Pyridostigmine
Muscarinic effects are less marked, more nicotinic effects
Duration of action is long (6 hours) than neostigmine
Use:
Myasthenia gravis
Edrophonium
Alcoholic in nature.
Does not possess carbamyl group
It has shorter duration of action because:
1. Binds only with anionic site
2. Weak hydrogen electrostatic bonds are formed with enzymes.
Muscarinic effects are less marked, more nicotinic effects
Use:
1. Diagnosis of myasthenia gravis
2. Supraventricular tachycardia
3. Post operational anticurare use
Echothiophate
Mechanism of Action:
It has longer duration of action because:
- Binds both sites of the enzyme –active and anionic
- Bond formed is stable
Has both Muscarinic effects and Nicotinic effects
Use:
In the treatment of glaucoma only in refractory cases as can lead to cataract formation.
It is poorly lipid soluble as cannot cross blood brain barrier, thus is only topically effective.