2. Introduction
Definition
These are the Drug produce relaxant of skeletal muscle by
inhibiting
the transmission of nerve impulse at neuromuscular junction
History
CURARE:- it is the generic name for certain plant extracts
used by South America tribal's as arrow
poison for game Hunting.
 the animal get paralyzed even if not killed.
natural source of curare- Strychnos toxifera,
- Chondrodendron tomentosus
Uses
• general anesthetics to provide muscle Relaxant for surgery
•Painful muscle spasms
•Spastic neurological condition

3. Classifications
I.Neuromuscular BlockingAgent
A. Nondepolarizing (Competitive) blockers)
1.Long acting: d-Tubocurarine, Pancuronium, Doxacurium, Pipercu
2. Intermediate acting: Vecuronium,Atracurium, Cisatracurium, Rocu
Rapacuronium
3. Short acting: Mivacurium
B. Depolarizing blockers
-Succinylcholine, Decamethonium
II.Directly acting agent
-Dantrolene sodium
-Quinine

4. d-Tubocurarine
Source: (CURARE)
Chondrodendron tomentosus,
Strychnos lethalis
It is dextro rotatory competitive
blockers.
Mainly used as an Arrow poison in
hunting
animals

5. MOA
It binds to the Nicotinic receptors on the motor
end
plate N thus blocks the action of Ach by
competitive blockade
If the concn of Ach varies (increase) d-
Tubocurarine bockade is reversed

6. Pharmacological Action
Skeletal muscle
initially paralyses smaller muscle (finger, toes eyes ear)
latter bigger muscle (limbs, neck, trunk followed by intercostal
muscles)
Diaphragm is affected at last N recovery is reversed.
CNS
don’t cross BBB & PB i.e no effect on CNS
Autonomic ganglia
partially blockade both autonomic ganglia & adernal medulla
resulting fall of B.P
Histamine Release
directly act on mast cell & produce Histamin causes >bronchospasm
>increase salivary

7. Pharmacokinetics:
A not absorb from GIT but well
absorbed through IM
D doesn't pass BBB &PB
M in liver
E  urine

8. ADR