Migraine Headaches: Tx and prevention - Fitz Flashcards
Migraine has a time course that starts with prodrome followed by the headache and finally a postdrome. What symptoms and signs are associated with each?
Prodome: Premoition 12-36 hours before headache: yawning, depression, lethargy, excitability, craving, distaste.
Headache: mostly unilatearl 4-72 hours. Photophobia, phonophibia, nausea, vomitting
Postdrome: exhaustion, fatigue
What class of drugs are used during the prodrome phase of migraine which goal is to rescue from/half a migraine attack.
Triptan - 5hT 1b/1d receptor agonists. must be given at the start of the prodrome phase.
Ergot alkaloids have also been considered, but they’re less selective and thus have more side effects.
During what phase of the a migraine time line are NSAIDS and acetaminophen typically used?
During the headache phase to relieve myalgia and symptoms that come after the onset of a headache.
What class of drugs are given during the asymptomatic phase to prevent the onset of a headache. usually taken even before the prodrome phase to prevent any onset.
- beta blockers: propranolol, timolol
- Tricyclic antidepressants : amitropylene, imipramine
- Anticonvulsants: topirimate, valproate
- Ca-channel blocker: verapamil
What are the physiological elements of a migraine attack?
vascular: cerebral and cranial vessels. meningela and dural arteries
Sensory nerves: CN V and ganglion and trigeminal nucleus caudalis
Brain: cortical spreading ‘wave’
Brainstem: distorted sensory input
Neurogenic inflammation: Neuropeptides (CGRP), Nitric oxide)
Serotonin receptors: 5HT1B/1D
Serotonin and its receptor are said to be key player in modulating migraine attack. Which serotonin receptor is located on vessel and which ones are located on neurons?
5HT-1B receptor on vessels
5HT-1D receptor on neurons
how does triptan help with prevention of the predrome of migraine?
Triptan by binding to 5HT-1B receptor lowers cAMP and thus stimulates vasoconstriction (opposes vasodilation which is associated with the symptoms). By giving triptan the serotonin deficit is being filled.
Triptan inhibits the release of CGRP and other neuropeptides from the peripheral end of CN V by stimulating the 5HT-1D receptors on pre-synaptic nerve terminals.
_ is an indoleamine that which is used at the beginning of a prodrome of a migraine headache. It has about 15% bioavailability and clearance is 1-2 hours. It is metabolized by monoamine oxidase-A
Sumatriptan - the prototype of the triptans.
Indolamines are analog of serotonin.
_ is an indolamine used for prevent the onset of migraine headache, taken at the prodrome phase. Relative to sumariptan, the oral version of this one has much better bioavailability (70%) and half life is about 6hrs.
Naratriptan
which Triptans to use is largely based on it’s delivery options. Which Triptans have the most delivery options and thus can be administered more than one way.
Sumatriptan (injectable subq, nasal spray, tablets)
Zolmitriptan (tablets, orally disintegrating tablets, and nasal spray)
What are the contraindications for triptans?
all triptans are modest vasoconstrictors of coronary, renal vessels (5HT1 receptors), thus pts with hx or suspicion of ischemic or vasospastic coronary disease, or other CV disorder and in pts with uncontrolled hypertension.
- Sumitraptan, rizatriptan and zolmitriptan are contraindicated in patients taking MAO inhibitors – they are metabolized by MAO
Can triptan be used with dihydroergatamine?
NO!!
What if happens triptan do not work to resolve prodrome symptoms?
You can use ergo alklaloids like dihydroergatamine. These are less specific, interacts with alpha-receptors, dopamine receptors, various 5HT receptors. and exhibit mexed action agonist, partial agonist and antagonistic effects. Use almost always leads to profound vasoconstriction in beds outside of cranial beds.
What is the consensus on the use of BOTOX for migraines?
It’s not the 1st 2nd, or 3rd line of therapy. Its approved for absolutely last resort in pt who did not respond to all other migraine medication.
What is the indication and mechanism as to why beta blockers are used for migraine prevention? what is the contraindication?
Propranolol or Timolol are FDA approved for migraine prevention. They have anxiolytic action and thus decrease sympathetic activity and blunts cortical spreading depresison. Contraindicated in asthma pts cuz of brochoconstriction effect
