What type of neuromuscular blocker is Succinylcholine (Anectine)?

Succinylcholine (Anectine) is classified as a depolarizing neuromuscular blocker. This type of neuromuscular blocker works by mimicking the action of acetylcholine at the neuromuscular junction. When succinylcholine is administered, it binds to the nicotinic receptors on the motor end plate of the muscle, causing an initial depolarization that leads to muscle contraction. However, unlike acetylcholine, succinylcholine is resistant to breakdown by acetylcholinesterase, resulting in a prolonged depolarization state. This leads to muscle paralysis as the receptor remains in an inactive state and cannot be stimulated effectively, preventing subsequent muscle contractions.

In the context of other options, non-depolarizing agents work differently by competitively antagonizing the nicotinic receptors without causing initial depolarization, while competitive and reversible are terms more commonly associated with non-depolarizing agents, highlighting their mechanism where neuromuscular transmission can eventually be restored. Thus, succinylcholine's unique mechanism firmly categorizes it as a depolarizing neuromuscular blocker.