Drugs Flashcards
1
Q
What do you give for secondary prevention of MI?
A
Aspirin Clopidogrel Beta blocker ACEi Statin
2
Q
4 anticipatory medications given by syringe driver at end of life
A
Pain- diamorphine
Agitation- midazolam
N+V- haloperidol
Secretions- hyoscine butylbromide
3
Q
Side effect of omeprazole?
A
Hypomagnesaemia–> tetany and ventricular arrythmia
4
Q
What is loperamide?
A
Anti-diarrhoeal
5
Q
What is the generic name for loperamide?
A
Codeine phosphate
6
Q
Does loperamide have analgesic effects?
A
No
7
Q
How do opioids prevent diarrhoea/cause constipation?
A
Agonists of opioid u-receptors in GI tract, increases non-propulsive contractions and decreases propulsive (peristaltic) contractions. Transit is slowed and anal sphincter tone is increased. More time for water absorption so stool hardens.
8
Q
Contraindications of loperamide?
A
Acute UC, C.diff and dysentry- as risk of megacolon and perforation.
9
Q
Other name for senna?
A
Docusate
10
Q
How does senna work?
A
Stimulant. Increase water and electrolyte secretion from colonic mucosa so colonic volume is increased and peristalsis increases. Also direct pro-peristaltic action
11
Q
Contraindications of senna
A
Bowel obstruction
Avoid rectal route in haemorrhoids/anal fissure
12
Q
What drug class is mesalazine/sulfasalazine?
A
Aminosalicylate
13
Q
What is the indication for mesalazine?
A
Ulcerative colitis
14
Q
What is the indication for sulfasalazine?
A
Rheumatoid arthritis
15
Q
How does mesalazine work?
A
Topically on the gut. Releases 5-aminosalicylic acid- anti-inflammatory and immunosuppresant.
16
Q
Why isn’t sulfasalazine used in UC?
A
broken down to sulfapyridine which treats RA but has side effects in UC.
17
Q
Side effects of aminosalicylates
A
Leucopenia, thrombocytopenia, renal impairment, oligospermia
18
Q
What is the route of mesalazine?
A
Rectal
19
Q
What does metoclopramide do?
A
Anti-emitic
20
Q
What class of drug are metoclopramide and domperidone?
A
Dopamine D2-receptor antagonists
21
Q
How does metoclopramide/domperidone work?
A
D2 is the main receptor in the chemoreceptor trigger zone (area responsible for sensing emetogenic substances in the blood.) Dopamine is the neurotransmitter.
Also a neurotransmitter in the gut so increased gut motility (decreased gut motility may cause nausea)
22
Q
Contraindications of metoclopramide/domperidone?
A
GI obstruction
Perforation
23
Q
Side effect of metoclopramide/domperidone?
A
Extrapyramidal syndromes- acute dystonic reaction e.g. oculogyric crisis
24
Q
Possible interactions of metoclopramide/domperidone?
A
Antipsychotics (increased risk of side effects)
Dopaminergic agents used in parkinsons (antagonises these)
25
What type of diuretic is furosemide?
Loop
26
How does furosemide work?
Inhibits Na/K/Cl co-transporters in the ascending loop of Henle so water doesn't follow these ions into the cell. i.e. prevents water reabsorption.
Also vasodilation so reduces preload of heart and increased contractility of overstretched heart muscle.
27
Indications for furosemide?
Pulmonary oedema
| Fluid overload e.g. CHF, liver failure, renal disease
28
Contraindications of furosemide
Hypovolaemia
| Dehydration
29
Unexpected side effect of furosemide?
Hearing loss and tinnitus
30
Possible interactions of furosemide?
May effect drugs excreted by the kidneys e.g. increased risk of digoxin toxicity, of oto+nephrotoxicity of aminoglycosides
31
Name 2 thiazide like diuretics
Bendroflumethiazide
| Indapamide
32
Where do thiazide like diuretics act
DCT
33
Contraindication of thiazide like diuretic
Hypokalaemia
34
Unexpected side effect of thiazide like diuretic
Impotence
35
Efficacy of thiazide like diuretics is reduced by what?
NSAIDs
36
Name 3 potassium sparing diuretucs
Amiloride
Co-amilofruse
Spironolactone
37
Where do potassium sparing diuretics act?
DCT
38
Indication for potassium sparing diuretic
Hypokalaemia from loop or thiazide diuretics- is used in combination as quite a weak diuretic alone.
39
Contraindications of potassium sparing diuretic
Renal impairment
Hyperkalaemia
Don't start in hypokalaemia is unpredictable effects on K+
40
Name 2 alpha blockers
Doxazosin
| Tamulosin
41
How do alpha blockers work
Block alpha 1 adrenoreceptors in smooth muscle (blood vessels, urinary tract) and cause vasodilation (lowers BP) and reduced resistance to bladder outflow
42
Indications for alpha blockers
BPH
| Resistant HTN
43
Contraindications for alpha blockers
Postural hypotension
44
What should you do in terms of interactions on the first day of alpha blocker administration?
