Lecture 4 Flashcards
What are pharmacokinetics and pharmacodynamics?
- PKinetics = what the body does to the drug.
- PDynamics: What the drug does to the body.
Dynamics = drug effect on body.
What 5 factors affect drug absorption?
- Altering stomach pH
- Inc/dec GI motility
- Mucosal damage
- Preventing absorption
- Reducing active transport mechanisms
What factors affect distribution of a drug?
- Increased adipose tissue
- Low total-body water content
- Decreased serum albumin
What factors affect metabolism of a drug?
- Reduced hepatic blood flow and liver size
- Use of a P450 inhibitor/inducer drug.
What factors affect excretion of a drug?
- Decreased renal tubular function
- Decreased GFR
What is polypharmacy?
Usage of multiple drugs to treat a single condition, often >5 drugs.
What are adverse reactions usually most related to the use of?
- Multiple medications
- Number of chronic illnesses present
How many hospitalizations occur each year in elderly patients?
14 million
What 2 medication classes are responsible for 2/3 of all medication related hospitalizations?
- Anticoagulants
- Hyperglycemics (Insulin)
What is the difference between an adverse drug reaction vs an event?
- Reaction = UNWANTED effect at normal dosage and use.
- Event = Injury/harm from use of a drug
Examples of ADRs: Bradycardia leading to syncope from BB use.
Diarrhea 2/2 abx use
Bleeding associated with anticoagulants.
What is the most common type of drug-drug interaction (DDI)?
P450 INHIBITION
2nd is P450 Induction.
What is a common drug that is used for HLD and is metabolized by P450?
Statins
Results in rhabdo if inhibited!!!
Why do BBs potentially cause an drug-disease interaction in COPD patients?
Underlying disease increases susceptibility to beta blockade, which could worsen their COPD.
How much does having additional providers increase ADR likelihood in poly-provider syndrome?
29% for every additional provider.
E-prescribing drugs is preferred, and only to one pharmacy!
What should we keep in mind regarding serum creatinine levels in elderly patients?
Older patients have less muscle mass and therefore produce less creatinine.