Succinylcholine

Advantages:

• Rapid onset (30-60 seconds) and short duration (5 minutes)

• Ideal for rapid sequence intubation

Mechanism: 

• Succinylcholine depolarizes muscle cells and prevents repolarization, leading to flaccid paralysis.

• The block is terminated when the drug is broken down by plasma cholinesterase.

Adverse Effects: 

• Hyperkalemia: Muscle depolarization involves efflux of potassium.

• Cardiac arrhythmias: Succinylcholine can bind to acetylcholine receptors in the heart and cause bradycardia.

Contraindications:

• Malignant hyperthermia (MH)

• Pseudocholinesterase deficiency: Lacking the enzyme that metabolizes succinylcholine. Patients present with prolonged muscle paralysis. 

• Duchenne's muscular dystrophy (DMD) and Becker's muscular dystrophy (BMD): At risk of hyperkalemic rhabdomyolysis