Muscle Relaxants Flashcards
Muscle Spasm definition
The involuntary contraction of a muscle.
Causes of muscle spasms
Epilepsy
HYPOcalcemia
Pain syndromes
Localized skeletal muscle injury (gym warriors)
Drug therapy for muscle spasms.
NSAIDs
Centrally acting muscle relaxants.
A centrally acting muscle relaxant that acts like GABA.
Baclofen
MOA of centrally acting muscle relaxants.
Unknown
These centrally acting muscle relaxants increase the presynaptic inhibition of motor neurons in the CNS.
1) Diazepam
2) Tizanidine
Promotes presynaptic inhibition by mimicing GABA.
Diazepam
Causes presynaptic inhibition by activating alpha 2 receptors.
Tizanidine
Are centrally acting muscle relaxants used to treat muscle spasms or spasticity?
SPASMS
These two centrally acting muscle relaxants can be used for muscle SPASTICITY.
Diazepam and Baclofen
Muscle relaxants used in dentistry for:
Bruxism
TMJ Disorders
Diazepam
Chlorzoxazone
Methocarbamol
Spasticity definition
Spastic paralysis.
Increased muscle tone in a large group of muscles
Spasticity causes movement disorders of ______ _______.
CNS Origin
How is spasticity managed?
Combo of PT and drug therapy.
Common causes of muscle spasticity.
Multiple sclerosis
Cerebral palsy
Spinal cord lesions
Stroke
Drugs for Muscle Spasticity
Baclofen
Diazepam
Dantrolene
This drug for muscle spasticity acts directly on skeletal muscle.
Dantrolene
This drug is used to treat muscle spasticity, is a structural analog of GABA, acts in the CNS, and mechanism is unknown.
Baclofen
Acts within the spinal cord neurons to suppress hyperactive reflexes that regulate muscle movement.
Baclofen
Does Baclofen have direct effects on skeletal muscle?
No
Baclofen acts in the _________, and _______ do not involve the spinal cord.
spinal cord; strokes
What is Baclofen used to treat
Multiple sclerosis
Spinal cord injury
Cerebral palsy
What kind of spasms does Baclofen decrease?
Flexor and extensor
Baclofen suppresses resistance to what kind of movement?
Passive movement
Adverse effects of Baclofen.
- CNS depressant
- Gradual withdrawal over 1-2 weeks to prevent seizure activity and withdrawal syndrome.
- GI symptoms (nausea, constipation).
- Urinary retention
The only member of the benzodiazepine family that’s used to treat muscle spasticity.
Diazepam
Drug used to treat muscle spasticity that facilitates the action of GABA.
Diazepam
Adverse effect of Diazepam
Sedation
This drug is for muscle spasticity, and it acts directly on skeletal muscle.
Dantrolene
Dantrolene MOA.
Prevents the release of Calcium from sarcoplasmic reticulum.
This drug is used to treat malignant hyperthermia
Dantrolene
What is malignant hyperthermia?
Too much Calcium is released from the sarcoplasmic reticulum into the intracellular space of the muscle fiber, causing a metabolic reaction that increases body temperature and degrades muscle.
What is Dantrolene used to treat?
Multiple sclerosis
Cerebral palsy
Spinal cord injury
These are the adverse effects of which drug used to treat muscle spasticity? :
Hepatic toxicity Muscle weakness Drowsiness Diarrhea Acne-like rash
Dantrolene
Dental indications for muscle relaxants.
Bruxism
TMJ Disorders
Tx of head/neck spasms
Reducing post-procedure trismus
When warranted, which drug do dentists prefer as a muscle relaxant?
Diazepam, bc it has:
- Good muscle relaxant properties
- Prolonged action
- Safety
Can CNS muscle relaxants be used for long-term therapy?
No, bc they can become addictive.
Which of the following is most effective in management of malignant hyperthermia?
Baclofen Dantrolene Haloperidol Succinylcholine Vecuronium
Dantrolene
Does Dantrolene have a large effect on Calcium release in cardiac muscle?
No
T/F:
Diazepam causes sedation at most doses required to reduce muscle spasms.
True
What does intrathecal mean?
In the spinal cord.
T/F:
Intrathecal use of baclofen is effective in some refractory cases of muscle spasticity.
True
Which drug has spasmolytic activity and can be used to manage seizures caused by overdose from a local anesthetic?
Diazepam
