Muscle relaxants

This slide might be helpful for pharmaceutical medicinal chemistry students.

1. By
Shaikh Saniya

3. What are Muscle Relaxants (MR)
A muscle relaxant is a
drug that affects  skeletal
muscle  (Skeletal muscles
are anchored to bone,
either directly or by a
tendon)function and
decreases the muscle tone.
It may be used to
alleviate symptoms such
as muscle spasms, pain,
and hyperreflexia.

6. Skeletal muscle relaxants
Are drugs used to induce muscle relaxation
Classification
 Peripherally acting (Neuromuscular
blockers).
 Centrally acting skeletal muscle relaxants
e.g. Baclofen - Diazepam
 Direct acting skeletal muscle relaxants
e.g. Dantrolene

7. Peripheral Acting Neuromuscular Junction Blockers
(NMJ Blockers)
1) NON DEPOLARIZING NEUROMUSCULAR BLOCKERS1) NON DEPOLARIZING NEUROMUSCULAR BLOCKERS
ISOQUINOLINE DERIVATIVES
 D- TUBOCURARINE
 GALLAMINE
 ATRACURIUM
 CIS ATRACURIUM
 ALCURIUM
 DOXACURIUM
 MIVACURIUM

8. STEROID DERIVATIVES
PANCURONIUM
VECURONIUM
RAPACURONIUM
PIPECURONIUM
ROCURONIUM
2) DEPOLARIZING NEUROMUSCULAR BLOCKERS2) DEPOLARIZING NEUROMUSCULAR BLOCKERS
SUXAMETHONIUM (SUCCINYLCHOLINE)
DECAMETHONIUM

13. Dantrolene

20. Chlormezanone
Chlorzoxazone
Carisoprodol

22. Benzodiazepines (BDZ) as Muscle Relaxants
Benzodiazepines may also be used to relieve skeletal muscle spasticity
and its accompanying pain in a variety of neurologic disorders including
stroke and spinal cord injury.
Spasticity likely results from a relative difference between excitatory
and inhibitory signals in the spinal cord. Consequently, there is
excessive muscle tone and hyperactive stretch reflexes. Benzodiazepines
exert their muscle relaxant properties by central potentiation of GABA
release. In particular, they bind to specific sites on the GABA type A
receptor complex, enhancing the interaction between the receptor and
chloride ion channel.
The metabolism of benzodiazepines occurs in the liver, and some have
active metabolites (e.g., diazepam).
Thus, caution must be exercised to prevent toxicity, including excessive
sedation and cognitive impairment.