Pharmacology Flashcards
1
Q
What are NSAID’s used for?
A
Inflammatory pain
2
Q
Which enzymes are blocked in non-specific NSAIDs?
A
COX1 and COX2
3
Q
Give 3 examples of non-specific NSAIDS,.
A
Ibuprofen, aspirin, naproxen
4
Q
What are specific NSAIDS?
A
They block COX2 enzymes
5
Q
Give an example of a specific NSAID?
A
Celecoxib
6
Q
What is the role of prostaglandins in pain pathways?
A
Prostaglandins are released where the damage has taken place. These bind to receptors and depolarise them in the first order neurones causing a signal to be sent to the somatosensory cortex.
7
Q
How are prostoglandins activated?
A
Immune cells convert their phospholipids into arachidonic acid when damaged, this is then converted int prostoglandin F2 by the COX 1 and COX2 enzymes.
8
Q
What is the role of COX1 in platelets?
A
Arachidonic acid is converted into thromboxane A2 by COX1. This leads to platelet aggregation.
9
Q
Why are NSAIDs contraindicated in kidney disease?
A
COX in the kidney maintains reneal blood flow, so use of NSAIDS can lead to nephritis.
10
Q
What issues do NSAIDS cause in the stomach?
A
Decrease acid production and can lead to nausea, vomiting, dyspepsia and ulceration
11
Q
Why are NSAIDs contraindicated in asthma?
A
May exacerbate asthma symptoms and cause bronchiospasm
12
Q
What is the definition of an antibiotic?
A
Substance produced by microorganisms that inhibits the growth of or kills other bacteria
13
Q
What is susceptibility?
A
The level of vulnerability of a microorganism to an antimicrobial.
14
Q
Which antimicrobials inhibit cell wall synthesis?
A
Beta lactams and glycopeptides
15
Q
What are the different types of beta lactams?
A
Penicillin’s, cephalosporins, monobactams and carbapenems
16
Q
What is the mechanism of action of a beta lactam?
A
Interfere with the assembly of the cell wall by inhibiting transpeptidase enzymes
weakens cell wall
Lysis of microorganism
17
Q
What type of bacteria do glycopeptides target?
A
Gram positive
18
Q
Examples of glycopeptides?
A
Vancomycin
19
Q
How do aminoglycosides work?
A
(has amino in the name)
Inhibits protein synthesis via 30s ribosome inhibition
20
Q
Which antibiotic shouldn’t be used in pregnancy?
A
Trimethoprim, as it inhibits folic acid synthesis.
21
Q
What is nitrofurantoin used to treat?
A
Uncomplicated UTI’s
22
Q
How does a tetracycline work?
A
Inhibition of protein synthesis.
23
Q
What is metformin used to treat?
A
Diabetes mellitus
24
Q
How is metformin excreted?
A
Via active tubular excretion in the kidneys
25
What is active tubular excretion?
The transfer of materials from the peritubular capillaries to the renal tubular lumen to be excreted.
26
What is meant by the half life of a drug?
The time required for the serum concentration of the drug to decrease by 50%
27
What precautions should be taken with metformin and IV contrast?
There is a risk of lactic acidosis if patients on metformin are given IV contrast.
28
How long should metformin be with held for before IV contrast is given?
48 hours
29
How can a prescription be altered to reduce the effects on renal function?
Reduce dose, lengthen interval or substitute the drug.
30
How does metformin work?
Suppression of gluconeogenesis in the liver,
31
Is there weight gain associated with metformin?
No, it in fact often decreases appetite and causes weight loss.
32
What type of drug is ramipril?
ACE inhibitor
33
How do ACE inhibitors work?
Inhibits the conversion of angiotensin 1 into angiotensin 2
34
What does angiotensin 2 bind to which is inhibited with ACE inhibitors?
Binds to smooth muscle.
When this is inhibited there is a decrease in intracellular calcium.
This causes vasodilation.
35
Which other hormone does angiotensin 2 promote the release of?
Aldosterone
36
Should you be concerned about renal function when starting ramipril?
