Drug Excretion

Question 1

Renal excretion Equation ?

Answer 1

(Glomerular filtration + Tubular secretion) - Tubular Reabsorption

page-115

Question 2

Glomerular filtration factors ?

Answer 2

1. Molecular weight- <10000 dalton
2. Conc of drug in plasma
3. RBF(+) Drug excretion(+)
   4.GFR (+) Drug excretion(+)
   5.Neutral drug- rapidly filtered
   6.Plasma protein bindings—————
   NO

Only free drugs

but if bind to ALBUMIN its conc will be less than the total plasma conc

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Question 3

Tubular secretion factors ?

Answer 3

1. PCT — (Plasma to Lumen) =Drug

1.Acidic/Anionic transport protein
glycine sulphate glucoronic acid
penecillin probenecid

2.Basic/Cationic transport protein
morphine amiloraide histamine ethambutol cathecolamines thiazide frusemide digoxin

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Question 4

Tubular reabsorption ?

Answer 4

Lumen of DCT intoooooooooo the plasma

1.Lipid soluble drug=More reabsorbed
2.Water soluble drug = More excreted
3.acidic drug = acidic urine = more reabsorbed
4.alkaline drug = alkaline urine = more reabsorbed
5.acidic drug = alkaline urine = more excreted
6.alkaline drug = acidic urine = more excreted

Question 5

Imporatnce of Biliary Excretion >?

Answer 5

1.Due to ENTEROHEPATIC cycling= drugs which are in biliary route =Inc duration of drug action
2.Liver f= biliary excretion hampered = drug conc inc = toxicites

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Question 6

Prolongation of drug action ?

Answer 6

1. inc plasma protein binding
2. inc frequency
3. inc dose
4. inc absorption from the route of administration

5.dec rate of distribution
6.dec rate of metabolism
7.dec renal excretion
8.dec gut motility

118-119

Question 7

Drug excretion defination ?

Answer 7

it is the process by which drug or its metabolites are eliminated from the body

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Question 8

major route ? Kidney ?

Answer 8

all drugs except
frusemide and pathidine

Question 9

gastrointestinal excretion which drugs ?

Answer 9

antacid
BaSO4
Aminoglycoside

Question 10

hepatobiliary process excretion drug ?

Answer 10

anti-microbials
BDZ
tetracyclin
rifampicin
chloramphenicol
chlorpromazine

Question 11

skin excretion ?

Answer 11

V-C
Fe
griseoffulvin

Question 12

vagina excretion ?

Answer 12

metronidazole

Question 13

breast milk excretion ?

Answer 13

BDZ
morphine
phenobarbitone
penicillin
amphetamine
ampicillin
aspirin
folic acid
tetracycline

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Question 14

renal excretion of a drug can be inc by ?

Answer 14

acidic drug – urine alkaline
alkaline drug — urine acidic
diuretics use
intake of plenty of water
IV infusion of normal saline

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Question 14

tear excretion ?

Answer 14

rifampicin