Stop beta blockers as block reflex tachycardia in response to vasodilation which could = syncope
45
When should alpha blockers be taken?
Bed time
46
Name a xanthine oxidase inhibitor
Allopurinol
47
How does allopurinol work?
Prevents the conversion of purine to xanthine (via inhibition of the enzyme xanthine oxidase), xanthine would normally go on to become uric acid. So plasma uric acid conc is lowered.
48
Indications for allopurinol
Prevents:
- gout
- uric acid/calcium oxalate renal stones
- hyperuricaemia
- tumour lysis syndrome
49
Contraindication of allopurinol
Acute gout attack (but continue if already take it)
50
Side effects of allopurinol
```
Skin rash (can=SJS/TEN)
Trigger or worsen gout when start
```
51
Interactions of allopurinol
Inhibit mercaptopurine and azathioprine as they require xanthine oxidase for metabolism
Increased risk of rash to amoxicillin
Increased risk of hypersensitivity reactions to ACEi and thiazides.
52
Name 2 tricyclic antidepressants
Amitryptiline
| Lofepramine
53
How do tricyclic antidepressants work?
Inhibit the reuptake of serotonin and noradrenaline
| also block many receptors: muscarinic, histamine, alpha adrenergic and dopamine which lead to adverse effects!
54
Indications for tricyclic antidepressants
2nd line for depression
| Neuropathic pain off licence
55
Side effects of tricyclic antidepressants
```
Dry mouth
Constipation
Urinary retention
Blurred vision
Sedation
Hypotension
Arrythmias/ECG changes
Convulsions
Hallucinations
Mania
Breast changes
Sexual dysfunction
Tremor/dyskinesia
```
56
Interactions of tricyclic antidepressants
Monoamine oxidase inhibitors (have same action so lead to HTN, hyperthermia, serotonin syndrome)
57
How long should antidepressants be taken for after remission?
6 months after start to feel better
58
Which platelet receptors does clopidogrel bind to? What does this do?
ADP receptors, prevents aggregation
59
Aspirin and clopidogrel act on the same/different pathway
Different
60
Indications for clopidogrel
ACS
Prevent stent occlusion
Long term secondary prevention of thrombotic arterial events
AF where warfarin or NOVACs c/i
61
Contraindications of clopidogrel
Bleeding
| Stop 7 days before elective surgery
62
Side effects of clopidogrel
Bleeding
GI upset
Thrombocytopenia
63
Aspirin mechanism of action
COX inhibition (stops arachidonic acid turning into throboxane which is pro-aggregatory)
64
Is aspirin COX inhibition reversible?
No, lasts for lifetime of platelet
65
Indications of aspirin
```
ACS
Ischaemic stroke
Long term prevention of thrombotic events
AF where warfarin/novac c/i
Pain and fecer
```
66
Aspirin c/is
<16yo Reye's syndrome risk
| 3rd trimester of pregnancy (ductus arteriosus)
67
Is propanolol a particularly selective or non selective beta blocker?
Non selective for B1
68
Which beta blocker has a particularly short half life?
Metoprolol
69
How do beta blockers work?
Act on B1 receptors in the heart, reduce force and speed of contraction. Less cardiac work and oxygen demand, increased myocardial perfusion.
Prolong the refractory period of the AV node
Reduce renin secretion from kidneys (mediated by b1 receptors)
70
Indications for beta blockers
```
Ischaemic heart disease
CHF
AF
SVT
HTN
```
71
Contraindications for beta blockers
Asthma
Heart block
Haemodynamic instability
72
Side effects of beta blockers
```
Fatigue
Cold extremities
Headache
GI upset
Sleep disturbance and nightmares
Impotence
```
73
Interactions of beta blockers
Non dihydropyridine calcium channel blockers e.g. verapamil, dilitiazem as the combination can cause HF, bradycardia and even asystole
74
What are the two types of calcium channel blocker and what are they each selective for?
Non-dihydropyridines (heart)
Dihydropyridines (vasculature)
Dilitiazem is MIXED
75
Name 3 calcium channel blockers
Dilitiazem
Amlodipine
Verapamil
76
How do calcium channel blockers work
Decrease entry of calcium into vascular and cardiac cells so intracellular calcium conc is decreased. This = relaxation and vasodilation of arterial smooth muscle and decreases arterial pressure.
In heart reduces contractility and suppresses cardiac electrical conduction (esp AVN) so ventricular rate decreased so reduced O2 demand of heart.
77
Indications for Ca Ch bs
HTN
Stable angina
SVT
78
Contraindications of non-dihyd ca ch bs
AV node conduction delay
| Caution if poor LV function
79
C/is of dihyd ca ch bs
unstable angina
| severe aortic stenosis
80
Side effects of ca ch bs
Dihydro- Ankle swelling, flushing, headache, palpitations
| Verapamil- constipation, bradycardia, heart block, CF
81
Possible interactions of calcium channel bl
Non dihydro with beta blockers. As both negatively inotropic and chronotropic
82
Name an ACEi
Ramipril
83
What does angiotensin II do?
