salt of Pam in Neopam is Pralidoxime chloride, which
contains a higher percentage of the active drug as compared
to the iodide salt. The principal action of pralidoxime
is to reactivate cholinesterase (mainly outside of the
central nervous system) which has been inactivated by
phosphorylation due to an organophosphate pesticide
or related compound.
The destruction of accumulated acetylcholine can then
proceed and neuromuscular junctions will again function
normally. Pralidoxime also slows the process of "aging"
of phosphorylated cholinesterase to a non-reactivatable
form and detoxifies certain organophosphates by direct
chemical reaction. The drug has its most critical effect
in relieving paralysis of the muscles of the respiratory