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Flashcards in pharmacology of headache Deck (21):
1

List drugs for abortive therapy of migraine

Dihydroergotamine, ergotamine, isometheptene, NSAIDs, tramadol, triptans

2

List drugs for preventing migraine

b-blockers, anticonvulsants, antidepressants, calcium channel blockers, NSAIDs, 5-HT2 receptor antagonists

3

List drugs for abortive therapy ofcluster headaches

DHE, ergotamine, glucocorticoids, lidocaine, oxygen, sumatriptan

4

List drugs for preventing cluster headaches

Lithium, methysergide, and verapamil

5

List drugs for abortive therapy of tension headaches

NSAIDs-Acetaminophen

6

List drugs for preventing tension headaches

TCADs (amitriptyline) - SSRIs

7

Which medications lead to overuse headaches

high risk [butalbital combinations, aspirin-acetaminophen-caffeine, opioids], moderate risk [triptans, ergots], low risk [NSAIDs]

8

Two phases of migraine attacks

• First phase is characterized by cerebral vasoconstriction and ischemia. Serotonin release (5HT) from neurons and platelets (PERIPHERAL MECHANISMS) that acts on 5-HT2 receptors contributes to this phase.
• Second phase is characterized by cerebral vasodilation and pain. Neurons in the trigeminal complex release the vasoactive peptides substance P [SP] and calcitonin gene-related peptide [CGRP] that trigger vasodilation and neuroinflammation of pial and dural vessels (sensory nerve discharge). This in turn stimulates nociceptive fibers of the trigeminal nerve that causes pain• First phase is characterized by cerebral vasoconstriction and ischemia. Serotonin release (5HT) from neurons and platelets (PERIPHERAL MECHANISMS) that acts on 5-HT2 receptors contributes to this phase.
• Second phase is characterized by cerebral vasodilation and pain. Neurons in the trigeminal complex release the vasoactive peptides substance P [SP] and calcitonin gene-related peptide [CGRP] that trigger vasodilation and neuroinflammation of pial and dural vessels (sensory nerve discharge). This in turn stimulates nociceptive fibers of the trigeminal nerve that causes pain

9

What is the initiating event of the first phase of a migraine

may be an abnormal discharge, set off by emotional or biochemical disturbances (CENTRAL MECHANISMS).

10

Importance of drug route in migraine meds

Effect of oral meds can be delayed by migraine-related decrease in GI motility and / or nausea-vomiting (consider use of anti-emetics [metoclopramide]). Onset is fastest via parenteral route (SC > NASAL > PO).

11

Use of NSAIDs/acetaminophen for migraine and MOA

mild to moderate episodes of migraine without nausea. Inhibit COX-2 which interrupts inflammatory pathway initiated by release of CGRP

12

Triptans- use, examples and MOA

Used as first line agents for moderate to severe migraine. Sumatriptan, zolmitriptan. Agonist of 5HT 1B/1D receptors causing vasoconstriction (1D), inhibition of vasoactive peptides (1B)

13

Triptans - absorption, distribution and duration

All available orally, sumatriptan and zolmatriptan available nasally, S given SC. Lipophilic, good brain penetration except for sumatriptan. Short half life

14

Triptans- adverse drug reactions and drug-drug interactions

Pregnancy category C, may cause Paresthesias, flushing, dizziness, drowsiness, chest tightness and rarely coronary vasospasm, angina, MI, stroke, death. Additive vasoconstriction with ergot alkaloids. Increased risk of seretonin syndrome with MAOIs (clonus, ANS changes, mental status change)

15

Examples of ergot alkaloids

Dihydroergotamine , ergotamine

16

Ergot alkaloids MOA

5HT 1B/D Agonist (less effective than triptans). More toxic (not first line). Only used if no response to triptans.

17

Ergot alkaloids routes, duration/onset

Ergotamine: Oral (increased absorption w/caffeine, otherwise poor availability) - sublingual - rectal; long duration

Dihydroergotamine: Intranasal-parenteral; rapid and reliable onset

18

Ergot alkaloids adverse reactions and DDIs

Can cause vascular occlusion and gangrene (via a-1 adrenergic vasoconstriction). May cause severe peripheral ischemia if used with non selective beta blockers

19

When is prophylactic treatment for migraines used

If severe, frequent (> 4/month), long lasting (> 12 h), or disabling

20

List prophylactic drugs use for migraines, examples

migraine prophylaxis: 1. Beta blockers (propranolol, first line). 2. Ca channel blockers (Verapamil, third line). 3. ACEIs (lisinopril) or ARBs.are second or third line. 4. Antidepressants (amitripyline, second line). 5. anticonvulsants (valproate first line and topiramate). 6. Botox (second line agent) 7. NSAIDS (short term). 8. Methysergide (serotonin receptor antagonist- 5HT2 blocker blocks serotonin mediated vasoconstriction that initiates the attack)

21

Dietary supplements used for migraine prophylaxis

riboflavin and feverfew