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Flashcards in Drugs used in migraine Deck (47):
0

what is a migraine ?

headache accompanied by nausea, vomiting, photophobia and phonophobia
headache: idiopathic, paroxysmal, recurring, moderate to severe attacks, unilateral, throbbing, exacerbated by physical activity

1

what other symptoms are sometimes reported with migraines?

muscle pains
cognitive disruptions
autonomic symptoms - relatively rare

2

what do most people have to do if they are suffering from a migraine ?

most people have to go and lie down until it passes, often in a dark and silent room

3

what can induce the onset of a migraine ?

often the onset is unclear but sometimes stress can induce them

4

how many people are affected by migraines ?

10-15% of worlds adult population
it is the 19th most common debilitating condition according to WHO

5

which gender suffers more from migraines ?

18% females and 6% males

6

when do migraines usually start ?

they begin around puberty and this increases to peak around 40s and the disappears

7

what are the 2 types of migraine?

classical= 20% pain with aura
common= 80% pain without aura

8

what is aura ?

it is a focal neurological symptom
for diagnosis:
2 attacks with aura symptoms
3 of the following - transient, develop over 4+ minutes, aura lasts

9

what is 99% of aura made up of ?

visual disturbances
- zig zag lines
- shimmering lights
- spreading to whole field of vision

10

what are the other disturbances caused by aura ?

SENSORY DISTURBANCES- numbness, spreading numbness that starts at the fingers and spreads to arms and then shoulder
APHASIC- difficulty speaking
BASILAR- loss of balance, double vision and fainting- this is in extreme cases
alternating body sites are affected with different attacks

11

what re the 5 distinct stages of migraines?

prodromal (30-40%)- awareness that you are likely to develop a migraine
aura (20%)- this is only present in classical migraines
headache- moderate to severe
resolution
postdromal- you dont feel 100% still you can sometimes feel nauseous

12

how long can attacks last for ?

last between 4-72 hours

13

what is the average number of attacks per year which migraine sufferers suffer from ?

12

14

what are the percentage of sufferers which have a family member that also suffers from them ?

80%

15

what is a thunderclap migraine?

this is when a headache starts all of a sudden

16

what are the causes of familial hemiplegic migraine ?

P/Q calcium channel chromosome 19- this accounts for about 50% of cases- it affects ion channels or proteins involved in maintaining ionic bases
Na+/K+ pump - chromosome 1

this form is relatively rare

17

what are the 2 main theories for sporadic migraines ?

vascular theory
neurovascular theory

18

what is the vascular theory ?

traditional theory
states that auras are caused by vasoconstriction of cerebral blood vessels followed by vasodilation which causes the headache- thought that this causes the visual and cognitive disturbances


19

why is the vascular theory too simple ?

most patients dont experience aura therefore it doesnt explain what happens in the patients not suffering from aura
doesnt explain the premonitory features- the prodromal phase
recent blood flow studies do not support vascular theory because it appears that constriction is not followed by dilation

20

what is the neurovascular theory ?

dilation of blood vessels and pain is triggered by neural rather than vascular signals

serotonin, nitric oxide, CGRP, substance P are all thought to be involved- serotonin and substance P are involved in pain and inflammation

in some patients cortical spreading depression is involved- ongoing reduction in nervous activity that spreads from 1 region of the brain to the next

21

what are 2 methods of treatment ?

prophylaxis - ongoing treatment to prevent attacks
acute attacks- take treatment when you start to have an attack

22

what are some simple analgesics used as acute treatment of migraines and what are the side effects ?

aspirin, ibuprofen, diclofenac and paracetamol - these are the most common ways to deal with migraines

side effects- GIT discomfort (due to inhibition of prostaglandin production), peptic ulceration and GIT bleeding

23

what compound analgesics/antiemetics are used for acute treatment of migraines ?

