LOCAL ANAESTHETICS SODIUM CHANNEL BLOCKERS: BENZOCAINE, LIGNOCAINE
MECHANISM OF ACTION
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Binds to the S6 subunit of the sodium channel, reducing its permeability for sodium influx into the neuron, thus no depolarisation and propagation of action potentials. Usually affects pain fibres first due to lower myelination as well as smaller diameter making them more susceptible to drug effects.
INDICATIONS:
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Reduce sensation, especially pain of peripheral area before simple surgical procedures
SIDE EFFECTS:
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Further CNS depression, drowsiness which can progress into a coma. Respiratory depression, which can lead to asphyxiation Drugs such as lignocaine, which have a longer duration of action (due to slower metabolism by microsomal enzymes), can further contribute to side effects
