Psychopharm Lecture 2

Front 1

Effects of a drug depends on what?

Back 1

dosage

Front 2

Patients commonly think what is related to strength?

Back 2

numerical dosage

Front 3

dosage: qD

Back 3

quaque die – one a day

Front 4

dosage: BID

Back 4

bis in die – twice a day

Front 5

dosage: TID

Back 5

ter in die – three time a day

Front 6

dosage: q#h

Back 6

– Quaque # hours – once every # hours

Front 7

What are risks with patients self-administration meds?

Back 7

- taking when symptomatic

- taking too much / too little

- giving to friends

- selling

Front 8

What questions to ask before prescribing medication?

Back 8

- What dose will be effective?

- What does will cause harm?

- How is medication absorbed/eliminated?

- How quickly does medication take effect?

Front 9

Researchers typically test the effect of drug on ___ before moving onto human

Back 9

animals

Front 10

ED50 stands for ___ ___ ___; Represents the specific dose of a given drug that is effective in 50% of the population

Back 10

effective dose value

Front 11

Different medications will have different ___

Back 11

ED50

Front 12

How is ED50 helpful?

Back 12

- Used to compare different medications and determine if a drug is more potent than another.- It can also help determine which drugs have a wider therapeutic range

Front 13

___: refers to the amount of a drug that produces a certain level of therapeutic effect

Back 13

Potency

Front 14

Drug X reaches its ED50 at 2.0 mg, when compared with Drug Y, which reaches its ED50 at 8.0 mg. This suggests that Drug X is ___ than Drug Y.

Back 14

stronger; more potent

Front 15

___ – Maximal effect a drug can produce regardless of the dosage prescribed

Back 15

Efficacy

Front 16

Taking more than approximately 3.0 mg of Drug X or 10.0 mg of Drug Y will not increase the drug’s effectiveness, as these or higher doses may place the individual at risk for experiencing adverse side effects, toxic doses, or even overdose. this is an example of ___?

Back 16

Efficacy

Front 17

potency and efficacy

Back 17

review

Front 18

x and y axis; closer to the left is more ___; closer to the sky, more ___

Back 18

potent; efficacy

Front 19

Drug ___ – with each subsequent dose of a medication a patient experiences INCREASED effective treatment outcomes without change medication dosage

Back 19

sensitization

Front 20

Drug ___ – with each subsequent dose of a medication a patient experiences a REDUCTION in treatment outcome without change in dosage

Back 20

tolerance

Front 21

___ (acronym) – dose at which a drug will cause a toxic effect in 50% of the population

Back 21

Toxic Dose – TD50

Front 22

It is important to know the relative difference between the average therapeutic dose and the average toxic dose. This is defined as the ___.

Back 22

Therapeutic Index (TI)

Front 23

How is TI calculated?The smaller the TI the ___ the risk

Back 23

TI = TD50/ED50; higher

Front 24

Drug safety lethality: For Drug Y the ED50 is 8mg and the TD50 is 10mgThe TI of Drug Y is 10/8 = 1.25This is a very small TI and thus Drug Y may be ___ to administer.

Back 24

risky; since it has less room for therapeutic improvement and may have more of a chance to produce a toxic or adverse drug effect with increases in dosage

Front 25

___ refers to how a substance travels through the body and brain by absorption, distribution, metabolism, and elimination.

Back 25

Pharmacokinetics

Front 26

Pharmacokinetics focuses on how the body ___ a drug

Back 26

effects

Front 27

___ of drug administration can effect the speed in which it is absorbed and distributed

Back 27

route

Front 28

___ - swallowing

Back 28

Oral

Front 29

___ – dissolving under the tongue

Back 29

sublingual

Front 30

___ – absorbing though the membranes of the nasal or oral cavities

Back 30

Nasal/mucosal membrane

Front 31

___ = breathing into the lungs

Back 31

inhalation

Front 32

___ - through the skin

Back 32

transdermal

Front 33

___ - injection under the skin

Back 33

subcutaneous

Front 34

___ - through the rectum

Back 34

intra-rectal

Front 35

___ - injection into the skeletal muscle

Back 35

intramuscular

Front 36

___ - jection into a major vein

Back 36

intravenous

Front 37

4 ways drugs cross membranes?

Back 37

Passive diffusionFacilitated diffusionActive transportEndocytosis

Front 38

___- proportion of a drug that enters circulation

Back 38

bioavailability

Front 39

Unless a drug is given IV the bioavailability will always be less than ___%; Medications will be metabolized and some portion of it will be ___ before reaching circulation

Back 39

100; eliminated

Front 40

___ is the movement of a drug throughout the body.

Back 40

distribution

Front 41

5 factors that affect distribution?

