General Pharmacology of Local Anesthesia

When a local anesthetic is injected near a nerve, it blocks the flow of electrons along the axons and eliminates the pain without loss of consciousness. These effects are reversible. When administering a local anesthetic, one must remember that the larger the diameter of the nerve fiber, the more anesthetic is needed to produce anesthesia. 

Local anesthetics are unstable and insoluble in basic solution. If a local anesthetic lacks an amine, it is insoluble in water and is only used topically. 

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