Lec 66 Drugs to treat headaches Flashcards
What are classic prodrome symptoms of migraine?
mood change, fatigue, muscle tension, yawning, cognitive dysfunction
What is mech of neurogenic inflammation
trigeminal nerve activation –> release of CGRP/substance P/neurokinin A causes vasodilation, mast cell degranulation –> neurogenic inflammation within meninges –> pain
What is use of NSAIDs in migraine treatment?
non-specific acute treatment efficacy comparable to oral triptans dosing limited due to concern for renal toxicity non-sedating no increase in nausea safe in presence of vascular disease
What is use of neuroleptics in migraine treatment?
D2 antagonist to treat headache pain and migraine-associated nausea
Why shouldnt you treat migraine with opioids?
poor efficacy/paradoxical increased pain sensitivity b/c:
- pro inflammatory [degranulate mast cell], vasodilator, activate opioid receptors
- drug seeking behavior
- increase N/V
- poor efficacy
What is role of dopamine in migraine?
- prodomal symptoms are due to DA activation
What is effect of DA antagonists in migraine? side effects?
- antiemetic
- sedative
side effects = sedation and orthostatic hypotension
ex. metoclopramide
What are some names of D2 antagonists that are used to treat migraines?
given IV usually
- cholopromazine
- prochlorperazine
- droperidol
- metoclopramide
What are advantages/disadvantages of neuroleptics as migraine treatment?
- effective IV, reduce N/V
side effects:
- sedation, prolonged QT, orthostatic HTN,
extrapyramidal effects [dyskinesia]
dihydroergotamine: use, mech, effects, other
use: specific acute treatment to stop migraine
mech: agonist to 5HT-1D receptor
effects: vasoconstriction, nausea
contraindications: vascular disease, HTN, renal/hepatic failure, pregnancy
other: less specific for 5HT receptor compared with triptans
How does giving 5HT effect migraine?
IV 5HT relieves migraine but intolerable side effects
triptans use, mech, effects, other
use:
mech: 5HT1B/D (and some 1G) receptor agonist
effects:
other
What are the 3 mechs of action triptans in improving migraine symptoms?
- intracranial vessel vasoconstriction [5HT1B]
- peripheral neuronal inhibition [5HT1D]
- presynaptic dorsal horn stimulation [5HT1D] causes 2nd order brainstem neuronal inhibition
What are effects of triptan?
- reduce all aspects of migraine disability
- minimal or no sedation
- intrinsic antiemetic properties
What is use of opioids in migraine treatment?
emergency/rescue treatment
What is clinical triad of serotonin syndrome?
- mental status change
- autonomic hyperactivity [HTN, fever, shivering, diarrhea]
- neuromuscular abnormality [myoclonus, ataxia, hyperreflexia]
When should you consider preventative migraine treatment?
- headache freq > 6 per month
- headahce disability too often
- acute meds inneffective or contraindicated
- prolonged migraine aura or profound disability
What is mech of migraine prevention?
- raise threshold for migraine activation [inhibit CSD, sensitization, neurogenic inflammation]
- stabilize more reactive nervous system
What is use of antiepileptic drugs as migraine prophylaxis? which drugs?
valproate and topiramate
valproate: use, mech, effects, other
use: migraine prophylaxis or epilepsy
mech: block Na channels
effects: nausea, weight gain, tremor, alopecia, encephalopathy, hepatitis, pancreatitis
other: contraindicated in pregnancy
topiramate: use, mech, effects, other
Use: migraine prophylaxis or epilepsy
mech: block Na/Ca, increase GABA-A
effects:
other:
What should you use to treat pt with bipolar disorder and migraine?
valproate
What is effect of propanolol in migraine?
beta blocker = prophylaxis for migraine
How is efficacy of antidepressants as migraine treatment affected by presence/absence of depression?
not affected!
What is role of ca-channel antagonists in migraine?
exact mech uncertain
verapmil = L-type Ca channel blocker = most commonly used
may be good for migraine with prolonged aura or vestibular migraine
Onabotulinum toxin A: use, mech
Use: chronic migraine prophylaxis
mech: Inhibits release Ach at NMJ, blocks peripheral sensitization
