Pharmacokinetics Flashcards
Name the four pharmacokinetic properties that determine the onset, intensity, and duration of drug action.
Absorption, distribution, metabolism, elimination
Absorption
Transfer from site of administration to blood ex) mouth to blood
Distribution
Transfer from blood to tissue and target sites ex) blood to pancreas
What determines the rate of a drug response?
Absorption rates and distribution rates
Pros and cons of IV administration
Pros: Can have immediate effects, ideal if dosed in large volumes, suitable for irritating substances and complex mixtures, valuable in emergency situations, dosage titration permissible, ideal, for high molecular weight proteins and peptide drugs
Cons: unsuitable for oily substances, bonus injection may result in adverse effects, most substances must be slowly injected, strict aseptic techniques needed
What are the routes of administration for drugs?
Oral, Intravenous, Subcutaneous, Intramuscular, Transdermal (patch), Rectal, Inhalation, Sublingual
Each route has distinct characteristics affecting drug absorption and efficacy.
What is the absorption pattern for oral administration?
Variable; affected by many factors
Factors may include food intake, drug formulation, and individual patient characteristics.
What are the advantages of oral administration?
- Safest and most common
- Convenient and economical
- Absorption not required
- Can have immediate effects
- Ideal if dosed in large volumes
- Suitable for irritating substances
- Valuable in emergency situations
- Dosage titration permissible
Oral administration is often preferred due to its ease of use.
What are the disadvantages of oral administration?
- Limited absorption of some drugs
- Food may affect absorption
- Patient compliance is necessary
- Drugs may be metabolized before systemic absorption
- Unsuitable for oily substances
These factors can limit the effectiveness of oral medications.
What is a key advantage of intravenous administration?
Bypasses the first-pass effect
This allows for higher bioavailability of drugs that are poorly absorbed orally.
What are the advantages of subcutaneous administration?
- Slow and sustained absorption
- Suitable for oily vehicles and certain irritating substances
- Preferable to intravenous if patient must self-administer
This method allows for gradual release of medication.
What is a disadvantage of intramuscular administration?
Can cause intramuscular hemorrhage
This risk is particularly relevant during anticoagulation therapy.
Fill in the blank: The _______ administration allows for localized effects to target lungs.
Inhalation
Inhalation administration is effective for respiratory problems.
What are the disadvantages of inhalation administration?
- Limited to certain types of drugs
- Some patients may have difficulty using inhalers
- May lose part of the drug dose if swallowed
These limitations can affect the overall efficacy of inhaled medications.
What is a key advantage of transdermal administration?
Convenient and painless
Transdermal patches are often used for continuous delivery of medication.
