PHARMACOLOGY OF LOCAL ANESTHETICS

Question 1

Cocaine

Answer 1

Cocaine has the special property to inhibit synaptic norepinephrine & dopamine reuptake. In the CNS, this causes euphoria, agitation, and seizures; in the cardiovascular system,

Question 2

Lidocaine

Answer 2

• 2/10 potent, fast onset

Lidocaine,is a medication used to numb tissue in a specific area and to treat ventricular tachycardia. It can also be used for nerve blocks.

Question 3

Bupivacaine

Answer 3

• Long lasting
• Racemic Mixture (R is more toxic)… lead to development of ropivacain
• medium onset / potent
• Bupivacaine, in part due to its lipophilicity and potency, has a particularly high propensity to accumulate in the heart and to cause ventricular arrhythmias and severe myocardial depression

Question 4

Ropivacaine

Answer 4

• anatomically pure isomer (bupivacaine)
• medium onset / potent
• Ropivacaine is indicated for local anaesthesia including infiltration, nerve block, epidural and intrathecal anaesthesia in adults and children over 12 years.

Question 5

Benzocaine

Answer 5

• exception to the rule (i.e. the lipophilic uncharged performs blocking action as opposed to the cation)
• pKa = 3.5
• cam cause cyanosis due to methemoglobin formation
• Benzocaine is a local anesthetic commonly used as a topical pain reliever or in cough drops. It is the active ingredient in many over-the-counter anesthetic ointments such as products for oral ulcers.

Question 6

Procaine

Answer 6

• slow onset / not so potent
• poor absorption
• It is used primarily to reduce the pain of intramuscular injection of penicillin, and it is also used in dentistry. Owing to the ubiquity of the trade name Novocain.

Question 7

Articaine

Answer 7

• Dentistry