Neuromuscular Blocking Agents/ Nicotinic Antagonists

(Competitive, non-depolarizing)

d-Tubocurarine (Jexin®)

Dimethyl tubocurarine (Gallamine®)

Pancuronium (Pavulon®)

Atracurium (Tracrium®)

Vecuronium (Norcuron®)

Pipercuronium (Arduan®)

Doxacurium (Nuromax®)

Mivacurium (Mivacron®)

Rocuronium (Zemuron®)

Cisatracurium (Nimbex®)

 Neuromuscular Blocking Agents/ Nicotinic Antagonists

(Competitive, Non-depolarizing)

MOA: Blocks transmission at neuromuscular junction and causes flaccid paralysis

Used to relax muscles during surgery

SE: Respiratory paralysis, bradycardia, tachycardia, bronchial constriction, hypotension

d-Tubocurarine

Jexin®

DOA: 150 minutes

Naturally occuring alkaloid

Neuromuscular blocking agent (Competitive)

Dimethyl tubocurarine

Gallamine®

Neuromuscular blocking agent (Competitive)

Pancuronium

Pavulon®

DOA: 120-150 minutes

Neuromuscular blocking agent (Competitive)

Atracurium

Tracrium®

DOA: 60 minutes

Neuromuscular blocking agent (Competitive)

Vecuronium

Norcuron®

DOA: 60 minutes

Neuromuscular blocking agent (Competitive)

Pipercuronium

Arduan®

Neuromuscular blocking agent (Competitive)

Doxacurium

Nuromax®

Neuromuscular blocking agent (Competitive)

Mivacurium

Mivacron®

Neuromuscular blocking agent (Competitive)

Rocuronium

Zemuron®

DOA: 30 minutes

Neuromuscular blocking agent (Competitive)

Cisatracurium

Nimbex®

Neuromuscular blocking agent (Competitive)

Succinylcholine

Anectine®

MOA: Depolarizes skeletal muscles and leads to flaccid paralysis

Used to relax muscles during surgery

SE: Respiratory depression, bradycardia, tachycardia, bronchial constriction, hypotension

Neromuscular blocking agent (Depolarizing)

Nonspecific Centrally Acting Agents

Carisoprodol (Soma®)

Chlorzoxazone (Paraflex®)

Meprobamate (Equanil®)

Metaxalone (Skelaxin®)

Methocarbamol (Robaxin®)

Orphenadrine (Norflex®)

Cyclobenzaprine (Flexeril®)

Nonspecific Centrally Acting Agents

 MOA: Decreases synaptic transmission of impulses in the spinal cord

SE: Drowsiness, dizziness, dry mouth, constipation

Used to control spasticity associated with painful musculoskelatal conditions

Structures are similar to TCAs

Carisoprodol

Soma®

Metabolism: Can be N-dealkylated

Notes: Is a controlled substance in Florida (C-IV) but not federally

Nonspecific centrally acting agent

Chlorzoxazone

Paraflex®

Metabolism: 6-hydroxylation to glucoronidation

Nonspecific centrally acting agent

Meprobamate

Equanil®

N-dealkylated metabolite of Soma

Nonspecific centrally acting agent

Metaxalone

Skelaxin®

Nonspecific centrally acting agent

Methocarbamol

Robaxin®

Metabolism: 1. para-hydroxylation of the ring

2. O-demethylation 3. Conjugation

Nonspecific centrally acting agent

Orphenadrine

Norflex®

Has similar structure to diphenhydramine

Nonspecific centrally acting agent

Cyclobenzaprine

Flexeril®

*Ardley has it listed as miscellaneous but Fitz has it listed with the Nonspecific*

Nonspecific centrally acting agent

GABA Receptor Agonists

Diazepam (Valium®)

Baclofen (Lioresal®)

Diazepam

Valium®

MOA: Enhaces the action of GABA by opening the chloride channel which leads to hyperpolarization

SE: Hypotension, dizziness

Indirect GABA Receptor Agonist

Baclofen

Lioresal®

MOA: Acts as an agonist at GABA_b receptors in the spinal cord and it hyperpolarizes the post synaptic neuron by opening the K⁺ channel.

SE: Drowsiness, weakness

Oral dose: 5-20 mg 3 times/day

Warning: Abrupt withdrawal can lead to hallucinations and other CNS effects

Direct GABA receptor agonist 

Tizanidine

Zanaflex®

MOA: Binds to alpha-2 receptors in the spinal cord and inhibits the release of excitatory neurotransmitters (mainly Glutamate)

Used to control spasticity with multiple sclerosis and stroke

Dose: 4-8 mg 3 times/day

SE: Hypotension, dizziness

Alpha-2 Agonist

Dantrolene Sodium

Dantrium®

MOA: Binds to ryanodine receptor (RyR1)

Used to control spasms associated with multiple sclerosis, stroke, spinal cord injuries, and cerebral palsy

SE: Fatigue, dizziness, drowsiness, liver toxicity

Direct Acting Agent

Riluzole

Rilutek®

MOA: Glutamate inhibitor

Used for muscle weakness associated with ALS

Miscellaneous Agents