Flashcards in Exam 4 Migraine medications Deck (24):
What is the role of serotonin in pain modulation?
-Serotonin (5-HT) receptors are important for pain modulation
_especially chronic pain
_receptors are found pre-synaptically and post-synaptically
_ many different receptors subclasses
What is the role of Serotonin and Serotonergic Neurons in pain modulation?
-in platelets= causes vasoconstriction
-in enterochromaffin cells in gut mucosa
--in periaqueductal gray (PAG)
--modulates nociception on a spinal level
--stimulation ***produced analgesia in midbrain
--MOST projections from PAG are tryptaminergic
--Dorsal raphe nuclei
--ALL laminae of dorsal horn
*****modulates pain/ nociception in descending pathways
What the role of 5- HT in pain modulation?
-Associated w/ psychiatric disorders
--learned this roll when LSD (hallucinogen) was shown to antagonize (block) 5-HT function
--Drugs that affect 5-HT system are used as treatments for these disorders
What are the known that 5-HT is involved in many behavioral and psychiatric disorders?
What are the drugs that affect 5-HT transmission?
5) antimigraine agents
6) atypical antipsychotics
7) appetite suppressants
8) Other drugs are assumed to affect 5-HT receptors because they influence conditions linked to 5-HT dysregulation= migraine
What is the correlation with Migraine and 5-HT?
-Data supports that migraine is caused by chronic 5-HT dysregulation
-in people w/ migraines:
● Increased 5-HIAA(metabolite) of 5-HT in urine
● Increases in plasma 5-HT
● decreases in plasma 5-HT
● Increases in 5-HIAA content in CSF
● PET scans show increased blood flow in highly serotonergic dorsal raphe nucleus during a migraine
What are the several classes of medications that can be used to manage migraines?
1) Ergot derivatives
3) isometheptene (Midrin)
What are Ergot Derivatives?
-constricts peripheral and cranial blood vessels
--partial agonist and/or antagonist activity against
***Inhibits depolarization of dural blood vessel-associated nociceptors
**Possibly blocks neurogenic inflammation through pre junctional inhibition of neuropeptide release
--produces depression of central vasomotor centers
--highly active uterine stimulant
What is Ergot Derivatives used for?
“abort” migraine= taken at onset of migraine attack
-take early in onset because absorption + distribution are impaired as gastric symptoms of migraine INCREASE
-addition of caffeine speed
s gastric absorption getting medication into system more rapidly
The two kinds _______ and ___________
(tablet or suppository form)
-side effects: ________damage, ________
-Alpha-adrenergic blocker that directly _____ vascular smooth muscle to__________peripheral and cerebral vessels
-______ antagonist at dopaminergic receptors
-partial agonist/antagonist for _______receptors
-given parenterally: IV, IM, SC, _____
-_____ half life: chronic migraine, unresponsive migraine
***ergotamine and caffeine (Cafergot, Migergot)
- blood vessel damage
- 5-HT receptors
Selective agonists of_________ and _____ receptors in cranial arteries
-causes __________ and reduces ___________
○ also provides relief from _____= antiemetic
○ sumatriptan was _____ drug in this class
- 5-HT 1B
- 5-HT 1D
-reduces neurogenic inflammation
What are the Preparations for triptans?
end in “triptan”
■ sumatriptan (Imitrex,Sumavel, DosePro)
■ naratriptan (Amerge)
■ zolmitriptan (Zomig)
■ rizatriptan (Maxalt)
■ frovatriptan (Frova)
■ eletriptan (Relpax)
■ almotriptan (Axert)
What is isometheptene (Midrin) ?
-also contains acetaminophen + dichloralphenazone
--dichloralphenazone= mild ***tranquilizing effect
-Used for migraines + tension headaches
- MUST be taken at onset; delay DECREASES efficacy
What are antiemetics?
--What do they control?
-Phenothiazine derivatives **(antipsychotics)
***Control nausea and gastric irritation associated with migraine.
-Tablet, suppository and parenteral forms
-Antagonists of D2 receptors
***May cause extrapyramidal effects
What are the Preparations for antiemetics?
1) ***prochlorperazine (Compro)
2) ***metoclopramide (Reglan, Metozolv)
3) ***promethazine (Phenergan, Phenadox, Promethegan)
4) trimethobenzamide (Tigan)
What are the several classes (8) of medications that can be used for migraine prophylaxis?
1) Tricyclic antidepressants
3) Selective 5-HT and NE reuptake inhibitor
4) Beta blockers
5) Antiseizure medications
6) Calcium channel blockers
Describe Tricyclic antidepressants (for migraine prophylaxis)
-Down regulates 5 HT receptors that are associate w/ excitatory perivascular inflammation; inhibits repute of BOTH 5-HT and NE
Describe SSRI's (for migraine prophylaxis)
Inhibits repute of 5-HT
Describe Selective 5-HT and NEW eruption inhibitors (for migraine prophylaxis)
venlafaxine (Effexor); also modulates anxiety
Describe **Beta blockers (for migraine prophylaxis) ?
-Unknown mechanism : vasoactivity
1) propranolol (Inderal)
2) nadolol (Corgard)
3) atenolol (Tenormin)
Describe **Antiseizure medications (for migraine prophylaxis) ?
Describe **Calcium channel blockers (for migraine prophylaxis) ?
-verapamil (Calan)= interferes w/ release of Ca++ dependent release of substance P (pain modulatory substance) and other neurotransmitters
Describe NSAIDS (for migraine prophylaxis) ?
***indomethacin (Indocin) = anti-inflammatory analgesic; alters cerebral blood flow w/o inducing vasospasm
-able to modulate cerebral blood flow thru nitric oxide pathway