Pharmacokinetics Flashcards
What are the 3 major routes of drug administration?
Enteral
Parenteral
Topical
What are the 3 delivery methods of Enteral administration?
- Oral
- Sublingual
- Buccal
What is a chemical envelope that protects the drug from stomach acid, delivering it instead to the less acidic intestine, where the coating dissolves and releases the drug?
Enteric-coated preparations
What kind of drugs is enteric-coating useful for?
Acid-unstable drugs
What medications have special coatings or ingredients that control the drug release, thereby allowing for slower absorption and a prolonged duration of action?
Extended-release medications
What kind of drugs is parenteral administration used for?
poorly absorbed drugs
drugs that are unstable in the GI tract
unable to take oral medications
True or False: Parenteral administration has the highest bioavailability
True
What are the three major Parenteral routes?
- Intravascular
- Intramuscular
- Subcutaneous
What kind of route is effective for respiratory disorders (such as asthma and COPD), because the drug is delivered directly to the site of action, thereby minimizing systemic side effects?
Oral inhalation
How is intrathecal/intraventricular route administered?
directly into the CSF
How is transdermal route administered?
application of drugs to the skin
What advantage does the rectal route have on other routes?
preventing destruction of the drug in the GI environment.
What is the term known as the transfer of a drug from the site of administration to the bloodstream?
Absorption
What does the rate and extent of absorption depend on?
- environment where the drug is absorbed
- chemical characteristics of the drug
- route of administration
Which type of mechanism of absorption do drugs mostly use?
Passive diffusion
Which mechanism of absorption is used to transport drugs of exceptionally large size across the cell membrane?
Endo/Exocytosis
Which mechanism of absorption is Vitamin B12 used with?
Neurotransmitters such as NE?
Vitamin B12: Endocytosis
Norepinephrine: Exocytosis
True or False: A drug passes through membranes more readily if it is uncharged.
True
True or False: the lower the pKa, the more acidic the drug is.
True
What is the transmembrane transporter protein responsible for transporting various molecules, including drugs, across cell membranes
P-Glycoprotein