Considerations In Drug Therapy

Front 1

Pharmacokinetics

Back 1

"what the body does to the drug"

Front 2

Pharmacodynamics

Back 2

"what the drug does to the body"

Front 3

Drug receptors

Back 3

May be enzymes, cellular mediators, proteins or other structures on organs or membranes. Pharmacodynamics is linked to pharmacokinetics by the the drug receptor complex theory. Intensity of pharmacologic effect is related in part to the concentration of the drug gaining access to drug receptors.

Front 4

Therapeutic range

Back 4

somewhere between the MEC and the MSC depending on the pt

Front 5

monitoring parameter

Back 5

Drug efficacy and drug toxicity can only be determined from direct clinical assessment ofthe patients drug response. This is why it is imp to define these.

Front 6

bioavailability

Back 6

Is a term which describes the extent of drug entry into the systemic circulation and is defined in reference to direct IV drug administration, where the extend of the drug is considered to be 100%.

Front 7

volume of distribution

Back 7

The extent of drug distrubution is based upon the degree to which the drugs distribute beyond the serum or plasma. Drugs with a large volume distrubute extensively into extravascular tissuesand those with a small volume of distribution do not.

Front 8

first-pass effect

Back 8

related to the strategic location of the liver in the venous portal pathway between the gut and system circulation. Drugs given orally and well absorbed in the gut must first pass throug hthe liver before entering into arterial circulation. When the liver has a high affinity and high metabolizing capacity for a drug, it may remove and metabolize substantial amounts of the drugs during the first pass. The first pass is so effective for some drugs that they cannot be administered the oral route

Front 9

elimination of half life

Back 9

Drug elimination facotr. half life is defined as the time required for the drug level to decline by 50%. The half life is important in decisions about proper dosing intervals for medications.

Front 10

steady state concentration

Back 10

When drugs are administered, the drug level in the body will gradually increase to a stable value, the average strady state, when the rate of drug entry equals the rate of drug elimination.

Imp. Concept: A drug approaches steady state after 4-5 half lives of the drug in question, and when a drug is no longer administered, it takes approximately 4-5 half lives for the drug to be eliminated from the body.

Front 11

cytochrome P450

Back 11

is a generic name for the group of enzymes that are responsible for most drug metabolism reactions

Front 12

Drug delivery system

Back 12

formulation or device that safely brings a therapeutic agent to a specific body site at a certain rate to achieve an effective concentration at the site of drug action

Front 13

pro drug

Back 13

is form of drug that remains inactive during its delivery across biologic membranes or until it reaches the site of action

Front 14

blood brain barrier

Back 14

Functions:
1- protects the brain from foreign substances in the blood that may injure the brain

2-protects the brain from normal hormones and its of the rest of the body

3-it maintains a constant environment for the brain

Front 15

State the factors that determine the distributional properties of a drug?

Back 15

molecular size, lipophilicity, acid/base properties, affinity to bind to circulating and tissue proteins

Front 16

State the two ways that drug biotransformation may contribute to drug elimination

Back 16

1- Can convert a lipophilic substance to a water soluble form which is more readily excreted in urine or bile than is the original drug

2- Biotransformation to a pharmacologically inactive metabolite effectively eliminates the original drug from the system insofar as its pharmacodynamics are concerned

Front 17

Estimate the time it takes for a drug to reach steady state and to be eliminated from the body when the drug is discontinued when given the drugs half life

Back 17

A drug approaches steady state after 4-5 half lives of the drug, and when a drug is no longer administered, it takes approximately 4-5 half lives for the drug to be eliminated from the body

Front 18

List factors influencing drug effects in the body

Back 18

1- Pt factors - body size and composition, sex, age, and certain habits

2- diseases and concurrent therapy factors

3-Concurrent drug therapy

Front 19

Define linear and non-linear pharmacokinetics and indicte the likely pharmakinetics of a drug when given information about the relationship between dosing and the steady state serum concentration

Back 19

Linear - Most follow linear in which steady state serum concentrations change proportionally with long term daily dosing. If a drug follows linear pharmacokinetics, then a pt who doubles the dose of a medication will have a doubling of the steady state serum concentration of that drug.

Nonlinear- Instead of the steady state drug concentrations changing proportionally with the dose, serum concentration changes may be more or less than expected. i.e. if a practitioner doubles the dose of a drug the steady state serum concentration of the drug could quadruple with corresponding pharmacological effects and potentially toxicities too. dilatin.

Front 20

State the rational for advantages associated with targeted drug delivery systems and control-release drug delivery systems

Back 20

Targeted: to optimize drug's therapeutic index (ration of the therapeutic dose to the toxic dose) by strictly localizing its activity to the site or organ of action. Results in significant limiting of drug toxicity, reduction in the dose of the drug, and an increased efficacy of treatment.

Control Release: the release of a drug in a predesigned manner. Promotes therapeutic benefits while at the same time minimizing toxic effects. Reduces undesirable fluctuations of drug levels, enhancing therapeutic action and eliminating dangerous side effects.

Front 21

List drug considerations in pediatric and geriatric pts

Back 21

p 9

Front 22

State how health literacy impacts medication use and health outcomes

Back 22

p 10

Front 23

Provide several methods to address proper drug therapy in pts with limited health literacy

Back 23

p 10

Front 24

List the priniciples of rational drug therapy

Back 24

p 10