Vasoconstrictors

Question 1

• What type of structure is articaine?
• is it a 5 membered thiophene ring or 6 membered benzene ring?
• What happens to the additional ester side chain in articaine?
• How long has it been in the US?
• Whats the selling point of articaine?
• What’s controversial about it?

Answer 1

• Amide structure that is metabolized in the liver
• Its a 5 member thiophene ring
• Additional ester chain is metabolised by esterases in blood and tissue
• Available in the US since 2000
• the selling point is that it quickly diffuses and hydrolyzed with low systemic effects
• Paraesthesia controversy

Question 2

Which vasoconstrictor agents interact with SNS receptors?

Answer 2

• Alpha 1 and alpha 2
• Beta 1 and Beta 2

Question 3

What are the two classifications of the two vasoconstrictors? and what falls into each category?

Answer 3

• Catceloamines
  
  • Epi
  • Noreepi
  • Dopamine
  • levonordefrin
  • isoproternol
• Non Catcholamines
  
  • Amphetamines
  • Meth
  • Hydroxy-amphetamine
  • Ephedrine
  • Mephentermine

Question 4

What are the differences between the molecular structures of epinephrine, norepinephrine and levonordefrin?

Answer 4

Question 5

what is Epi interaction with SNS?

Answer 5

• Alpha 1 just peripheral vasoconstriction which is what we want
• Alpha 2 Located in CNS control SNS activity and inhibites NE release. Transient hypertension followed by hypotension
• Beta 1 increases HR and contractility we dont want that
  
  • Positive chrontropic and inotropic
• Beta 2
  
  • Bronchodilation
  • skeletal muscle vasodialation
  • Low dose epi may cause hypotension

Question 6

What distinguishes levonordefrin from epi?

Answer 6

• lower systemic toxicity
• acts primarily at alpha receptors
• maximal dosage without systemic problems is 1 mg
• Epi 50% blocks alpha activity and 50% beta activity
• Levonordefrin is 75% alpha receptors and 25% beta

Question 7

What is Epinephrine FDA classification?

Answer 7

FDA Class C because it crosses the placenta. Lingual hernias were found to be significant in pregnant women studies

Question 8

What are some drug interactions of concern?

Answer 8

• Beta-adrenergic blocking agents
• arrhythmia
• antianginal effects
• ad hypertensive crises

Question 9

What are the drug complications of vasoconstrictors with None selective beta blockers?

Answer 9

Hypertensive and cardiac reactions

Question 10

Vasoconstrictors with tricyclic antidepressants

Answer 10

• Hypertensive and cardiac reactions