Table of Contents
How does amide local anesthetics work?
Amide local anesthetics are commonly used for pain control during minor surgery. Local anesthesia causes a temporary loss of sensation, including pain, without depressing the consciousness. It acts within nerve fibers to inhibit the rapid inflow of sodium necessary for impulse generation.
How are ester local anesthetics metabolized?
Ester-type local anesthetics are metabolized by plasma pseudocholinesterase and their metabolites are excreted through urine. Amide-type local anesthetics compared to ester-type anesthetics are more commonly used due to their better pharmacokinetic properties and lower incidence of adverse effects [1R].
What are amide type local anesthetics?
The amide local anesthetics including lidocaine, bupivacaine and ropivacaine are commonly used for pain control during minor surgery or invasive procedures such as biopsies, small excisions or dental work.
How do you remember ester and amide local anesthetics?
A pharmacist once taught me this trick to remember how to tell whether a local anesthetic is an ester or an amide: Look at the generic name of the local anesthetic. If it contains 2 of the letter “i” then it is an amide. If it contains only 1 letter “i” then it is an ester.
Which local anesthetics are esters?
Commonly used ester LAs include chloroprocaine, procaine, and tetracaine. The commonly used amide LAs include lidocaine, bupivacaine, ropivacaine, mepivacaine, and outside the United States, levobupivacaine.
What is a unit of anesthesia?
The proper way to report anesthesia time is to record it in minutes. One unit of time is recorded for each 15-minute increment of anesthesia time. For example, a 45-minute procedure, from start to finish, would incur three units of anesthesia time.
What happens when amides are hydrolyzed with acid?
The acid acts as a catalyst for the reaction between the amide and water. The alkaline hydrolysis of amides actually involves reaction with hydroxide ions, but the result is similar enough that it is still classed as hydrolysis. Hydrolysis under acidic conditions
What is the mechanism of hydrolysis of esters?
As the hydrolysis of esters can be driven by acid-catalyzed mechanism, and since the product of this reaction is also acid, this reaction can perform autocatalysis. Acid-catalyzed hydrolysis of esters is a first-order reaction while base-catalyzed hydrolysis of esters is second ordered. Hydrolysis of esters is a temperature dependent reaction.
What are the products of the hydrolysis of esters with tertiary alkyl groups?
And that is the acid-catalyzed hydrolysis of esters containing a tertiary alkyl group: The products are a carboxylic acid and alcohol just as expected. However, the mechanism is a little different.
Why is alkaline hydrolysis preferred over acid catalyzed reaction?
Alkaline hydrolysis is preferred over acid-catalyzed hydrolysis because it is an irreversible reaction, and one of the products is salt of the carboxylic acid. It is soluble in water and can be easily separated from the reaction mixture. What is formed when ester reacts with sodium hydroxide?