Barbiturates: Chapter 5

Question 1

troduction of Thiopental (1934):

Answer 1

• Rapid-acting barbiturate.
• Enabled quick general anesthesia induction.
• Replaced slower, riskier diethyl ether induction.

Question 2

Thiopental’s Import/Export Issues:

Answer 2

• Previously imported from overseas.
• Export to U.S. stopped due to use in lethal injections.

Question 3

Current Relevance of Barbiturates:

Answer 3

• Possibility of resuming shipments.
• Still used by some anesthesiologists outside U.S.
• Serves as prototype for IV anesthetic comparison.

Question 4

Barbiturates Significance in Drug Development:

Answer 4

Essential for understanding newer IV anesthetics.
Propofol, etomidate, midazolam compared to barbiturates.

Question 5

Origin of Barbiturates:

Answer 5

Derived from barbituric acid.

Question 6

Substitutions on Barbiturates:

Answer 6

Affect properties and pharmacokinetics.
Influence potency and effects.

Question 7

Oxybarbiturates

Answer 7

Examples: Pentobarbital, secobarbital.
Contain oxygen at the second position.

Question 8

Thiobarbiturates:

Answer 8

Examples: Thiopental, thiamylal.
Sulfur replaces oxygen.
Greater lipid solubility and hypnotic potency.

Question 9

Phenyl Group Addition:

Answer 9

Example: Phenobarbital.
Increases anticonvulsant, not hypnotic potency

Question 10

Methyl Group on Nitrogen:

Answer 10

Example: Methohexital.
Heightens hypnotic potency.
Lowers seizure threshold.
Causes myoclonus during induction