Quiz 1: Drug-Herb Interactions Flashcards
Pharmacokinetics refers to?
What the body does to the drug after it is administered.
Pharmacodynamics refers to?
What the drug does to the body.
What is polypharmacy?
Where patients get multiple medications from one or more doctors.
Define ADME (Pharmacokinetic).
- Absorption: How the drug enters the bloodstream (e.g., through oral, intravenous, or inhalation routes).
- Distribution: How the drug spreads through the body to various tissues and organs.
- Metabolism: How the drug is broken down, usually in the liver, into metabolites that the body can use or eliminate.
- Excretion: How the drug and its metabolites leave the body (e.g., through urine, feces, or sweat).
Therapeutic index means?
Measurement of how safe the drug is. Larger number is more safe.
It’s a ratio between the toxic dose and the therapeutic dose.
Should a drug be hydrophilic or hydrophobic?
Hydrophobic or lipophilic because it can pass through the phospholipid bilayer to enter the cells by passive diffusion.
Protein binding: what is a class I drug and a class II drug?
Class I drugs are highly protein-bound, meaning a large proportion of the drug molecules bind to plasma proteins like albumin, leaving only a small amount of the drug in its free (active) form.
Class II drugs are extensively protein-bound, but their concentrations in the plasma are high enough that they saturate available protein-binding sites, leaving a significant amount of the drug in its free (active) form.
If a class I drug is administered with a class II drug, free drug levels of the class I drug will be less than or greater than anticipated?
Greater.
The bioavailability of an intravenous drug is ________%.
100%.
To maximize the drug availability, a drug needs to be primarily hydrophilic or hydrophobic?
Hydrophobic, but somewhat soluble in aqueous solutions.
4 factors that can affect bioavailability of a drug?
First-pass hepatic metabolism.
Drug solubility.
Chemical instability.
Chemico-physical properties of drug formulation.
True or false. A drug needs to be a weak acid or a weak base pH-wise to cross the cell membrane.
True!
Drugs enter the cell through three main mechanisms:
Passive diffusion.
Facilitated diffusion.
Active transport.
Oral drugs can be absorbed where? which is the most common site of absorption due to its vast surface area.
Stomach through the duodenum.
What kind of drug administration?
Oral
Sublingual blood
Rectal
Enteral administration.
What kind of drug administration?
Intravenous injection.
Subcutaneous injection.
Intramuscular injection.
Intraarterial administration.
Intrathecal injection.
Parenteral administration.
Other routes of administration?
Oral inhalation.
Intranasal.
Topical.
Transdermal.
4 main factors that affect drug distribution?
Blood flow.
Capillary permeability.
Drug structure.
Degree of binding to proteins.
True or false? Large drugs cannot escape plasma. Small drugs can leave plasma.
True.
What is phase I and phase II of drug metabolism?
Phase I: reactions convert lipophilic drugs into water soluble or polar molecules.
Phase II: conjugation (adding a molecule) of a drug to make drug more hydrophilic to achieve kidney metabolism.
Statin drugs are a class of medications primarily used to lower cholesterol levels in the blood. Clients taking statin drugs can’t have?
Grapefruit juice.
The most common route of drug elimination is?
Kidneys.
Steady state has been achieved when?
The drug input rate equals the drug elimination rate.
How many half-lives for drugs to reach steady state?
4 to 5 half lives.
Define tachyphilaxis.
Rapid and short-term onset of drug tolerance.
One of the largest contributing factors for drug potency is?
The affinity of the drug for the receptor.
Drug efficacy is dependent on?
The number of drug-receptor complexes formed.
Define therapeutic index:
Measurement of how safe a drug is. Ratio between the toxic dose and the therapeutic dose. Larger number is more safe drug.
Is a solid or a liquid drug more easily absorbed?
Liquid is very easy to absorb. A solid drug absorbing will depend on the size of the molecule.
Is highly concentrated drug easy or hard to pass the cell membrane.
Difficult absorption. Highly concentrated drugs are typically advised to be diluted.
To achieve a drug steady state, is a single-fixed dose or repeated-fixed dose more important?
Repeated-fixed dose.
Define loading dose.
Higher dose administered at treatment initiation.
