Anectine, Quelicin, Sucostrin
Classifications: autonomic nervous system agent; depolarizing skeletal muscle relaxant
Pregnancy Category: C


20 mg/mL, 50 mg/mL, 100 mg/mL injection; 500 mg, 1 g vials


Synthetic, ultrashort-acting depolarizing neuromuscular blocking agent with high affinity for acetylcholine (ACh) receptor sites.

Therapeutic Effects

Initial transient contractions and fasciculations are followed by sustained flaccid skeletal muscle paralysis produced by state of accommodation that develops in adjacent excitable muscle membranes. Rapidly hydrolyzed by plasma pseudocholinesterase.


To produce skeletal muscle relaxation as adjunct to anesthesia; to facilitate intubation and endoscopy, to increase pulmonary compliance in assisted or controlled respiration, and to reduce intensity of muscle contractions in pharmacologically induced or electroshock convulsions.


Hypersensitivity to succinylcholine; family history of malignant hyperthermia.

Cautious Use

During delivery by cesarean section; lactation; kidney, liver, pulmonary, metabolic, or cardiovascular disorders; dehydration, electrolyte imbalance, patients taking digitalis, severe burns or trauma, fractures, spinal cord injuries, degenerative or dystrophic neuromuscular diseases, low plasma pseudocholinesterase levels (recessive genetic trait, but often associated with severe liver disease, severe anemia, dehydration, marked changes in body temperature, exposure to neurotoxic insecticides, certain drugs); collagen diseases, porphyria, intraocular surgery, glaucoma; pregnancy (category C).

Route & Dosage

Surgical and Anesthetic Procedures
Adult: IV 0.3–1.1 mg/kg administered over 10–30 sec, may give additional doses prn IM 2.5–4 mg/kg up to 150 mg
Child: IV 1–2 mg/kg administered over 10–30 sec, may give additional doses prn IM 2.5–4 mg/kg up to 150 mg

Prolonged Muscle Relaxation
Adult: IV 0.5–10 mg/min by continuous infusion


  • Use only freshly prepared solutions; succinylcholine hydrolyzes rapidly with consequent loss of potency.
  • Give initial small test dose (0.1 mg/kg) to determine individual drug sensitivity and recovery time.

PREPARE: Direct: Give undiluted.  Intermittent/Continuous: Dilute 1 g in 500–1000 mL of D5W or NS.  

ADMINISTER: Direct: Give a bolus dose over 30 sec.  Intermittent/Continuous: Preferred. Give at a rate of 0.5–10 mg/min. Do not exceed 10 mg/min.  

INCOMPATIBILITIES Solution/additive: Sodium bicarbonate, thiopental.

Adverse Effects (1%)

CNS: Muscle fasciculations, profound and prolonged muscle relaxation, muscle pain. CV: Bradycardia, tachycardia, hypotension, hypertension, arrhythmias, sinus arrest. Respiratory: Respiratory depression, bronchospasm, hypoxia, apnea. Body as a Whole: Malignant hyperthermia, increased IOP, excessive salivation, enlarged salivary glands. Metabolic: Myoglobinemia, hyperkalemia. GI: Decreased tone and motility of GI tract (large doses).


Drug: Aminoglycosides, colistin, cyclophosphamide, cyclopropane, echothiophate iodide, halothane, lidocaine, MAGNESIUM SALTS, methotrimeprazine, NARCOTIC ANALGESICS, ORGANOPHOSPHAMIDE INSECTICIDES, MAO INHIBITORS, PHENOTHIAZINES, procaine, procainamide, quinidine, quinine, propranolol may prolong neuromuscular blockade; digitalis glycosides may increase risk of cardiac arrhythmias.


Onset: 0.5–1 min IV; 2–3 min IM. Duration: 2–3 min IV; 10–30 min IM. Distribution: Crosses placenta in small amounts. Metabolism: Metabolized in plasma by pseudocholinesterases. Elimination: Excreted in urine.

Nursing Implications

Assessment & Drug Effects

Patient & Family Education

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug