Muscle Relaxants Flashcards Preview

Pharmacology > Muscle Relaxants > Flashcards

Flashcards in Muscle Relaxants Deck (32):
1

MOA of spasmolytics

depresses polysynaptic reflexes in spinal chord

2

MOA of cyclobenzaprine

related to TCA, serotonergic, noradrenergic, anticholenergic, antimuscarinic
reduces tonic somatic motor activity influencing both alpha and gamma motor neurons

3

MOA of orphenadrine

anticholinergic,

4

Therapeutic use of cyclobenzaprine

short term treatment of skeletal muscle spasms, not effective to treat spasticity

5

Therapeutic use of methocarbamol

short term treatment of skeletal muscle spasms, not effective to treat spasticity

6

MOA of methocarbamol

related to TCAs, general CNS depression

7

Side effects of cyclobenzaprine (4)

drowsiness
loss of coordination
anticholinergic side effects
dizziness

8

Side effects of methocarbamol (5)

drowsiness
loss of coordination
light-headedness
dizziness
discoloration of urine

9

Side effects of parenteral administration of methocarbamol (4)

synscope, hypotension, bradycardia
ataxia and vertigo
seizures
hemolysis

10

Toxic effects of cyclobenzaprine (5)

areflexia
flaccid paralysis
respiratory depression
tachycardia
hypotension

11

Toxic effects of methocarbamol (2)

CNS depression
respiratory depression

12

Principal therapeutic use of oral baclophen

decrease spasticity caused by multiple sclerosis and SCI

13

Side uses of baclophen

hiccups
neuropathic pain- including trigeminal neuralgia

14

Advantages of intrathecal baclofen

low dose, fewer side effects

15

MOA of baclophen

Binding to pre and post synaptic GABA-B receptors
Pre-synaptic, reduces Ca+ influx and transmitter release
Post-synaptic- activation of K+ chanels and arachidonic acid signalling
Reduces substance P release from nociceptive afferent nerve terminals

16

Therapeutic use of tizanidine

decrease spasticity in MS and SCI

17

MOA of tizanidine

Central acting, alpha 2 adrenergic agonist
inhibits release of EAA in spinal interneurons

18

Therapeutic use of botulinum toxin

decrease spasticity in cerebral palsy, stroke, traumatic brain injury, advance MS
dystonia
excessive sweating

19

MOA of botulinum toxin

localized chemodenervation in 24-72 hrs lasting for 12-16 weeks

20

Contraindications of botulinum toxin

excess weakness, may not be exact

21

Therapeutic use of diazepam

adjunct to baclophen in treating spasticity in patients with spinal cord lesions and cerebral palsy
treatment of muscle spasm

22

MOA of diazepam

activates GABA-A receptors, increasing Cl- , causing pre-synaptic inhibition

23

Pharmacokinetics of diazepam

two active metabolites half life 20-80 hrs

24

Therapeutic use of Dantrolene sodium

decrease spaciticity in UMN lesions
decrease spacticity in stroke and SCI
Malignant hyperthermia
Neuroleptic malignant syndrome

25

MOA of dantrolene sodium

blocks fast muscle fibers and muscle contraction
reduces release of calcium from the SR

26

Pharmacokinetics of dantrolene sodium

Peak concentration 3-6 hrs after oral administration
Metabolized by liver
half life 15 hrs

27

Contraindications of dantrolene sodium

muscle weakness, consideration for ALS

28

MOA of gabapentin

acts on N-type Ca+ channels to reduce neuropathic pain

29

Special attention, baclofen

abrupt sensation associated with seizures

30

Special attention, diazepam

withdrawl syndrome, dependence potential

31

special attention tizanidine

not to be used with antihypertensives, or clonidine. dose related elevation in liver transaminases

32

special attention dantroline

hepatotoxicity