Renal function should be checked before starting and before increasing the dose of ramipril.
37
What is the most common side effect of ACE inhibitors?
Chronic cough occurring in 10-30% of patients
38
Why are ACE inhibitors less commonly used in afro-Carribean patients?
They commonly have low renin essential hypertension.
| this means their RAAS system is contributing very little to their hypertension.
39
What group of drugs does atorvastatin belong to?
Statins
40
What do statins do?
Lower the levels of cholesterol in the blood
41
Which enzyme do statins inhibit?
HMG-CoA reductase
42
What is the function of HMG-CoA reductase?
The conversion of HMG-CoA to mevalonate is an early rate-limiting step in cholesterol biosynthesis.
By inhibiting it there is less cholesterol.
43
What is St Johns wart?
A herbal medicine used to treat the symptoms of mild and moderate depression.
44
What does St Johns wart interact with?
SSRI's, oral contraceptive pill, warfarin, cyclosporin, HIV medication, Digoxin, statins etc.
45
What class of drug would be used in a patient with a new diagnosis of depression?
An SSRI
46
How does an SSRI work?
Blocks the serotonin reuptake transporter so the serotonin remains in the synapse longer and had longer to take effect.
47
What class of drug is amitriptyline?
A TCA
48
How does a TCA work?
It blocks a combination of serotonin, nor adrenaline, muscarinic and histamine receptors
Its good for treating neuropathic pain
49
What would you advise a patient with severe diarrhoea about their combined oral contraceptive pill?
To take a break from their pill when they have severe diarrhoea and use other precautionary measures.
The diarrhoea stops the pill from being absorbed and increased the risk of getting pregnant.
50
What is Loperamide?
Anti diarrhoea
51
How does loperamide work?
Opioid receptor agonist
reduces GI tract motility
Increases the time the material stays in the intestine allowing more water to be absorbed into the faecal matter.
52
What is methotrexate?
A DMARD used to treat RA
53
What is a DMARD?
A drug which treats the underlying cause rather than just the symptoms.
It acts to reduce swelling, pain and stiffness over the course of a few weeks.
54
How does methotrexate work?
It prevents nucleic acid synthesis and causes cell death.
55
Why is folic acid given to someone on methotrexate?
Its given once a week on a different day to the methotrexate.
It acts to counteract the folate antagonist action of methotrexate.
56
How should the patients on methotrexate be managed?
Patients should have a FBC, renal and liver function tests before starting treatment and every 1-2weeks until therapy is stabilised.
57
What types of drug are Doxazosin and tamsulosin?
Alpha 1 blockers
58
How does Tamsulosin work?
Relaxes the muscles in the bladder and prostate to allow you to urinate more easily.
59
Why is it important for a doctor to know if a patient is taking tamsulosin if they need cataract surgery?
Intraoperative floppy iris syndrome has been observed in patients taking tamsulosin when having cataract surgery.
60
A patient on Tamsulosin complains of dizziness after standing up after taking their medication. What would you suggest?
Postural hypotension is a side effect of tamsulosin
Check BP
Take it at night to try and reduce the side effects.
61
Why can tamsulosin cause retrograde ejaculation?
The seminal fluid can flow into the bladder due to the failure of the bladder neck to close.
62
What is Tegretol (carbamazepine)?
Used to prevent ad control seizures,
| An anticonvulsant or anti-epileptic drug.
63
Why should contraception be reviewed if the patient is started on carbamazepine?
The efficacy of the combined oral contraceptive pill is reduced by hepatic interactions with carbamazepine
They should be advised to take the progesterone only pill or IUD's
64
What monitoring should be done when a patient starts on carbamazepine?
FBC, U&E, LFTS
65
What should a patient do if they find out they are pregnant whilst taking carbamazepine?
They should keep taking the medication as the risk of foetal defects is much less than the potential harm caused by not taking the Carbamazepine
66
What is Adcal?
A tablet containing calcium and vitamin D prescribed to people to prevent osteoporosis
67
What is alendronic acid?