- gastric stasis is reduction in gastric contractions which will reduce the ability to absorb drugs - this occurs in migraines
antiemetics are used to reduce nausea to also improve drug absorption

- metaclopramide (D2 antagonist)/aspirin
- metaclopramie/paracetamol
- domperidone/paracetamol
- lysine/aspirin/metaclopramide- the lysine increases aspirin absorption

24

what is ergotamine ?

acute treatment for migraines
- vasoconstrictor of blood vessels
- serotonin and dopamine receptor agonist
- used for 50 years but no longer really used due to its adverse effects

25

what are the adverse effects of ergotamine ?

nausea, vomiting, abdominal pain, muscular cramps
overuse headache- body will adapt to ergotamine so you have to take more and more to overcome the headache
peripheral vasospasm
cold extremities, gangrene - as blood supply to extremities gets cut off
high first pass metabolism

26

what are the contraindications associated with ergotamine?

pregnancy, CHD, peripheral vascular disease

27

what are triptans ?

serotonin 1B/D agonists such as sumatriptan
highly specific for receptors in cranial blood vessels therefore very few peripheral side effects
cause vasoconstriction
activates serotonin receptors in trigeminal nuclei of brainstem- some of the pain associated with migraines appears to be caused by these nuclei
inhibits dural neurogenic inflammation
sumatriptan is effective in 60% of patients

28

what are the side effects associated with triptans?

they are often frequent, and short lived
tingling/heat in head, neck, chest and limbs

other side effects of sumatriptan
- chest related symptoms- 40% of patient, pressure in chest and arms, shortness of breath, mimic angina
- nausea
- dizziness,
- flushing
- fatigue
some of these effects can be avoided by taken it as a nasal spray

29

what are the contraindications associated with sumatriptan ?

angina/mi
uncontrolled hypertension
pregnancy/lactation
children and >65
also drug interactions with SSRIs, MAOIs and lithium

30

what does it mean by triptan wars ?

the triptans were a major breakthrough and therefore many variations of them were produced
- enable less headache recurrence
- faster acting
- it meant that if one was not effective another one could be tried

31

what are examples of other triptans than sumatriptan ?

naratriptan- most common because it has less interactions, fewer side effects
zolmitriptan
rizatriptan
almotriptan
eletriptan
frovatriptan

32

when is prophylactic treatment used for migraines ?

2-4 attacks per month
interfering with patients lifestyle

33

why do patients need to be fully informed when taking medication propylactically ?

daily medication for potentially 30 years
may have unpleasant side effects
also have to allow it time to work- 2 months

34

how much does prophylactic treatment ususally reduce migraines?

usually by about 50% but it may just be a short term solution

35

what beta blockers can be used and prophylactic treatment and what are their effects ?

propranolol, metaprolol, timolol and nadolol
propranolol causes more than an 50% reducton in migraine attacks in 35-60% of patients
has no effect on reducing severity of duration of attacks

36

what are the side effects of beta blockers ?

drowsiness
fatigue, lethargy
sleep disorders, nightmares
depression
memory disturbances
hallucinations
bronchoconstriction
cardiac failure
cold extremities
hypotension
exacerbation of heart failure
renal failure

37

what are the contraindications associated with beta blockers ?

asthma and hypertensio

38

what anticonvulsants are used as prophylactic treatment and what do they do ?

topiramate and sodium valporate
- only topiramate is licensed in UK
block voltage gated calcium cahnnels, increase GABA action at GABAa receptors and AMPA/KA antagonists

39

what are the side effects of topiramate ?

paraesthesia
fatigue
anorexia
nausea
taste disturbance
diarrhoea

40

what are the side effects of sodium valporate ?

mild to moderate nausea
vomiting
gastrointestinal distrss
infection
alopecia
tremor
asthenia
dizziness
somnolence

41

what tricyclic antidepressants are used as prophylactic treatment ?

amitriptyline
not licensed in UK
need much lower doses compared to depression treatment

42

what are the side effects of amitriptyline ?

sedation
drowsiness
dry mouth
weight gain
constipation
mania
dizziness
tachycardia
blurred vision
tremor
confusion
arterial hypotension
urinary retention
akathesia

43

what serotonin antagonists are used inn prophylactic treatment ?

methysergide and pizotifen
- have antihistamine and sertonin antagonistic effects
- some have anticholinergic effects
block serotonin 1, 2a and 2c
2nd line of medication

44

what are the side effects of pizotifen ?

increased appetite- weight gain
drowsiness
antimuscarinic activity- dry mouth
constipation
blurred vision

45

what are the contrainidcations of pizotifen ?

pregnancy
breast feeding
glaucoma
urinary retention
renal impairment

46

what are the side effects of methysergide?

rarely used now - only in hospitals
very dangerous side effects
- retroperitoneal fibrosis
- fibrosis of heart valves
- behavioural disturbances
- arterial spasm
can only be taken for 4 months before you have to have a month off