Biotransformation and Metabolism Pathways — Flashcards

Flashcard 1: Oxcarbazepine _____ cause auto-induction of metabolizing enzymes.

Answer: does not (does/does not)

Flashcard 2: Phenytoin follows _____-order kinetics at lower concentrations. As the concentration increases, the elimination changes to zero-order kinetics.

Answer: first

Flashcard 3: Nonbenzodiazepine hypnotics have a _____ duration of action due to rapid metabolism by the liver

Answer: short

Flashcard 4: If a drug has _____ renal clearance than GFR, then drug is secreted in renal tubules.

Answer: more::more/less

Flashcard 5: Which protease inhibitor undergoes metabolism by CYP2C19 instead of CYP3A4?_____

Answer: Nelfinavir

Flashcard 6: Succinylcholine and mivacurium are metabolized by the enzyme _____

Answer: pseudocholinesterase

Flashcard 7: All barbiturates (thiopentone, thiamylal, methohexital) other than _____ are metabolized by liver

Answer: phenobarbitone

Flashcard 8: What formula is used to calculate **loading dose**?

Answer: Loading Dose = $\frac{C_p \times V_d}{F}$

Extra: $C_p$ = target plasma concentration $V_d$ = volume of distribution $F$ = bioavailability

Flashcard 9: What is the formula for half-life (t1/2) in first-order elimination kinetics?

Answer: t1/2 = (0.693 × Vd) / CL

Extra: Where: - Vd = Volume of distribution - CL = Clearance Note: In first-order kinetics, the half-life is constant regardless of the plasma concentration.

Flashcard 10: What is the formula for Volume of Distribution (Vd)?

Answer: Vd = Amount of drug in the body / Plasma drug concentration (Cp)