Pharmacology Flashcards
(119 cards)
1
Q
Drug
A
An active substance with a direct effect in the diagnosis, cure, mitigation, treatment or prevention of disease
2
Q
Placebo
A
An inactive substance administered as though it’s a drug but which has no therapeutic effect
3
Q
Homeopathy
A
Giving patients medicines that contain little to no medicine
4
Q
Efficacy
A
How big is the max response
5
Q
Potency
A
How big a dose for the desired outcome
6
Q
Variability
A
The proportion of patients with desired outcomes
7
Q
Selectivity
A
How selective a drug is to its molecular target
8
Q
Safety
A
Proportion of patients with unwanted effects
9
Q
Bioavailability
A
How much of an administered drug will reach circulation
10
Q
Cost
A
How much does a course of it cost?
11
Q
Explain Lock and Key
A
Most drugs are chemically inert but bind transiently to command and control modules
12
Q
What is an agonist?
A
A drug that binds to a receptor to illicit a response
13
Q
What is a partial agonist?
A
An agonist that cannot produce a maximal response even when occupying all receptors
14
Q
How does a partial agonist act in the presence of a full agonist?
A
As a partial antagonist
15
Q
What is an antagonist
A
A drug that binds to a receptor but produces no response and blocks agonists from binding
16
Q
What does allosteric mean?
A
Relating to or changing the shape of a protein at a point other than the active site
17
Q
What is physiological antagonism?
A
Two drugs at different receptors causing opposing physiological actions
18
Q
What does label one show?
A
Superior Vena Cava
19
Q
What does label two show?
A
Pulmonary Artery
20
Q
What does label three show?
A
Pulmonary Vein
21
Q
What does label four show?
A
Inferior Vena Cava
22
Q
What does label five show?
A
Hepatic Vein
23
Q
What does label six show?
A
Hepatic Artery
24
Q
What does label seven show?
A
Hepatic Portal Vein
25
What does label eight show?
Renal Vein
26
What does label nine show?
Renal Artery
27
What does enteral mean?
Entering through the gut
28
What does suppository mean?
Entering through the rectum
29
What is a parenteral formulation?
An injectable drug
30
What does Lyophilized mean?
Freeze-dried
31
What is drug distribution?
The reversible transfer of a drug between the blood and extravascular tissue
32
Define Pharmacodynamics
What the drug does to the body
33
Define Pharmacokinetics
What the body does to the drug
34
Give the 6 main Parenteral routes
Subcutaneous, Intramuscular, Intravenous, Intraarterial, Intraosseous, Epidural
35
What does intraosseous mean? And what is the benefit of it?
Into bone marrow, non collapsible entry point to venous system
36
What is a topical formulation?
applied to the skin
37
Why do drugs need to dissolve to work?
To penetrate epithelial, endothelial and plasma membranes
38
What is ficks law?
Diffusion = ((Conc 1 - Conc 2) * area * Permeability) / Thickness
39
In a weak acid what will a PH increase cause?
Ionisation of target molecule
40
In a weak base what will decrease of PH cause?
Ionisation of target molecule
41
How do you calculate Bioavailability of oral drug from a Drug conc over time graph.
AUC (Oral) / AUC (IV) AUC = Area under curve
42
What is Bioavailability (F)?
Bioavailability (F) is the proportion of a drug that will reach circulation. It is between 1 and 0 and independent of dose.
43
How do you calculate Bioavailable dose?
Administered Dose * Bioavailability = Bioavailable Dose
44
What does Total body water include?
Blood volume + Interstitial volume + Intracellular volume
45
What does Extracellular volume include?
Blood volume + Interstitial Volume
46
What does Extravascular volume include?
Interstitial volume + Intracellular Volume
47
What is interstitial volume?
Fluid between cells
48
What is Intracellular volume?
Fluid within cells
49
What is typical blood volume?
5L
50
Define Bulk Flow
When a large amount of drug is injected into the bloodstream at once. It is distributed passively by passing through major organs.
51
What organs have good perfusion?
Liver, Lungs, Kidney, Brain, Heart
52
What organs have poor perfusion?
Fat, Bone, Muscle
53
What is Plasma protein binding?
When drugs bind to plasma protein so cannot cross membranes rendering them pharmacologically inactive.
54
What happens to plasma protein drug complexes when free plasma levels fall?
Bound drug is released from the complex
55
How do you calculate Volume of Distribution?
Vd = Drug dose / Plasma Conc
56
When can you not calculate Vd?
When drugs distributes unevenly
57
What is the blood brain barrier?
A collection of tight junction and astrocytes which prevent large / water soluble molecules entering the brain.
58
What is first pass metabolism?
When some oral drugs are metabolised before reaching circulation. This determines bioavailability.
59
Which organ does most metabolism?
The liver
60
Where is the CYP450 family of isozymes found?
Hepatocyte SER
61
What are the 2 stages of a conjunction reaction?
Inactivation and Solubilisation
62
What are the dangers of conjunction reactions?
May generate an active or toxic metabolite rather than an inactive one
63
What is a pro drug?
An inactive substance that is metabolised by the body after administration into an active drug
64
What drugs are excreted through the lungs?
Alcohol and inhaled anaesthetic
65
What molecules are excreted through biliary excretion?
Large metabolites (>500Da) and glucuronide conjugates
66
What are the 4 main stages of kidney excretion?
Throw away everything small, Take back anything still wanted, expel waste substances, excrete what is left
67
What is the afferent arteriole?
