Pharmacology - Migraine & antimigraine remedies

Question 0

Give characteristics of a migraine headache

Answer 0

1 unilateral headache
2 pulsing/throbbing
3 moderate to severe pain
4 lasting 2-72 hours(more than 72 hours = status migranosus)
5 sensitivity to light, sounds and sometimes smells
6 increases during physical excersise
7 accompanied by autonomic nervous system symptoms (vomit, nausea).

Question 1

How many people suffer from migraine?

Answer 1

10-15% of population

Question 2

Describe migraine symptoms and stages.

Answer 2

1 Prodrome - days before attack, light and sound sensitivity
2 Aura - occur up to one hr before attack, visual disturbances
3 Headache - 2 to 72 hours, sever to moderate, unilateral
4 Postdrome - “migraine hangover”, depression, irritability and fatigue

Question 3

Patophysiology of migraine?

Answer 3

1 vascular theory - vasoconstriction of cerebral vessels during aura.
2 Brain theory - cortical spreading depression in patients w/aura
3 Sensory nerve theory - involvement of CGRP and serotonin receptor

Question 4

Nine migraine prophylaxis drugs?

Answer 4

1 Beta blockers(propanolol, metoprolol, timolol)
2 Clonidine(alpha2 agonist)
3 Ca channel blockers(e.g. nifedipine)
4 Topiramate(antiepileptic drug - agonism of GABA)
5 Valproic acid(antiepileptic drug - agonism of GABA)
6 Amitryptilyne(serotonin-NA reuptake inhibitor and TCA)
7 Venlafaxin(serotonin-NA reuptake inhibitor)
8 Forvatriptan(5-HT1 d/b agonist = vasoconstriction)
9 Botulinum toxin A(prevent CGRP release)

Question 5

Migraine headache management?

Answer 5

1 Analgesics - NSAIDs(aspirin, ibuprofen, paracetamol) + caffeine
2 Ergot alkaloids - 5-HT1 receptor partial agonist = vasoconstriction
3 Triptans - 5-HT1 d/b agonist, block CGRP and trigeminal nerve func.

Question 6

Name three triptans that crosses the BBB, has less side effects and that have improved bioavailability and duration of action?

Answer 6

1 Zolmitriptan
2 Naratriptan
3 Rizatriptan