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Classification of Local Anesthetics

The classification is a way to categorize local anesthetics based on their chemical structure.
Local anesthetics are drugs used to cause temporary loss of sensory perception, particularly pain, in a specific area of the body without causing loss of consciousness.
They are commonly used in minor surgical procedures, dental work, and other medical applications.
Understanding their classification helps in understanding their pharmacodynamics, pharmacokinetics, and potential side effects.

Here's an explanation of each category:

These are a group of local anesthetics derived from benzoic acid.
Examples include Cocaine, Hexylcaine, Meprylcaine, Cyclomethycaine, Piperocaine.
Cocaine, the first local anesthetic to be used, is notable but not frequently used in modern medical practice due to its addictive properties and potential for abuse.

These are compounds that have been modified from benzoic acid with the addition of an amine group.
Examples include Benzocaine, Butamben, Procaine, Butacaine, Propoxycaine, Tetracaine, Benoxinate.
Benzocaine and Procaine (also known as Novocain) are well-known in this group. Procaine is less potent and has a shorter duration of action compared to newer agents.
Tetracaine is more potent and has a longer duration of action.

These are amide-type local anesthetics, a newer class compared to the ester-type anesthetics (like those in the amino benzoic acid derivatives).
Examples include Lidocaine (also known as Lignocaine), Mepivacaine, Prilocaine, Etidocaine.
Lidocaine is one of the most commonly used local anesthetics due to its rapid onset of action and relatively long duration of effect.
These agents are generally less allergenic than the ester-type local anesthetics.

This category includes local anesthetics that don't fit neatly into the other categories.
Examples are Phenacaine, Diperodon, Dibucaine.
These drugs may have unique structures or properties that distinguish them from the more common classes.
Each of these drugs has its own specific profile in terms of onset, duration, potency, and potential side effects.
Factors such as whether the local anesthetic is a member of the amide or ester class are important because they influence how the drug is metabolized and the likelihood of allergic reactions.
Amides are generally metabolized in the liver, while esters are hydrolyzed by plasma cholinesterases.
This classification is important for healthcare professionals to understand in order to choose the most appropriate local anesthetic for a given patient and procedure.

Here is a table summarizing the classification of local anesthetics, along with examples, their mechanisms of action, uses, and side effects:

Classification	Example	Mechanism of Action	Uses	Side Effects
Benzoic acid derivatives	Cocaine, Hexylcaine, Meprylcaine, Cyclomethycaine, Piperocaine	Block voltage-gated sodium channels, inhibiting nerve conduction	Used for topical anesthesia, minor surgeries	Nervousness, tachycardia, hypertension, potential for addiction (especially cocaine)
Amino benzoic acid derivatives	Benzocaine, Butamben, Procaine, Butacaine, Propoxycaine, Tetracaine, Benoxinate	Block voltage-gated sodium channels, inhibiting nerve conduction	Used for surface anesthesia (esp. mucous membranes), minor procedures	Methemoglobinemia (esp. with benzocaine), allergic reactions, potential for systemic toxicity if used in large amounts
Lidocaine/Anilide derivatives	Lignocaine, Mepivacaine, Prilocaine, Etidocaine	Block voltage-gated sodium channels, inhibiting nerve conduction	Used in dental procedures, minor and major surgery, treatment of arrhythmias (especially lidocaine)	CNS toxicity (seizures, confusion), cardiovascular toxicity, allergic reactions
Miscellaneous	Phenacaine, Diperodon, Dibucaine	Block voltage-gated sodium channels, inhibiting nerve conduction	Used for a variety of anesthesia applications	Varies depending on specific drug, but can include CNS and cardiovascular toxicity, allergic reactions

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