Exam

Question 1

Bioavailability

Answer 1

Amount of drug present in the body that reaches the systemic circulation unchanged

I.e IV = 100%

Question 2

First Pass Metabolism

Answer 2

The amount of drug lost though Gastrointestinal Transit due to large surface area for absorption before it reaches systemic circulation

Question 3

Pharmacokinetics

Answer 3

What the body does to the drug in the process of ADME, This includes the process of drug through , into and out of the body

Question 4

Pharmacodynamics

Answer 4

What the drug does to the body and the mechanism of action

Question 5

Free drug

Answer 5

A drug unchanged not bound to a protein

Question 6

Water soluble

Answer 6

Has difficulty crossing the cell membrane so remains in circulation so not as well distributed, so rapidly cleared by the liver and kidneys

Question 7

Lipid Soluble

Answer 7

Easier to cross cell membrane distribution is more widespread and elimination/excretion is slower but absorption is higher as is distribution

Question 8

Distribution

Answer 8

How a drug is dispersed or disseminated around the body to get to its site of action.
The amount of drug in the body - how widely a drug is distributed in body tissue.
Into body fluids, tissues, organs or protein bound

Question 9

Half Life

Answer 9

The amount of time it takes a drug to reduce by 50% in the body

Question 10

Steady State

Answer 10

When there is the same amount of drug entering the body as being eliminted

Question 11

Metabolism

Answer 11

How the body breaks down a drug into its component parts for activation, elimination or excretion.
Reduces drug activity, creates metabolites or activates a drug such as a prodrug as a metabolite

Question 12

Renal Excretion

Answer 12

The process or removing a drug from the body via the kidneys after being metabolised by the liver into a water soluble state

Question 13

EGFR

Answer 13

A measure of how well the kidney are working/filtration via the Glomerulus and Bowman’s capsule. Identified via a blood test and calculated taking into account : ethnicity, sex and age

Question 14

Enterohepatic recirculation

Answer 14

When a drug is excreted in the bile, and then re absorbed into the intestines/gut and transported back to the liver by the hepatic portal

Question 15

Type A drug reaction

Answer 15

Augmented drug reaction , usually dose dependant, likely predictable and can be anticipated as part of a side effect or normal drug reaction

Question 16

Type B drug Reaction

Answer 16

Bizzare and non predictable, not dose related and likely related to the individual response

Question 17

Absorption

Answer 17

The movement of the drug into blood circulation.
The process of the drug moving from site of administration to the systemic circulation - diffusion facilitated by movement from an area of high concentration into an area of low concentration by active and passive transport

Question 18

Excretion

Answer 18

The process of removal of a drug from the body as a metabolite or unchanged drug

Question 19

8 Modes of excretion

Answer 19

1. Bile
2. Tears
3. Breast milk
4. Saliva
5. Renal
6. Faecal
7. Respiration
8. Perspiration

Question 20

BNF ADR’s in the Elderly

Answer 20

1. Constipation
2. Confusion
3. Hypotension
4. Falls

Question 21

Drug Affinity

Answer 21

How well a drug binds to a receptor

Question 22

Therapeutic Index /Window

Answer 22

The range of dose at which a drug is effective without unacceptable adverse reaction/events
I.e. the window of a dose between ineffective or toxic

Question 23

Agonist

Answer 23

Binds to a receptor to create, illicit or active a response

Question 24

Antagonist

Answer 24

Binds to a receptor to block, prevent or stops a response

Question 25

Cytochrome P450

Answer 25

A Hemoprotein that plays a key role in the metabolism of drugs in the liver, more than 50 enzymes in this class, with 6 main active to metabolise approx. 90% of known drugs

Question 26

Albumin

Answer 26

Is a transport protein in drug circulation

Question 27

Ligand

Answer 27

Is a protein molecule that binds to a receptor , can be a hormone, a neurotransmitter or a chemical from a pharmaceutical drug

Question 28

What is a prescribing error

Answer 28

Can occur at any stage of teh prescribing process including: Prescribing Administering, preparing, dispensing, monitoring and reviewing or upon providing advice about a drug

Question 29

Topical Administration

Answer 29

For higher absorption at site reducing amount of drug else where in the body

Question 30

Transdermal administration

Answer 30

Used to prolong the administration of a drug via the skin

Question 31

Factors affecting absorption

Answer 31

Physiological: Renal & hepatic impairment Blood flow Surface area Site of administration and contact time Chemical: Lipid/water soluble Ion Channels and degree of ionisation Chemical stability

Question 32

Factors affecting distribution

Answer 32

Renal and hepatic impairment Blood flow/circulation/barriers Solubility Amount of drug bound to proteins Muscle and a tissue mass Obesity and oedema

Question 33

Pro Drug

Answer 33

A drug that needs to be metabolised to become active

Question 34

Targets for drug blinding

Answer 34

Ion channels Receptors Enzymes

Question 35

Receptors

Answer 35

Is a glycoprotein in cell membrane that bind to ligands

Question 36

Specificity

Answer 36

When a drug binds to a specific receptor

Question 37

Ion Channels

Answer 37

aids movement between cell membranes though ionisation Eg channel blockers or channel modulators in order to block or open the flow

Question 38

Drug interaction

Answer 38

When a drug encounter another natural or unnaturally occurring chemical that alters the intended action of a drug

Question 39

Enteral routes of administration

Answer 39

1. Oral 2. Sublingual 3. Rectal 4. PEG/NG

Question 40

Parenteral Routes of Administration

Answer 40

1. IV 2. IM 3. SC 4. Topical/Transdermal

Question 41

Blood Brain Barrier

Answer 41

In place to prevent toxic substances from reaching the brain or progressing through the placenta in pregnancy. Crossing is usually by passive diffusion in small molecules that dissolve into lipid membranes

Question 42

Three Key distribution Pathways

Answer 42

1. Protein Bound - takes longer to excrete 2. Into body Fluids - is quicker to excrete as water soluble 3. Into tissues and organs - free drug have a higher bioavailability

Question 43

Factors affecting Plasma Protein levels

Answer 43

Can be affected by Hepatic Impairmet due to less albumin being made reducing amount of protein. Muscle wasting diseases can affect this In ITU proteins and albumin can be replaced . Patients with reduced Plasma proteins will require dose adjustment to prevent toxicity from increased free drug levels

Question 44

Phase 1 Metabolism

Answer 44

Modification : Reduction, Oxidisation or hydrolysis reactions converts lipophilic drugs into polar molecules

Question 45

Phase 2 metabolism

Answer 45

Conjugation: By coupling a drug and/or its metabolites to another molecule in order to make it water soluble

Question 46

Enzyme Inhibitors

Answer 46

Reacts with Enzymes to reduce/stop a reaction

Question 47

Enzymes Inducer

Answer 47

Increases metabolic activity by binding and activating it

Question 48

Competitive Antagonist

Answer 48

Binds to the same site as a agonist blocking its action E.g. Naloxone

Question 49

Irreversible Antagonist

Answer 49

An antagonist that binds permanently to a receptor until the cell produces a new receptor

Question 50

Carrier ION

Answer 50

Helps move IONS between lipophilic and hydrophilic mediums to permeate membranes