rapid sequence intubation) is required.^{100 110 424}

Also used to facilitate mechanical ventilation;¹⁰⁰ however, not used for prolonged neuromuscular blockade in the ICU.^{341 423}

Because of serious adverse effects, restrict use in pediatric population.¹⁰⁰ (See Boxed Warning.)

Succinylcholine Dosage and Administration

General

Dispensing and Administration Precautions

• Facilities and personnel necessary for intubation, administration of oxygen, and respiratory support should be immediately available.^{100 359 424} (See Boxed Warning.)

• Take special precautions (e.g., segregate storage, limit access, affix warning labels to storage containers and final administration containers) to ensure that the drug is not administered without adequate respiratory support.⁴²⁵ Institute for Safe Medication Practices (ISMP) recommends the following wording on auxiliary labels: “Warning: Paralyzing agent—causes respiratory arrest—patient must be ventilated.”⁴²⁵

• To avoid patient distress, generally administer only after unconsciousness has been induced; however, may administer before sedative administered in emergency situations.^{100 359}

• To evaluate patient’s ability to metabolize succinylcholine and to determine individual patient sensitivity and recovery time, a test dose may be administered to spontaneously breathing patient after anesthesia has been induced.^{100 b} (See Test Dose under Dosage and Administration.)

• Assess neuromuscular blockade and recovery in patients undergoing anesthesia;^c careful assessment with a peripheral nerve stimulator is recommended during continuous IV infusions to monitor the degree of neuromuscular blockade, to detect the development of phase II block, and to minimize the possibility of overdosage.¹⁰⁰

Administration

Administer IV or IM.¹⁰⁰ IV administration is preferred; if necessary, may administer IM in infants or older patients in whom a suitable vein is not accessible.¹⁰⁰ Some clinicians recommend that IM administration be reserved for life-threatening situations.⁴²⁴

For specific procedures and techniques of administration, consult specialized references.

IV Administration

For solution and drug compatibility information, see Compatibility under Stability.

For prolonged procedures, may administer by continuous IV infusion (preferably) or intermittent IV injection.¹⁰⁰

Multiple fractional doses generally should not be used; repeated fractional doses and, to a lesser extent, continuous infusion, may lead to tachyphylaxis.^b (See Prolonged or Repeated Administration under Cautions.)

Dilution

For continuous IV infusion, dilute succinylcholine chloride to the desired concentration (usually 1–2 mg/mL) in a compatible IV solution (e.g., 5% dextrose injection, 0.9% sodium chloride injection).¹⁰⁰ A concentration of 1 mg/mL usually is used for optimum dosage control; 2 mg/mL may be preferred if amount of fluid should be limited.^{100 b}

Do not admix with alkaline solutions.¹⁰⁰ (See Compatibility under Stability.)

IM Administration

May administer by IM injection if IV access not available.^{100 b}

Dosage

Available as succinylcholine chloride; dosage expressed in terms of the salt.¹⁰⁰

Carefully adjust dosage according to individual requirements and response.¹⁰⁰

Pediatric Patients

Skeletal Muscle Relaxation

IV

Infants and small children: 2 mg/kg.¹⁰⁰

Older children and adolescents: 1 mg/kg.¹⁰⁰

Continuous IV infusions considered unsafe in neonates and children.^b (See Pediatric Use under Cautions.)

IM

Infants and older children: If IM administration necessary, a dose of up to 3–4 mg/kg (maximum 150 mg) may be given.¹⁰⁰ Onset of effect approximately 2–3 minutes.¹⁰⁰

Adults

Skeletal Muscle Relaxation

Test Dose

IV

To evaluate sensitivity to succinylcholine in patients with reduced plasma cholinesterase activity, administer test dose of 5–10 mg or cautiously administer a 1-mg/mL solution by slow IV infusion.¹⁰⁰

Dosage for Procedure

IV

For short procedures, usual dose is 0.6 mg/kg (range 0.3–1.1 mg/kg).¹⁰⁰ Following administration of this dose, neuromuscular blockade generally is attained in approximately 1 minute and persists for 4–6 minutes.¹⁰⁰

For prolonged procedures, usual dosage is 2.5–4.3 mg/minute by continuous IV infusion; adjust rate (range: 0.5–10 mg/minute) depending on patient’s response and requirements.¹⁰⁰ Alternatively, administer by intermittent IV injection: initially 0.3–1.1 mg/kg, followed by additional doses of 0.04–0.07 mg/kg as necessary to maintain adequate muscle relaxation.¹⁰⁰

