Drugs for spasticity

Question 1

What drugs are used to treat spasticity?

Answer 1

Baclofen
Botulinum toxin
Dantrolene
Tizanidine

Question 2

What is the MOA of Baclofen?

Answer 2

GABA agonist that reduces excitatory pathways. Provides pain relief by inhibiting substance P action.

Question 3

What conditions is baclofen approved to treat?

Answer 3

multiple sclerosis
muscle spasm
spasticity
spinal cord trauma

Question 4

How is baclofen eliminated?

Answer 4

An orally active drug that undergoes extensive renal elimination. Caution should be exercised
with renal failure/dysfunction as drug accumulation can lead to encephalopathy, abdominal pain,
seizures and respiratory depression

Question 5

What ADEs are associated with Baclofen?

Answer 5

1. Rebound neural activity (BBW)
2. Additive hypotension
3. increased blood glucose
4. drowsiness, confusion, headache (most common)

Question 6

What is the MOA of Dantrolene?

Answer 6

inhibits ryanodine receptors thus preventing Ca release form the sarcoplasmic reticulum. This is called uncoupling of excitation-contraction process

Question 7

How is dantrolene metabolized and eliminated?

Answer 7

Hepatic metabolism

Renal elimination

Question 8

What unique syndrome is connected to dantrolene use?

Answer 8

Floppy child syndrome

Dantrolene crosses the placenta

Question 9

What ADEs are associated with dantrolene?

Answer 9

1. Vfib if combined with CCBs
2. muscle weakness (drooling, enuresis, backache)
3. Possible hepatitis

Question 10

What parameters should be monitored in a patent taking dantrolene?

Answer 10

LFTs