Drugs Flashcards

(45 cards)

1
Q

Triptans (Sumatriptan etc)

A

Used to treat migraines

They are selective 5HT1B/5HT1D agonists

5HT1B receptors are on smooth muscle and voasconstriction

5HT1D lies on trigeminal nerve terminals and blocks release of vasoactive peptides from trigeminal nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What drugs are used in the prophylaxis of migraine?

A

B-blockers (bisoprolol, propanolol etc)

Antiepileptic drugs (gabapentin, pregabalin etc)

Antidepressants (Amitriptyline etc)

Calcium channel blockers (Nifidipine etc)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Tissue plasminogen activator (tPA)

A

Used to treat ischaemic stroke only

Disperses thrombus and restores blood flow

Must be administered in 3 hours for maximum effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Stroke prophylaxis

A

Antihypertensives

Statins (reduces risk of thrombus formation but also contraindicated in haemorrhagic stroke)

Antiplatelets (Aspirin, clopidogrel)

Anticoahulants (Warfarin)

Compression stockings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Orlistat

A

Only centrally acting licensed drug in the UK for obesity

Acts as a lipase inhibitor and prevents the breakdown of dietary fats to fatty acids as well as decreasing the absorption of fats by 30%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Side effects of orlistat

A

Oily stools, abdominal cramps, flatus with discharge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Anti epileptics (VGSC blockers)

A

Phenytoin, Carbamazepine, Lamotrigine, Sodium Valproate

Keeps the VGSC in an inactivated state allowing it to produce 1 AP but not many successive AP’s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Anti-epileptics (VGCC blockers)

A

Ethosuxamide, Gabapentin, phenytoin

Allows for AP causes by VGSC but does not allow it to be propagated by VGCC’s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Levetiracetam

A

Anti epileptic that directly reduces vesicle fusion hence there is less Glu release therefore less neuronal excitation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Vigabatrin

A

Anti-epileptic that increase GABA synthesis causing more inhibition of neurones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Tigabine

A

Anti-epileptic that reduces the reuptake of GABA allowing for inhibition of neurones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How do benzodiazepines and barbituates help with epilepsy?

A

They increase the effectiveness of GABAa receptors which are Cl- channels which will prolong channel open time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Felbamate

A

Anti-epileptic that blocks NMDAr’s thereby reducing AP’s

However very hepatotoxic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Topiramate

A

Anti-epileptic that blocks AMPA/Kainate receptors thereby reducing AP’s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Retigabine

A

Anti-epileptic that activates K+ channels and makes the neurone less excitable both pre/post synaptically

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Lesigamane

A

Anti-epileptic that blocks low threshold Na currents which decreases the propagation of AP’s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

L-DOPA

A

Aimed at replacing the lost DA in Parkinson’s

L-DOPA is converted to DA by DOPA decarboxylase thereby causing increased DA synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Carbidopa/bensarzide

A

Co-administered with L-DOPA to as a peripheral DA blocker to reduce the peripheral side effects of L-DOPA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Selegiline

A

MAO inhibitor to reduce degradation of DA

20
Q

Baclofen

A

Used for antispasticity

Targets and reduces motor output in the spinal cord

21
Q

Z-drugs (Zopiclone, zolpidem, zolepton)

A

Non-benzo’s which bind to GABAa receptors

Has a short duration of action

Less likely than benzo’s to cause rebound insomnia

Can cause dependence

22
Q

Typical antipyschotics (1st gen)

A

Eg Chlorpromazine, Haloperidol

High affinity D2 antagonists

Effective against the +ve symptoms of Schizophrenia via D2 blockade in the mesolimbic pathway

Around 80% block required for antipsychotic effects to occur

23
Q

Extrapyramidal side effects of 1st gen antipsychotics

A

Acute dystonias (Parkinson like)

Tardive dystonias (Huntingtons like)

Galctorrhea caused by increased prolactin release due to D2 block in TI pathway

Decreased pleasure due to inhibition of mesolimbic pathway

24
Q

Non dopamine related side effects of typical antipsychotics

A

Antipsychotics are also antagonists at other GPCR’s

Can cause sedation (H1)

