Clinical Pharmacokinetics

Question 1

Order of kinetics ?

Answer 1

1.First order -Exponential kinetics
2.Zero order -Saturation kinetics

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Question 2

First order kinetics Details ?

Answer 2

( Rates of ABSORPTION , Distribution, Metabolism , Excretion —- Proportion — Conc of the body )

Rate of metabolism(V) = Vmax x [C]/ Km x [C]

Michaelis-Menten kinetics

80mg——–40mg——-20mg———10mg————5mg—–2.5mg
50% excreted

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Question 3

Zero order kinetics ?

Answer 3

( Rates of ABSORPTION , Distribution, Metabolism , Excretion —- NOT (XXXXX)— Proportion — Conc of the body )

Rate of metabolism(V) = Vmax x [C]/ Km x [C]

A FIXED amount is metabolized

80mg—70mg—-60mg—–50mg———–
10mg=FIXED AMOUNT

Question 4

1ST ORDER drugs ?

Answer 4

1. low dose aspirine
2. low dose phenytoin
3. carbamazepine
4. phenobarbitone
5. paracetamol

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Question 5

Zero order drugs ?

Answer 5

1. high dose aspirine
2. high dose pheytoin
3. ethanol
4. warfarin
5. tolbtamide

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