For rapid sequence intubation, usual dose is 1.5 mg/kg; generally produces onset of effect within 45 seconds and duration of paralysis of about 10 minutes.^{110 424}

IM

If IM administration necessary, a dose of up to 3–4 mg/kg (maximum 150 mg) may be given.¹⁰⁰ Onset of effect approximately 2–3 minutes.¹⁰⁰

Prescribing Limits

Pediatric Patients

Skeletal Muscle Relaxation

IM

Maximum total dose 150 mg.¹⁰⁰

Adults

Skeletal Muscle Relaxation

IM

Maximum total dose 150 mg.¹⁰⁰

Special Populations

Geriatric Patients

Careful dosage selection recommended due to possible age-related decrease in hepatic, renal, and/or cardiac function and concomitant disease and drug therapy; initiate therapy at low end of dosage range.^b

Patients with Reduced Plasma Cholinesterase Activity

Administer small test dose (5–10 mg) or cautiously administer 1-mg/mL solution by slow IV infusion.¹⁰⁰ (See Reduced Plasma Cholinesterase Activity under Cautions.)

Cautions for Succinylcholine

Contraindications

• Personal or familial history of malignant hyperthermia.¹⁰⁰

• Skeletal muscle myopathies.¹⁰⁰

• Upper motor neuron injury, multiple trauma, extensive or severe burns, extensive denervation of skeletal muscle because of CNS disease or injury.¹⁰⁰ (See Hyperkalemia under Cautions.)

• Known hypersensitivity to succinylcholine or any ingredient in the formulation.¹⁰⁰

Warnings/Precautions

Warnings

Hyperkalemia

Potential for acute rhabdomyolysis with hyperkalemia.¹⁰⁰ (See Boxed Warning and also see Pediatric Use under Cautions.)

Possible severe hyperkalemia resulting in serious cardiac arrhythmias or cardiac arrest in patients with upper motor neuron injury, multiple trauma, extensive or severe burns, or extensive denervation of skeletal muscle because of CNS disease or injury; use is contraindicated in these patients.¹⁰⁰ Risk of hyperkalemia depends on extent and location of the injury, increases over time, usually peaks 7–10 days after the injury,¹⁰⁰ and can persist for >6 months after neural injury.^b

Use with extreme caution in patients with preexisting hyperkalemia or those at increased risk of hyperkalemia (e.g., those with paraplegia, chronic abdominal infection, tetanus, subarachnoid hemorrhage, degenerative or dystrophic neuromuscular disease, or conditions that may cause degeneration of central and peripheral nervous systems).^{100 b}

Use with extreme caution in patients receiving quinidine or cardiac glycosides or those with suspected cardiac glycoside toxicity (due to potential for hyperkalemia).^{100 b}

Sensitivity Reactions

Hypersensitivity Reactions

Serious hypersensitivity reactions, including anaphylaxis, reported rarely.¹⁰⁰ Potential for cross-sensitivity with other neuromuscular blocking agents (both depolarizing and nondepolarizing).¹⁰⁰

Take appropriate precautions; emergency treatment for anaphylaxis should be immediately available.¹⁰⁰

General Precautions

Administration Precautions

Because of the potential for severely compromised respiratory function and other complications, take special precautions during administration.¹⁰⁰ (See Boxed Warning and also see General under Dosage and Administration.)

Malignant Hyperthermia

Possible fatal malignant hyperthermia; manifested by a rapid, profound elevation in body temperature and sometimes extreme muscular rigidity.¹⁰⁰ Risk increases with concomitant administration of inhalation anesthetics.¹⁰⁰ (See Specific Drugs under Interactions.)

If malignant hyperthermia occurs, discontinue all anesthetic agents and initiate IV dantrolene therapy in conjunction with supportive measures (e.g., administering oxygen, treating metabolic acidosis, instituting cooling procedures); maintain urinary output and monitor serum electrolytes.^{100 c}

Bradycardia

Possible profound bradycardia resulting from vagal stimulation and accompanied by hypotension and cardiac arrhythmias (e.g., nodal rhythms, extrasystoles, bigeminy, AV block, cardiac arrest).^{100 b}

Occurs most commonly with repeated administration and in children¹⁰⁰ (see Pediatric Use under Cautions).