Hypotension (alpha adrenergic receptors)

Blurred vision, dry mouth, constipation (Muscarinic)

Sexual dysfunction (muscariinic, adrenergic and dopaminergic)

25
Atypical antipsychotics (2nd gen)
Eg Clozapine, Olanzipine, Rispiredone, aripiprazole Low affinity D2 block so causes partial block of D2 but also of 5HT2 recepetors 5HT2 blockade reduces inhibition of DA neurons in mesocortical pathway and nigrostriatal pathway as they don't appear elsewhere This reduces treats the -ve symptoms and also reduces the motor side effects seen with typical antipsychotics
26
Side effects associated with atypical antipsychotics
Weight gain and diabetes Agranulo cytosis/leukopenia (rare and occurs moreoften with clozapine)
27
Why is clozapine different to other atypicals?
The only antipsychotic shown to be clinically more effective than the others However has serious side effects of agranulo cytosis/leucopenia and other blood dyscrasis Only given if more than 2 other antipsychotics have been tried and were ineffective
28
Cholinesterase inhibitors
Eg Donepazil, rivastigmine, galantamine Used in treatment for alzheimers (Does not slow progression) ACH is important in memory formation so these act to reduce ACh breakdown in synapses thereby enhancing levels of ACh
29
Memantine
Non-competive NMDA receptor blocker Is neuroprotective in some way or form and can cause slight cognitive improvement
30
Irreversible MOAi
Eg Phenezine, Tranyleypromine, iproniazid Used in treatment of depression Irreversibly inhibits MAO which inactivates DA/NA/5HT Problematic as consumption of cheese can result in gut MAO not metabolising tyramine due to block resulting in sympathomimetic side effects
31
Moclobemide
Used in depression treatment Safer to use than irreversible inhibitors as high concentrations of tyramine can overcome the block in the gut Therefore there is much less chance of the cheese reaction occurring
32
Long acting hypnotics
Flurazepam/Dalmane/Diazepam (2-keto metabolised in liver) Long duration of action owed to active metabolites Can result in a 'hangover' effect due to long duration of action
33
Short acting hypnotics
Restoril/Tempazepam/Triazolam/Halcion (3-OH converted to glucaronide radicals) Shorter half life and duration of action than 2- keto benzo's Little to no hangover effect Rophynol is part of this class and is known as the date rape drug
34
Herbal hypnotics
Valerian root The active ingredients are suggested to bind to 5HT, GABA and adenosine receptors
35
Benzodiazepines
Diazepam, Binds to allosteric sites on GABAa receptors (CL- channels) increasing their activity Binds between alpha/gamma subunits
36
TCA's
Tricyclic antidepressants eg imipramine, amitriptyline Blocks the uptake of monoamines with preference for 5HT/NA over DA Competitive and non selective Blockade of histamine and ACh recpetors contributes to side effects Major metabolites are also active
37
Major side effects of MAOi's
Hypotension Atropine like effects Hepatocellular jaundice
38
Major side effects of TCA's
``` Sedation Atropine like effects Postural hypotension Mania and convulsions Dysrhythmia and heart block ```
39
SSRI's
Citalopram, Fluoxetine, Sertraline Much more selective for 5HT receptors and so have less S/E from NA enhancement Much safer in overdose as well
40
Mirtazipine
Blocks alpha2 adrenceptors/5HT2C receptors causing enhanced NA/5HT release
41
Trazodone
Blocks 5HT2A/2C and 5HT reuptake
42
Mianserin
Blocks multiple 5HT receptors as well as alpha 1/2 adrenoceptors
43
Agomelatine
Blocks melatonin receptors Useful in depression that causes sleep disturbance
44
Lithium
Reduces both mania and depressive phases Possibly permeates through Na+ but doesn't leave causing depolarisation of excitabel cells Also inhibits IP3 >1.5mmol is toxic
45
Lithium side effects
``` Polyuria/Polydipsia (too much drinking/urinating) Weight gain Aggravation of skin disorders Tremors and muscle twitching GI symptoms Drowsiness Hyper-reflexia, Coma Huntington/Parkison like symptoms ```