Sunday, April 10, 2011

Competitive ganglion blockers

Mechanism of action:

They cause non-depolarizing competitive blockage of ganglia. They compete with acetylcholine at postsynaptic nicotinic receptors.

Actions:
Since the ganglia of sympathetic as well as parasympathetic nervous system are cholinergic so these agents obstruct the outflow through these systems.

Blockade of sympathetic outflow causes a decrease in firmness of the arterioles resulting in the reduced peripheral vascular resistance leading to postural or orthostatic hypotension.

Blockade of parasympathetic outflow causes:

1. A prominent reduction in the motility of the GI tract.

2. Dry mouth

3. Cycloplegia with a decrease in accommodation.

4. Precipitation of urinary retention in men with prostatic hypertrophy.

Adverse effects:
Mostly autonomic effects

No comments: