Week 4 - Basic Principles of Pharmacology II Flashcards
What happens when drugs interact?
Increased effects
Decreased effects
Unexpected effects (new problems)
How do drugs interact?
Mixing problem?
Do not mix well physically or chemically
How do drugs interact?
Body handling changes?
one can change how the body - absorbs, distributes, breaks down, gets rid of
changing its level in the body
How do drugs interact?
Action site?
can interfere with each other directly where they work in the body
How do drugs interact?
Shared toxicities?
similar harmful effects on the same organ
Clinical Significance - Why are drug interactions important?
- Common in hospital
- Dangerous for some drugs (narrow therapeutic range)
- Hard to predict (can cause unusual symptoms)
- major cause of errors
How to minimize interactions?
1 - know your patients drugs
2. use fewer drugs when possible
3. be aware of risky drugs (which ones most likely to interact)
4. Time drugs right (with or w/o food, specific times)
5. Adjust dosages -
6. watch for problems
7. educate patients
How does food alter drug absorption?
Increase absorption
or
Decrease absorption
How does food alter delayed onset?
Food slows decreasing drug absorption
Takes longer to start working and reaching its peak
How does food alter drug metabolism?
Grapejuice effect (inhibits metabolism of many drugs in intestine and increases levels in bloodstream
Other food drug interactions
How does food alter drug toxicity?
increases toxicity
Adverse drug reactions.
Side effect …
produced at therapeutic doses
Adverse drug reactions.
Toxicity
Excessive dosing
Adverse drug reactions.
Allergic Reaction
immune response
Adverse drug reactions.
Idiosyncratic Reaction
Uncommon drug response due to genetics
Adverse drug reactions.
Iatrogenic disease
a disease caused by a drug
Adverse drug reactions.
Carcinogenic Effect
Causes cancer
Adverse drug reactions.
Teratogenic Effort
causes birthdefects
Organ Specific Toxicity -
Hepatotoxic Drugs
damage liver
Organ Specific Toxicity -
QT interval drugs
prolong the QT interval on EKG
Increases risk of dysrrhythmia
Organ Specific Toxicity -
Organ toxicity
Damages:
kidneys
bone marrow
ears
Variations that affect drug responses…
Bodyweight and composition
Surface Area
Variations that affect drug responses…
Individual Pathophysiology
kidney disease
liver disease
Variations that affect drug responses…
Tolerance. (to the drug)
decreased response
Pharmacodynamic tolerance -