A bisphosphonate used to prevent osteoporosis
68
What is Letrozole used for?
First line treatment in post menopausal women with hormonal dependent advanced breast cancer.
69
How should a patient be advised to take alendronic acid>
Take tablets with plenty of water whilst sitting or standing.
Take on an empty stomach at least 30mins before breakfast
They should stop taking the medication if they get oesophageal irritation, dysphagia, heartburn or pain on swallowing .
70
How does alendronic acid work?
Inhibits osteoclast mediated bone resorption.
71
What is meant by the term prophylaxis?
A treatment given or an action taken to prevent disease
72
What is Clenil modulite?
A drug used in the prophylaxis of asthma
73
What is salbutamol used for?
It is used to treat acute symptoms during exercise.
74
What is a spacer?
An add on device used to increase the ease of using an inhaler.
75
How would you use a spacer?
The inhaler is sprayed through the spacer then the patient breaths normally 5-10 times through the spacer.,
76
What is pharmacokinetics?
What the body does with the drug e.g. absorption, distribution, metabolism and excretion.
77
Are ionised molecules water or lipid soluble?
Water soluble
78
What is the bioavailability of a drug?
The fraction of the administered drug that reaches the the systemic circulation unaltered.
79
What is a loading dose of a drug?
If it has a long half life it may take a while for it to reach a steady level of drug.
So giving a loading dose, loads the system and shortens the time to steady state.
80
Why is an IV infusion of a drug better in some circumstances?
A steady state is reached within the therapeutic index.
81
Why might injecting drugs once a day not be the best mode of admission?
There will be peaks and troughs in the levels of drug in the blood stream.
This may lead to the drug concentrations being outside of the therapeutic window.
82
Which cranial nerves have parasympathetic componenets?
3,7,9,10
83
What receptors does Ach work on in the spinal cord?
Nicotinic
84
Which receptors do post ganglionic parasympathetic fibres which release Ach act on?
Muscarinic receptors
85
Which receptors do post ganglionic sympathetic fibres which release noradrenaline act on?
Alpha and beta adrenoreceptors
86
If morphine is given orally how much is metabolised in the first pass metabolism?
50%
87
How much less morphine should you give IV compared to orally?
Half the dose
88
How do opioids work?
Cross the blood brain barrier
Binds to opioid receptors on pain signalling neurons
They prevent neurotransmitters from being released in order to manage pain
89
What are the side effects of opioids?
Respiration depression, sedation, n&V, constipation, itching, immune suppression
90
What should you do in patients with reduced renal function?
Reduce dose and timing interval.
Morphine is metabolised to to a more potent substance. In normal renal function this is excreted quickly but in renal failure it can lead to respiratory depression.
91
What is synergy?
Interaction of drugs that the total effect is greater than the sum of the individual effects
92
What is antagonism?
A substance that acts against and blocks the action.
93
What is summation?
Different drugs used together have the same effect as a single drug would.
94
What is potentiation?
Enhancement of one drug by another so that the combined effect is greater than the sum of each one alone.
95
What is pharmacodynamics?
The effect the drug has on the human body
96
What is a narrow therapeutic index>
Where small differences in dose or blood concentration may lead to serious therapeutic failure or adverse drug reactions
97
Variables of the absorption of a drug?
pH
Vascularity (shock reduces absorption)
Surface area
contact time (with food, slower gastric emptying)
98
What is the first pass hepatic metabolism
Only a proportion of the drug reaches the circulation due to the liver metabolising it.
99
What is the distribution of a drug?
Refers to the movement of a drug to and from the blood and various tissues of the body.
100
What is cytochrome P450?
Enzymes essential for the metabolism of many drugs
101
What is an agonist?
A compound that binds to a receptor and activates it
102
What is the potency of a drug?
The concentration of which is required for the drug to be effective
103
What is the efficacy of the drug?
The maximum response achievable
104
What is medicines adherence?
The importance of a patients belief and the health professionals knowledge in order to achieve a more patient centred approach
105
What is the mechanism of ticagrelor?
Inhibits the binding of ADP to platelets