Prior administration of atropine may inhibit vagal stimulation and reduce occurrence of bradycardia.^{100 b}

Use with extreme caution in patients with electrolyte disturbances, those receiving quinidine or cardiac glycosides, or those with suspected cardiac glycoside toxicity.^b

Prolonged or Repeated Administration

Possible tachyphylaxis with repeated administration;¹⁰⁰ multiple fractional doses alone generally should not be used.^b

Possible prolonged neuromuscular blockade due to change of the characteristic depolarizing neuromuscular block (phase I block) to a phase II block.¹⁰⁰

To reverse phase II block, may administer a cholinesterase inhibitor (e.g., neostigmine, pyridostigmine, edrophonium), in conjunction with an antimuscarinic (e.g., atropine, glycopyrrolate) to prevent disturbances in cardiac rhythm.¹⁰⁰ Use a peripheral nerve stimulator to confirm change to phase II block prior to administering cholinesterase inhibitor.¹⁰⁰

To ensure complete hydrolysis of succinylcholine by plasma pseudocholinesterase prior to administration of cholinesterase inhibitor, do not attempt reversal unless spontaneous recovery of muscle twitch has been observed for ≥20 minutes and has plateaued, with further recovery from neuromuscular blockade occurring slowly.¹⁰⁰ (See Actions.)

Intracranial Pressure

Possible slight, transient increase in intracranial pressure.¹⁰⁰

Intragastric Pressure

Possible increased intragastric pressure secondary to fasciculation of abdominal muscles; potential for regurgitation and possible aspiration of stomach contents.¹⁰⁰ May be prevented by prior administration of small dose of nondepolarizing neuromuscular blocking agent.^b

Reduced Plasma Cholinesterase Activity

Possible prolonged respiratory depression and muscle relaxation in patients with reduced plasma cholinesterase activity.^{100 b}

Plasma cholinesterase activity may be reduced in patients heterozygous or homozygous for the atypical pseudocholinesterase gene, pregnant women, and patients with severe hepatic or renal disease, malnutrition, infections, severe anemia, severe dehydration, burns, cancer, collagen diseases, myxedema, decompensated heart disease, peptic ulcer disease, or abnormal body temperature.^{100 b}

Some clinicians recommend determining plasma pseudocholinesterase activity prior to administration.^b

Administer with extreme caution and in reduced doses, if at all, in patients with abnormally low pseudocholinesterase concentrations.^b If low concentrations are suspected, a test dose or cautious continuous IV infusion may be administered. (See Patients with Reduced Plasma Cholinesterase Activity under Dosage and Administration.)

Treat apnea or prolonged muscle paralysis with controlled respiration.¹⁰⁰ Administration of fresh whole blood or plasma may restore pseudocholinesterase concentrations.^b

Electrolyte Disturbances

Possible prolonged neuromuscular blockade in patients with electrolyte disturbances (e.g., hypocalcemia, hypokalemia).¹⁰⁰ Use with caution.^c (See Hyperkalemia and also Bradycardia under Cautions.)

Histamine Release

Possible histamine release; manifestations associated with histamine release (e.g., flushing, erythema, pruritus, urticaria, wheal formation, wheezing, bronchospasm, hypotension) uncommon at usual dosages.^{100 b}

Orthopedic Precautions

Use with caution in patients with fractures, dislocations, or muscular spasms; initial muscle fasciculation may cause additional trauma.¹⁰⁰

Ophthalmic Effects

Possible increased intraocular pressure.¹⁰⁰

Use not recommended in patients with angle-closure glaucoma or penetrating eye injuries.¹⁰⁰ Use with extreme caution, if at all, during ocular surgery; nondepolarizing neuromuscular blocking agent may be preferred.^b

Specific Populations

Pregnancy

Category C.¹⁰⁰ (See Reduced Plasma Cholinesterase Activity under Cautions.)

