DRUGS Flashcards
1
Q
A
2
Q
what medicines are typically used to induce mydriasis?
A
tropicamide
phenylephrine
3
Q
what is the mechanism of action of tropicamide?
A
- muscarinic (M3) antagonist
- stops ACh binding to M3 receptors
- stops circular muscle contraction
- stops pupil constriction
4
Q
what is the mechanism of action of phenylephrine?
A
- alpha-adrenoceptor agonist
- binds to receptors and causes radial muscles of iris to contract
- increases pupil size
5
Q
what % of tropicamide is standard?
A
0.5%
6
Q
what % of phenylephrine is standard?
A
2.5%
7
Q
what % is the standard does of pilocarpine?
A
2%
8
Q
what medicines can be used to induce myopia?
A
pilocarpine
9
Q
list 3 tricyclic ADs
A
desipramine
amitriptyline
clomipramine
10
Q
desipramine, amitryptyline, clomipramine are all what type of antidepressant?
A
tricyclic
11
Q
list 3 SSRIs
A
fluoxetine
paroxetine
flucoxamine
sertraline
citalopram
12
Q
fluoxetine, paroxetine, flucoxamine, sertraline, citalopram - what type of antidepressant are these?
A
SSRIs
13
Q
list 2 SNRIs
A
venlafaxine
duloxetine
14
Q
venlafaxine and duloxetine are examples of what type of antidepressant?
A
SNRIs
15
Q
what does each antidepressant block?
A
tricyclics and SNRIs - SERT and NAT
SSRIs block only SERT
16
Q
what is the mechanism of action of propofol?
A
GABA agonist - increases inhibitory effect
17
Q
what is the volume of distribution of propofol?
A
- 60L/kg
18
Q
what is the MOA of isoflurane?
A
- reduces gap junction channel opening times
- alters tissue excitability
- induces muscle relaxation
19
Q
what is the MOA of fentanyl?
A
- agonist of mu opioid receptor
- inhibits adenylate cyclase
- = downregulation
- hyperpolarises cell and inhibits nerve activity
20
Q
what is a typical dose of fentanyl?
A
0.05mg/mL IV
21
Q
what is the MOA of suxamethonium?
A
- depolarising neuromuscular blocker
- mimics ACh but not rapidly hydrolysed
22
Q
wh
what is the MOA of atracurium?
A
- non-depolarising neuromuscular blocker
- antagonist of ACh sp. at nicotinic receptors
23
Q
what is the MOA of neostigmine?
A
- inhibits AChE
- prolongs action of ACh
- increases muscular contraction and reverses muscle relaxants
24
Q
what is hte MOA of atropine/glycopyrrate
A
- antagonise muscarinic receptors
- inhibit cholinergic transmission
- decreases bradycardia risk from neostigmine
25
what is the MOA of mannitol?
* increases blood plasma osmolarity
* increases flow of water from tissues
* decreases ICP
26
what is the MOA of depakote?
* folate antagonist
* blocks reuptake of GABA into glia cells
27
what is the MOA of paracetamol?
* selective COX2 inhibitor
* Inhibits production of prostaglandins (anti-inflammatory) and thromboxanes (anti-platelet)
28
what is the typical dosage of paracetamol
0.5-1g every 4-6 hours to max of 4g daily
29
what is the MOA of ibuprofen?
Weak COX 1 inhibitor
30
what is the typical dosage of ibuprofen
300-400g 3-4 times daily to max of 2.4g
31
what is the MOA of co-codamol
* opiod prodrug
* Mainly binds to Mu receptors
* Inhibits adenylyl cyclase
* Reduces intracellular cAMP
* Opens K channels
* Causes hyperolarisation
* Inhibits Ca2 opening
* Reduces NT release
32
what is the MOA of morphine?
* opioid prodrug
* Mainly binds to Mu receptors
* Inhibits adenylyl cyclase
* Reduces intracellular cAMP
* Opens K channels
* Causes hyperolarisation
* Inhibits Ca2 opening
* Reduces NT release
33
what is the MOA of gabapentin?
* anticonvulsant
* Increases GABA concentration by modifying Ca channels
34
what is gabapentin used to treat
neuropathic pain
35
what is the typical dosage of gabapentin
300mg OD on day 1
300mg BD on day 2
300mg x3 on day 3
36
what is the MOA of lidocaine?
