Atracurium
Hello friends! I am Atracurium, a non-depolarizing neuromuscular blocker. I work by competitively blocking nicotinic Nm receptors at the neuromuscular junction, preventing acetylcholine from acting.
Succinylcholine
Haha! I am different! I am the only depolarizing blocker here. I first stimulate the receptor causing fasciculation, then keep it depolarized so the muscle cannot contract again.
Vecuronium
True! Atracurium and I are cousins. We mainly help in surgery, intubation, and mechanical ventilation by producing skeletal muscle relaxation.
Baclofen
You all act peripherally. But I act centrally! I am a GABA-B agonist. I reduce spasticity by inhibiting excitatory neurotransmitter release in the spinal cord.
Diazepam
And I am also central acting! I enhance GABA-A action and reduce muscle spasm. Doctors use me in spasticity, tetanus, and anxiety-associated muscle spasm.
Dantrolene
Listen everyone, I am unique! I act directly on skeletal muscle by blocking ryanodine receptors (RyR1) and reducing calcium release from sarcoplasmic reticulum.
Student
Wow! So what are your uses?
Succinylcholine
I am the fastest for rapid sequence intubation.
Atracurium
I am useful in surgery, especially in patients with liver or kidney problems because I undergo Hofmann elimination.
Baclofen
I treat multiple sclerosis, spinal cord injury spasticity.
Dantrolene
I save lives in malignant hyperthermia!
Diazepam
And I help in muscle spasm and tetanus.
Student
What about adverse effects?
Succinylcholine
Beware! I cause hyperkalemia, postoperative muscle pain, malignant hyperthermia, bradycardia.
Atracurium
I may release histamine causing hypotension and bronchospasm.
Vecuronium
I am safer, but prolonged paralysis can happen.
Baclofen
I can cause sedation, weakness, dizziness.
Diazepam
I cause drowsiness and dependence.
Dantrolene
I may cause muscle weakness and hepatotoxicity.
Neostigmine
Don’t worry! I reverse non-depolarizing block by increasing acetylcholine at NMJ.
Succinylcholine
But not me! My phase I block cannot be reversed by Neostigmine!
Student
Great! Now I understand the classification, mechanism, uses, and adverse effects!
All together
“Relax the muscle, but know the mechanism!”