Lactation

Not known whether succinylcholine is distributed into milk.¹⁰⁰ Caution advised if succinylcholine is used.¹⁰⁰

Pediatric Use

Possible acute rhabdomyolysis with hyperkalemia followed by ventricular arrhythmias, cardiac arrest, and death; usually occurs in males ≤8 years of age.¹⁰⁰ If cardiac arrest occurs, initiate treatment for hyperkalemia.¹⁰⁰ Prolonged or extraordinary resuscitative measures may be required.¹⁰⁰ Use in children and adolescents should be reserved for those undergoing emergency intubation, those in whom an airway should be secured immediately (e.g., those with laryngospasm, difficult airway, or full stomach), or those in whom a suitable vein is not accessible and IM administration is needed.¹⁰⁰

Possible profound bradycardia or, rarely, asystole when administered by rapid IV injection.^{100 b} Risk increases with repeated doses; consider pretreatment with atropine.¹⁰⁰

Possible risk of malignant hyperthermia; institute appropriate therapy if malignant hyperthermia occurs.¹⁰⁰ Rarely, myoglobinuria and myoglobinemia have been reported in conjunction with malignant hyperthermia and muscle rigidity.^b Continuous IV infusions are considered unsafe in neonates and children due to risk of malignant hyperthermia.^b (See Malignant Hyperthermia under Cautions.)

Geriatric Use

Use with caution due to greater frequency of decreased hepatic, renal, and/or cardiac function and of concomitant disease and drug therapy observed in the elderly.¹⁰⁰ Titrate dosage carefully.^b

Hepatic Impairment

Possible decreased plasma cholinesterase activity in patients with severe hepatic impairment;¹⁰⁰ use with caution.^c (See Elimination: Special Populations, under Pharmacokinetics.)

Renal Impairment

Possible decreased plasma cholinesterase activity in patients with severe renal impairment.¹⁰⁰ Possible accumulation of succinylmonocholine, resulting in prolonged apnea.^b Use with caution.^c

Common Adverse Effects

Various degrees of skeletal muscle weakness.

Drug Interactions

Specific Drugs

Succinylcholine Pharmacokinetics

Absorption

Bioavailability

Poorly absorbed from the GI tract.^c

Onset

Following IV administration, onset is rapid; complete muscle relaxation occurs within 0.5–1 minute following 10- to 30-mg dose.^b

Following IM administration, onset occurs in about 2–3 minutes.^b

Duration

Following IV administration, duration of action is short (about 2–3 minutes following 10- to 30-mg dose; effects gradually dissipate within 10 minutes).^b Duration of action may be prolonged when administered as continuous IV infusion or in fractional doses.^b

Following IM administration, duration of action ranges from 10–30 minutes.^b

Special Populations

Duration of action is prolonged in patients with low plasma pseudocholinesterase concentrations.^b

Distribution

Extent

Crosses the placenta in small amounts.¹⁰⁰

Elimination

Metabolism

Rapidly hydrolyzed by plasma pseudocholinesterase to succinylmonocholine and then more slowly to succinic acid and choline.¹⁰⁰

Elimination Route

Excreted in urine as active and inactive metabolites and small amounts of unchanged drug.^{100 b c}

Special Populations

Severe hepatic impairment may decrease plasma pseudocholinesterase activity, resulting in increased duration of action due to reduced metabolism.^c

In patients with renal impairment, possible decreased plasma pseudocholinesterase activity and possible accumulation of succinylmonocholine.^b

Stability

Storage

Parenteral

Injection

2–8°C.¹⁰⁰ Multiple-dose vials stable up to 14 days at room temperature.¹⁰⁰

Compatibility

Parenteral

May be incompatible with alkaline solutions with pH >8.5 (e.g., barbiturate solutions).¹⁰⁰

Solution CompatibilityHID

Drug Compatibility

Actions

• Produces skeletal muscle relaxation by causing a decreased response to acetylcholine (ACh) at the myoneural (neuromuscular) junction of skeletal muscle.^c

• Exhibits high affinity for ACh receptor sites and produces depolarization of motor end-plate at myoneural junction, resulting in transient twitching or fasciculation of skeletal muscles, followed by muscle paralysis (phase I block).^c

• Prolonged or repeated administration results in gradual and variable transition to phase II block, which resembles nondepolarizing block.¹⁰⁰

• Phase I block is potentiated by cholinesterase inhibitors and can be reversed by nondepolarizing neuromuscular blocking agents; fully established phase II block can be reversed by cholinesterase inhibitors and potentiated by nondepolarizing agents.^c

• Stimulates cardiac vagus and subsequently sympathetic ganglia.^c

• Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.¹⁰⁰

• Importance of informing clinician of existing or contemplated concomitant therapy, including prescription and OTC drugs, as well as any concomitant illnesses (e.g., cardiovascular disease, neuromuscular disease).¹⁰⁰

• Importance of informing patients of other important precautionary information.¹⁰⁰ (See Cautions.)

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

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