Local Anesthetics

Question 1

Cocaine

Answer 1

Indirect Sympathomimetic Used as local anesthtic for ear, nose, and throat surgery Hypertension, paranoia, abuse, seizures, cadiac ischemia and infarction, cardiac arrhythmias Blocks Na+/K+-ATPase thus blocking reuptake of NE, serotonin, and dopamine. Potentiates effects of these NT. Increase NE can lead to vasoconstriction and ischemia. Also blocks Na+ channel leading to some anesthethic properties

Question 2

Lidocaine

Answer 2

Blocks voltage gated Na+ channels Used as surface, infiltration, IV regional, nerve block, spinal, and epidural anesthetic Risk of toxicity when high concentrations and large areas are involved. Causes drowsiness and could cause heart toxicity (at 10 micrograms/ml). Prolonged when given with Epi Rapid onset (30-90 seconds), lasts 1-1.5 hours