Headache Pharmacology - Bloom Flashcards
Which serotonin receptor is not a GPCR?
5-HT3 (ligand-gated cation channel)
Where is most serotonin found?
From what amino acid is serotonin derived? What enzyme is involved in the rate-limiting step in serotonin synthesis?
GI tract (only 2% in brain, mostly raphe nucleus)
Tryptophan. RLS: tryptophan hydroxylase
What two processes terminate the action of serotonin?
Serotonin is converted to what other hormone by the pineal gland?
Active reuptake by SERT or metabolism by MAO
Melatonin
Give the serotonin receptor primarily acted upon by the following serotonin agonists:
- 5-HT_1A
- 5-HT_2
- 5-HT_1B/D
- Buspirone
- LSD
- Triptans (example: sumatriptan)
What is the primary clinical use of the triptans?
Describe the triptan mechanism(s) of action in treating migraine headache
Migraine headache
Targets:
- Serotonin 1B/1D agonists
- Inhibit release of CGRP (vasoactive peptides)
- Promote vasoconstriction
- Block brainstem pain pathways
- Inhibit trigeminal nucleus caudalis
Give three drug classes that are alternatives to triptans for migraine termination (abortive treatment)
- Ergot alkaloids
- Steroids
- NSAIDs with caffiene
Among the triptans, what is special about Frovatriptan and Naratriptan
Long-acting. May be used for propohylaxis.
What are the main contraindications to triptan use?
Give some other common side effects
CI: Stroke, MI, uncontrolled hypertension, ischemic heart disease
AE: peripheral vasoconstriction, nausea and vomiting, angina, dizziness, flushing
Give (7) drug classes that might be used for migraine prophylaxis
- Antidepressants (Amitryptyline, Nortriptyline)
- Beta blockers (propranolol, atenolol)
- CCBs (verapamil, diltiazen)
- Anti-seizure medications (Divalproex sodium, valproic acid, gabapentin, pregabalin, topiramate, lamotrigine)
- Steroids
- Estrogens
- Long-acting triptans (frovatriptan)