Master Succinylcholine with Picmonic for Medicine

With Picmonic, facts become pictures. We've taken what the science shows - image mnemonics work - but we've boosted the effectiveness by building and associating memorable characters, interesting audio stories, and built-in quizzing.

Succinylcholine

Sucker-in-cola
Picmonic
Succinylcholine is a paralytic agent used for surgeries or short procedures, such as intubation. It works by binding at motor nicotinic acetylcholine receptors and keeping myocytes in a depolarized state. This prevents acetylcholine from binding to receptors and prevents muscle contraction. This drug has two phases of action in its mechanism. In phase I, this administered agent is non-reversible. Myocytes still have succinylcholine actively bound to motor-nicotinic receptors and there is a constant depolarized state. Patients often show fasciculations and held-contractions. In phase II, the receptors become sensitized and repolarize. They can only be aroused for action potential with larger amounts of acetylcholine, which is why neostigmine (an acetylcholinesterase inhibitor) can be used to help reverse paralysis in phase II. This paralytic agent can cause malignant hyperthermia in patients, and should not be used in patients in a hyperkalaemic state.
8 KEY FACTS
INDICATIONS
Inducing Paralysis
Wheelchair

This drug is typically used in surgery or for short procedures. It can be used for patients in trauma care to help with intubation, or in those undergoing electroconvulsive therapy.

MECHANISM OF ACTION
Neuromuscular Blocking Drugs
Nerve-muscle Blocks

This drug is considered a neuromuscular blocking drug. It binds to the nicotinic acetylcholine receptor and keeps the muscular action potential stuck in a depolarized state.

Motor Nicotinic receptor
Motor Cigarette Receptor

Succincylcholine exerts its action by binding to the motor nicotinic receptor, which typically accepts endogenous acetylcholine.

ACh Receptor Agonist
A-seagull-cola Receptor Dragonist

This drug mimics ACh action at nicotinic receptor, opening sodium channels and causing membrane depolarization.

Depolarization
D-polar-bear

Succinylcholine keeps cells in sustained depolarization, and prevents muscle contraction. This happens because the cells are unable to repolarize and contract again. This can be observed immediately after IV administration of this drug, as patients fasciculate (contract), and are unable to contract again, even after electrical stimulation.

PHASES OF ACTION
Phase I (Paralysis Non-reversible)
(1) Wand Phase (Wheelchair Locked)

Phase I blocking of this drug is described as maintaining the muscle cell's membrane potential above threshold. The cells are kept in a depolarized state (as succinylcholine is bound to the receptor), as succinylcholine is not broken down quickly. This period of paralysis cannot be overcome, as there is nowhere for acetylcholine to bind.

Phase II (Paralysis Reversible)
(2) Tutu Phase (Wheelchair Reversed and unlocked)

Phase II blocking of this drug is described by the cells being repolarized but blocked. The myocytes become sensitized to their receptor activity and eventually repolarize. ACh receptors are now available but are less sensitive to acetylcholine; they are desensitized. This paralysis is reversible, but needs a larger acetylcholine stimulus to cause contraction.

Neostigmine (Reversal Agent)
Neon-stick-man

Neostigmine is an acetylcholinesterase inhibitor and prevents the breakdown of acetylcholine in the plasma. This leads to an increase in acetylcholine concentration. It is often used to overcome the desensitization experience by paralyzed patients in a Phase II block of succinylcholine.

Unlock all 8 facts & definitions with Picmonic Free!

JOIN FREE

Take the Succinylcholine Quiz

Picmonic's rapid review multiple-choice quiz allows you to assess your knowledge.

START QUIZ NOW

It's worth every penny

Our Story Mnemonics Increase Mastery and Retention

Memorize facts with phonetic mnemonics

Unforgettable characters with concise but impactful videos (2-4 min each)

Ace Your Medical (MD/DO) Classes & Exams with Picmonic:

Over 870,000 students use Picmonic’s picture mnemonics to improve knowledge, retention, and exam performance.

Choose the #1 Medical (MD/DO) student study app.

Picmonic for Medicine (MD/DO) covers information that is relevant to your entire Medical (MD/DO) education. Whether you’re studying for your classes or getting ready to conquer the USMLE Step 1, USMLE Step 2 CK, COMLEX Level 1, or COMLEX Level 2, we’re here to help.

Works better than traditional Medical (MD/DO) flashcards.

Research shows that students who use Picmonic see a 331% improvement in memory retention and a 50% improvement in test scores.