* local anaesthetic
* Blocks Na channels
* Prevents generation of AP in pain fibres
37
what is the MOA of tricyclics
* Blocks reuptake of NAdr and 5HT
* Increases conc in synaptic clefts
38
what are the MOA of thrombolytics, like TPA
Inactivates thrombin and ADP
Cleaves plasminogen to form plasmin
Plasmin cleaves fibrin to degrade thrombi
39
what is the MOA of warfarin
Vit K antagonist
Vit K is a cofactor in the formation of coagulation factors VII, IX, X and thrombin
40
what is the MOA of aspirin
Inhibits the function of platelets in clot formation
41
what is the MOA of statins
Inhibit HMG-CoA reductase, the rate limiting enzyme in cholesterol synthesis
42
what is the MOA of SSRIs like sertraline
Selectively block serotonin reuptake transporter proteins
Increases concentration of 5HT in synapse
43
what is the MOA of pregabalin
* anticonvulsant that increases GABA synaptic conc
44
what is the MOA of benzodiazapine
* anticonvulsant
* Binds to alpha subunit of GABA-A receptor = ion channels open
* Causes influx of Cl- ions = hyperpolarisation
* Reduces anxiety
45
what is the MOA of SNRIs like venlafaxine
Blocks 5HT and Nadr reuptake transporter proteins
Increases conc in synaptic cleft
46
what is the MOA of MAOIs
Prevents reuptake of Nadr 5HT and DA
47
what is the MOA of L-dopa
Precursor or DA
Decarboxylated into DA after crossing BBB
Stimulates dopaminergic receptors
48
what is the MOA of benserazide
Peripherally-acting DOPA decarboxylase inhibitor
Reduces peripheral side effects of L-Dopa
Doesn’t cross BBB so doesn't prevent the effects of L-dopa in brain
49
what is the MOA of carbidopa
dopa decarboxylase inhibitor used in combination with levodopa
50
51
what is the MOA of selegiline
Irreversible MAOB inhibitor
Increases DA in pre-synaptic neurone after reuptake
Allows more DA to be repackaged into vesicles via VMAT
52
what is the MOA of rasagiline
Irreversible inhibitor of MAO
53
what is the dosage of rasagiline
1mg daily
54
what is the MOA of entacapone
selective COMT inhibitor used in treatment of PD
55
what is the MOA of entacapone
200mg given with each dose of L-dopa
56
what is the MOA of risperidone
antipsychotic
Blocks D2 receptors in ventral striatum, alleviating =+ve symptoms of SZ
Blocks 5HT2 receptors in mesocortical tract - causing excess of DA
57
what is hte MOA of olanzipine
D1, D2, D4, 5HT and muscarinic receptor antagonist
| 2nd generation antipsychotic
58
what is the MOA of quetiapine
D1, D2, 5HT antagonist
59
what is the typical dosing of olanzipine
10mg daily and adjusted accord to response
60
what is the typical dosage of quetiapine
25mg BD for day 1
50mg BD for day 2
100mg BD for day 3
150mg BD for day 4
61
what is the MOA of aripiprazole
D2 partial agonist with weak 5HT agonism
62
what is the typical dosage of aripiprazole
10-15mg OD
63
what is the MOA of amisulpride
Selectivee dopamine receptor antagonist with high affinity for mesolimbic D2 and D3 receptors
64
what is the MOA of clozapine
D1, D2, 5HT muscarinic receptor antagonist
65
what is hte MOA of propofol
Strong agonist at mu opioid receptor
Inhibits adenylate cyclase
Inhibits release of nociceptive substances
66
what is the MOA of suxamethonium
Mimics ACh but isn't broken down by AChE
Desensitises the NMJ
Depolarising
67
what is the MOA of atracurium
Blocks ACh receptors in NMJ
68
what is the difference between suxamethonium and atracurium
suxamethonium = depolarising
atracurium = non-depolarising
69
what is the MOA of isoflurane
MOA unknown
Inhaled volatile anaesthetic agent - maintains anaesthesia
70
what is the MOA of fentanyl
Strong agonist at mu opioid receptor
Inhibits adenylate cyclase
Inhibits release of nociceptive substances
71
what is the MOA of neostigmine
Blocks AChE
Increases conc. Of Ach in NMJ
Increases muscle contraction
72
what is the MOA of glycopyrolate
Muscle receptor antagonist
Limits parasympathetic effects caused by neostigmine eg. bradycardia
73
what is the difference between glycopyrolate and atropine?
atropine can cross the BBB wheres glycopyrolate cannot
74
what is the MOA of mannitol
osmotic diuretic
Increases solute content in proximal tubule of kidneys
Decreases fluid in body and increases plasma osmolarity
Reduces ICP
75