Back 41

Lipophilicity

Blood flow

Capillary permeability

Plasma and tissue binding

Volume of distribution

Front 42

___; - the more lipophilic the easier it passes through membranes___ some organs have more blood flow than others, areas with more blood flow will have a higher distribution of the substance (brain is more than skin)___ ___ - how leaky a capillary is, different organs are different (liver is more than brain)

___ and ___ binding- some drugs will bind to certain tissues more than others. Also some will bind to Albumin which is found in plasma, this will slow down distribution.___ -- ___- theoretical volume that drug needs to occupy to create a certain concentration in the plasma.

Back 42

LipophilicityBlood flowCapillary permeabilityPlasma and tissue bindingVolume of distribution

Front 43

____ describes the process by which a drug is altered chemically in the body into its metabolite, which may be more or less active.

Back 43

Metabolism

Front 44

Where does metabolism occur?

Back 44

Liver

Front 45

How many step process for metabolism?

Back 45

2 step

Front 46

Phase 1 of metabolism makes the drug chemical more ___. This is accomplished mostly by using the ___ ___ system.

Back 46

reactive; Cytohrome P450

Front 47

The cytochrome P450 system is important because other medications can ___ or ___ this system.

Back 47

speed; slow

Front 48

Metabolism: Phase 2- The 'activated' drug molecule is combined with another molecule to produce an ___ compound which is usually more water soluble making it easier for ___.

Back 48

inactive; excretion

Front 49

___ is the process by which a drug or its metabolite is removed from the body.

Back 49

Elimination

Front 50

4 places elimination can occur?

Back 50

This usually occurs in the kidneys (urine) but it can also take place through the gastrointestinal tract (feces) , the skin (sweat) or lungs (exhaled air).

Front 51

____- amount of time it takes to decrease plasma concentration of a drug by half

Back 51

Half Life (t1/2)

Front 52

Half-life tells us about the ___ of action of a drug

Back 52

duration

Front 53

How many half-lives to eliminate a drug completely?

Back 53

4 to 5

Front 54

Taking a 100 mg dose of an oral medication with a half-life of 15 minutes, the following is true:15 minutes after the drug administration, ___ of the drug remains in the body. (__% eliminated)30 minutes after the drug administration, __ mg of the drug remains in the body. (__% eliminated)45 minutes after the drug administration, __ mg of the drug remains in the body. (__% eliminated)1 hour after the drug administration, __ mg of the drug remains in the body. (__% eliminated)

Back 54

50; 50% / 25; 75% / 12.5; 87.5% / 6.25; / 93.75%

Front 55

Elimination: When drug doses are repeatedly administered the drug will accumulate in the body until it reaches a point where the rate of administration is equal to the rate of elimination. This is called ___ ___.

Back 55

Steady State

Front 56

How long to reach steady state? This is important because when prescribing a drug you want the plasma concentration to be effective and not toxic. You want the steady state of the drug to be in therapeutic range.

Back 56

4 - 5 half-lives.

Front 57

___ is defined as the study of the time course and intensity of the pharmacological effects of drugs

Back 57

Pharmacodynamics

Front 58

Pharmacodynamics focuses on how a drug ___ the body

Back 58

affects

Front 59

effects of pharmacodynamics are dependent on the ___ and ___ of exposure

Back 59

dose; route

Front 60

What three individual factors affect response to drug therapy?

Back 60

Genetics; Age; Gender

Hint 60

Genetics: People metabolize drugs differently based on their P450 enzymesAgeChildren: Still undergoing brain development, neural network connectivity and maturation. Weight less and are rapid metabolizers of substances, will therefore need smaller doses to avoid adverse effectsGeriatric: Physiological changes due to age as well as medical problems may lead to issues with the liver being able to metabolize drugs or the kidney being able to eliminate certain drugs. The heart may be too weak to circulate certain drugs to reach their target.Gender: Differences between men and women in regards to development, puberty, body composition all effect metabolism of drugs. Pregnancy has effect on this as well, and when women become pregnant.

Front 61

3 types of drug interactions?

Back 61

Canceling effectsSynergistic effectsParadoxical effects

Front 62

Drug-interactions that can happen w/ non-drug materials?

Back 62

Grapefruit juice; alcohol; herbal supplements

Hint 62

Grapefruit Juice: Mixing some heart medications with grapefruit juice may alter effectiveness of the medication ( interferes with metabolism)Herbal Supplements: Mixing St. John's Wort with SSRI medication can lead to Serotonin Syndrome which can be life threatening (additive effects of 2 drugs)Alcohol:19% of the population takes prescription drugs that interact with alcohol WHILE also drinking alcohol. Effects differ based on drug but can lead to organ failure

Front 63

Patients may also be ___ to specific substances within the drug such as excipients (the other stabilizing, bulking, or filling agents within a drug)

Back 63

allergic;

Front 64

Drug interactions: This can be problematic as it can lead to patients or health professionals misinterpreting an excipient's ___ effect to that of the prescribed medication

Back 64

adverse