13. Local anesthetics

Question 1

Local anesthetics

Answer 1

Generally all have pKa of 8-9 except benzocaine

the anesthetics are …

Toxins that blocks the VGSCs from the extracellular side

and all the other drugs 
Cocaine 
Procaine 
Lidocaine 
Benzocaine 
Mepivacaine 
Tetracaine 
Bupivacaine 
Ropivacaine 
Levobupivacaine 
Prilocaine 
Articaine 
(suffix of -caine)

Question 2

Toxins that blocks the VGSCs from the extracellular side

Answer 2

Tetrodotoxin

Saxitoxin

Question 3

Cocaine

Answer 3

block of amine uptake
AE: cardiovascular and CNS effects
rarely used

Question 4

Procaine

Answer 4

AE: CNS effects, restlessness, convolutions → respiratory depression and cardiovascular collapse

Question 5

Lidocaine

Answer 5

Rapid onset 
2hr DOA
good penetration 
widely used as local anesthesia 
can be used for ventricular arrhythmias 
AE: less CNS effects than Procaine , restlessness, convolutions → respiratory depression and cardiovascular collapse

Question 6

Benzocaine

Answer 6

pKa 3.5 => non-ionized base in pH 7.4
used as surface anesthesia
slowly released and long lasting effect

Question 7

Tetracaine

Answer 7

mainly for spinal and corneal anesthesia

Question 8

Bupivacaine

Answer 8

Long DOA
AE: less CNS effects than Procaine , restlessness, convolutions → respiratory depression but greater cardio toxicity than Lidocaine

Question 9

Ropivacaine

Answer 9

AE: less CNS effects than Procaine , restlessness, convolutions → respiratory depression but less cardio toxicity than Lidocaine

Question 10

Levobupivacaine

Answer 10

AE: less CNS effects than Lidocaine , restlessness, convolutions → respiratory depression but less cardio toxicity than Lidocaine

Question 11

Prilocaine

Answer 11

Widely used
AE: methemoglobinemia

used for epidural anesthesia for obstetric analgesia)

Question 12

Articaine

Answer 12

Used in dentistry