Week 1 Flashcards
(20 cards)
the amt of drug leftover (after 1st pass affect) to be distributed throughout the body
bioavailability
What are some factors that affect distribution of a drug by affecting BLOOD FLOW?
Abscesses, exudates, glands, & tumors decrease distribution
what are risks of hypoalbumeria and who many have hypoalbumeria?
excess free drug, can cause toxicity.
Sick patients who are acutely ill (often albumin levels go down with immunity)
only free (unbound) drugs are _____ drugs
ACTIVE
factors affecting drug distribution?
- Protein binding
- Blood flow (Abscesses, exudates, glands, & tumors decrease distribution)
- Body tissue affinity (can create potential toxicities within that tissue, or it can slowly release back into the blood stream. Ex: amiodarone (antiarrhythmic))
what is drug metabolism
the process by which the body inactivates or biotransforms drugs
Mostly, drugs are inactivated by ________and are then converted or transformed by ___________
liver enzymes
hepatic enzymes
where is the primary site for drug metabolism?
liver
When the liver enzymes are elevated, what does it indicate?
an injury to the liver
An increase in bilirubin is indicative of…?
an injury to the liver
how can liver diseases affect metabolism?
Liver diseases can affect metabolism (e.g., hepatitis, cirrhosis) by inhibiting the drug-metabolizing enzymes in the liver (risk of toxicity)
what is half life
Time it takes for ½ drug concentration to be eliminated
gives you an idea of how frequently you should be giving the drugs
How many half lives does it take to reach a steady state?
3 to 5 half lives
what is the main route of drug excretion in the body?
kidneys
What is the most accurate lab value to indicate kidney function?
serum creatinine (take the test in the morning, and then re-draw 12 hours later) Gives a great snapshot of what's happening with the kidneys at that point in time
Other excretion routes (besides the kidneys) where drug excretion occurs is:
Liver, bile, feces, lungs, saliva, sweat, & breast milk
what is a normal range of creatinine clearance value?
Normal is 85 to 135 ml/min
What types of drugs are excreted by the kidneys?
Kidneys filter out free unbound drugs, water-soluble drugs and unchanged drugs.
(Protein bound drugs can’t be excreted via the kidneys)
What is creatinine?
the metabolic byproduct of muscle tissue that is excreted by kidneys
(Less muscle mass = lower values (women & elderly)
How are protein-bound drugs excreted from the body?
they aren’t!