The arteriole that feeds blood into the glomerulus of the kidneys
68
What is the efferent arteriole
The arteriole that takes blood away from the glomerulus of the kidneys
69
What is Glomerular filtration?
The glomeruli passively filter 20 % of plasma on each pass, large molecules are not filtered into tubules, small molecules enter nephrons to be filtered
70
How do Lipophilic drugs pass through the kidneys?
Lipophilic drugs are able to diffuse back into
| peritubular capillaries so are reabsorbed
71
How do some drug interactions effect absorption?
Some drugs can neutralise stomach PH which can alter gut motility.
72
How do some drug interactions effect distribution?
Drugs may compete for binding to plasma protein which will increase free concentrations.
73
How do some drug interactions effect Metabolism through induction?
Some drugs can increase gene expression of enzymes that metabolise it, drugs that are metabolised by the same enzyme will be metabolised quicker
74
How do some drug interactions effect metabolism through inhibition?
When a metabolic pathway cannot metabolise 2 drugs at the same rate as when they are alone.
75
How do some drug interactions effect excretion?
Drug excretion can be affected by PH in
| kidney tubules
76
What is zero order elimination?
When a drug is eliminated at a constant rate
77
What is first order elimination?
When a proportion of a drug is eliminated per unit of time
78
What is Clearance?
The volume of blood from which the drug is cleared per unit of time.
79
What is continuous drug dosing?
a constant IV infusion which results in a steady state
80
what is a steady state?
When Plasma Conc (CPs) is constant
81
What is maintenance dosing?
When drugs are given at intervals to maintain an average Plasma Conc
82
What are loading doses?
A large first dose may be given to fill up the bodys Vd. This is followed by standard maintenance dosing or infusion.
83
How do you measure steady state?
Measured in half lives. The empty Vd will halve every half life.
84
What is the equation for Continuous IV infusion Rate of admin?
Rate of Admin = Rate of Elim = Clearance * CPss
85
What is the equation for Maintenance dosing??
(Dose * Bioavailability) / Dose interval = Cl * CPss
86
What is the equation for Loading Doses?
Loading dose * Bioavailability = Vd * CPss
87
What are the 3 branches of the ANS
Sympathetic NS, Parasympathetic NS and Enteric
88
Where are ganglions located in the Sympathetic NS
Towards the Spinal cord
89
Where are ganglions located in the parasympathetic NS
Towards the organ
90
How can the Sympathetic NS stimulate multiple organs at once
It can stimulate many post ganglionic neurons at once from the thoracic CNS region
91
What response does the Sympathetic NS create?
Fight or Flight
92
What response does the Parasympathetic NS create?
Rest and Digest
93
What neurotransmitters are used at Ganglions?
Acetylcholine
94
What receptors are used at the Ganglions?
Nicotinic recpetors (N1)
95
How many subunits make up a Nicotinic receptor?
5
96
How many ACh must bind to a Nicotinic receptor to open it?
2 ACh
97
Where are N2 receptors found
N2 (NM) are found at skeletal muscle junctions in the Som NS
98
What neurotransmitter is used at Parasympathetic NS post ganglionic nerves?
Acetylcholine
99
What receptors are used at Parasympathetic NS post ganglionic nerves on the target tissue?
Muscarinic AChR
100
What type of receptor is a Muscarinic AChR?
G-Protein coupled recpetor
101
What happens when ACh binds to a muscarinic AChR?
Ga protein will swap GDP for GTP. The Ga protein will dissociate and activate a downstream effector muscle.
102
What neurotransmitter do MOST Sympathetic NS post ganglionic nerves use?
Noradrenaline
103
What Receptor do MOST Sympathetic NS post ganglionic nerves use?
Adrenal receptors
104
What neurotransmitters and receptors do Sympathetic NS post ganglionic sweat gland nerves use?
Acetylcholine and Muscarinic receptors
105
What neurotransmitters and receptors do Sympathetic NS Adrenal medulla nerves use?
Acetylcholine and Nicotinic receptors
106
How do Adrenal medulla pathways differ to other Sympathetic NS pathways?
No ganglions on pathway
107
How do neurotransmitters re-enter the pre-synaptic vesicle.
Specific transporters for that neurotransmitter at reuptake sites
108
What is MAO and where is it found?
MAO (mono-amine oxidase) is a chemical that breaks down noradrenaline and is found in SNS pre synaptic neurons
109
How can a drug act as an agonist at a Muscarinic receptor?
Mimicking ACh and binding to M receptors
110
How can a drug act as an antagonist at a Muscarinic receptor?
Blocking ACh from binding to M receptors, this is often reversible but not always
111
How can you increase selectivity of Noradrenaline to Beta Adrenal receptors?
Adding groups to the N atom on Noradrenaline
112
What are the 2 types of Adrenoreceptors?
Alpha (a) and Beta (B)
113
Which Adrenoreceptor is Noradrenaline more effective towards?
a receptors
114
Which Adrenoreceptor is adrenaline more effective towards?
Effective against both but more selective to B receptors
115
Where are a1 adrenoreceptors found?
Blood vessels and Vascular smooth muscle
116
What does stimulation of a1 adrenoreceptors cause?
vasoconstriction which results in increase venous and arterial blood pressure
117
What do a2 receptors do and where are they found?
They are autoreceptors and prevent too much neurotransmitter being released. They are found on the pre-synaptic neuron
118
What do B1 adrenoreceptors do?
Increase HR and contraction force
119
What do B2 adrenoreceptors do?
Relax airways
