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What is drug excretion?
What is drug excretion?
Drug and/or drug metabolites excreted in urine, faeces or bile. Drug metabolites rendered polar (and water soluble) by phase II metabolism are not reabsorbed, thus excreted in the urine.
What are the three processes of drug excretion?
What are the three processes of drug excretion?
- Glomerular filtration
- Active tubular secretion
- Passive reabsorption by diffusion across the tubular epithelium
What is drug clearance? Why is it important?
What is drug clearance? Why is it important?
- Clearance (CL) is an expression of the elimination of a drug from the body.
- CL is the volume of blood removed (or cleared) of drug per unit of time (e.g., L/hour or mL/minute)
- CL is important as it helps determine the dosage rate needed to maintain a desired [D]plasma
How can drug clearance be broken down in different categories?
How can drug clearance be broken down in different categories?
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What is the formula to estimate drug clearance in a flow parameter?
What is the formula to estimate drug clearance in a flow parameter?
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What is the relationship between drug plasma concentration and rate of elimination?
What is the relationship between drug plasma concentration and rate of elimination?
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How do you estimate Rate of elimination in terms of drug plasma concentration?
How do you estimate Rate of elimination in terms of drug plasma concentration?
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What is the difference between zero order and first order kinetics?
What is the difference between zero order and first order kinetics?
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What happens in a steady state in drug elimination?
What happens in a steady state in drug elimination?
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What is the dosage rate in this scenario?
Patient has COPD and is to be administered IV theophylline.
-Recommended [Drug]plasma is 10-20 mg/L.
-CL for theophylline is 3L/hour.
-Upper plasma limit is recommended for this patient
What is the dosage rate in this scenario? Patient has COPD and is to be administered IV theophylline. -Recommended [Drug]plasma is 10-20 mg/L. -CL for theophylline is 3L/hour. -Upper plasma limit is recommended for this patient
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What if we were calculating dosage rate in a different route of administration?
What if we were calculating dosage rate in a different route of administration?
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What is elimination half life? Why is it important?
What is elimination half life? Why is it important?
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How do we estimate elimination half life?
How do we estimate elimination half life?
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What is the elimination half life to reach steady state? Give an example by calculating it.
What is the elimination half life to reach steady state? Give an example by calculating it.
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How long would it take an IV infusion to wash out after it has been removed?
How long would it take an IV infusion to wash out after it has been removed?
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What are the factors determining elimination half life in a person? Use the equation to predict the effects.
What are the factors determining elimination half life in a person? Use the equation to predict the effects.
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What is glomerular filtration of drugs?
What is glomerular filtration of drugs?
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What is the role of tubular secretion of drugs in excretion?
What is the role of tubular secretion of drugs in excretion?
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What is the role of tubular reabsorption in excretion?
What is the role of tubular reabsorption in excretion?
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What are the factors affecting tubular reabsorption in drug excretion?
What are the factors affecting tubular reabsorption in drug excretion?
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