Drug Metabolism

Question 1

Phase I

Answer 1

Reduction, oxidation, hydrolysis, *(Cyt P450)

Yields slightly polar water soluble, still active (slightly)

Lose first in Geriatrics

Question 2

Phase II

Answer 2

Conjugation (Glucuronidation, Acetylation, Sulfanation)

Very polar and inactive metabolites (renally secreted)

Geritatrics have GAS (Glucuronidation, acetylation, sulfonation)

Question 3

Therapeutic index

Answer 3

TD50/ED50

Higher TI, more safe

Lower TI, more dangerous