Vasoconstriction and stimulates aldosterone
84
Contraindications of ACEi
Renal artery stenosis
AKI and caution in CKD
Pregnant
85
Side effects ACEi
Hypotension
Dry cough (increased bradykinin)
Hyperkalaemia
86
What type of drug is losartan
Angiotensin II type 1 receptor antagonist
87
How does losartan work
- Competes with angiotensin II to bind to the type 1 receptor.
- Decreased PVR
- Decreased aldosterone secretion means increased sodium and water excretion which reduces venous return
- Dilates efferent glom. arteriole so decreased intraglom pressure and slows progress of CKD
88
Indication for losartan
Generally when ACE not tolerated due to cough
- HTN
- CHF
- Ischaemic HD
- Diabetic nephropathy and CKD with proteinuria
89
Contraindications for losartan
Same as ACEi.
| Renal artery stenosis, AKI and caution in CKD, pregnant
90
Possible interactions of losartan and ACEi
Other potassium elevating drugs
91
L dopa is always given with ?
Peripheral decarboxylase inhibitor
92
Name an L dopa (and PDI)
Sinemet, madopar
93
Side effects of L dopa
```
nausea
drowsiness
confusion
hallucinations
hypotension
Wearing off effect and on-off effect
```
94
Possible interactions of L dopa/PDI
Antipschotics
| Metoclopramide
95
What is phenytoin?
Anti-convulsant
96
How does phenytoin work?
Binds to inactive neuronal Na channels, prolonging the period of inactivity, so neuronal excitability decreased
97
Indication of phenytoin
- Stop status epilepticus of benzos not working
| - Decrease frequency of epileptic seizures
98
What could phenytoin cause if taken in pregnancy?
Foetal hydantoin syndrome
99
Side effects of phenytoin
```
Skin coarsening
Acne
Hirsutism
Gum hypertrophy
Cerebellar toxicity
Haem disorders
Osteomalacia
```
100
Which drugs decrease the efficacy of phenytoin (not to do with P450)
Drugs that lower the seizure threshold e.g. SSRIs, tricyclics, antipsychotics, tramadol
101
What must patients taking phenytoin be cautious with?
Contraception
102
Which anticonvulsant can be used for trigeminal neuralgia
Carbamezapine
103
Which anticonvulsant is the worst teratogen
Sodium valproate
104
Which anticonvulsant interacts with oestrogen containing contraceptives
Lamotrigine
105
Which anticonvulsant can have psychiatric side effects including suicidal thoughts
Levetiracetam
106
How do cardiac nitrates work?
Decrease intracellular calcium so relaxation of smooth muscle
107
Interaction of nitrates
Slidenafil
108
Contraindications of nitrates
Severe aortic stenosis
Haemodynamic instability
Hypotension
109
Side effect of digoxin given its narrow therapeutic index
Digoxin toxicity
110
Digoxin contraindications
Heart block (2nd and 3rd degree) and ventricular arrhythmias
111
Digoxin interactions
Risk of digoxin toxicity increased by- diuretics, amiodarone, calcium channel blockers and quinine
112
Amiodarone indication
Treatment of tachyarrhythmias (life support)
113
Amiodarone contraindications
Hypotension, heart block, thyroid disease
114
How do heparins work
Inhibit thrombin and factor Xa
115
What type of anticoagulant is enoxaparin?
Heparin
116
How do statins work
Inhibit HMGCoA reductase (enzyme involved in making cholesterol)
117
What type of drug is tiotropium?
Antimuscarinic/anticholinergic
118
When are antimuscarinics contraindicated?
Angle closure glaucoma
119
What are acetylcholinesterase inhibitors used for?
Myasthenia gravis
Glaucoma
Alzheimers/dementia/parkinsons
120
What do antimuscarinics do?
Inhibit acetylcholine
121
How do 5-alpha reductase inhibs work?
inhibiting the intracellular enzyme 5α-reductase, which converts testosterone to its more active metabolite dihydrotestosterone. As dihydrotestosterone stimulates prostatic growth, inhibition of its production by 5α-reductase inhibitors reduces prostatic enlargement and improves urinary flow.
122
How long do 5-alpha reductase inhibs take to work?
Months
123
Side effects of 5-ARI
Impotence, reduced libido
Gynaecomastia
Hair growth
Breast cancer
124
Men taking 5-ARI must be careful not to......?
Have unprotected sex with a pregnant woman
125
How does gliclazide work
stimulates pancreatic insulin secretion
126
Side effect of gliclazide
Weight gain
127
Name a biguanide
Metformin
128
How does metformin work
increases the response (sensitivity) to insulin. It suppresses hepatic glucose production (glycogenolysis and gluconeogenesis), increases glucose uptake and utilisation by skeletal muscle and suppresses intestinal glucose absorption
129
Do metformin and gliclazide carry a risk of hypoglycaemia?
Metformin no, gliclazide yes
130
Contraindication of metformin
Severe renal impairment
