Chapter 33 Drugs for HA Flashcards
What is a Headache (HA)?
Triggered by stimuli such as stress, fatigue, acute illness, ETOH which can be mild to severe in nature
HA can be caused by? Or cannot be caused by?
HTN, hyperthyroid, tumor, infx, HEENT disorders
No identifiable cause either, could be just a migraine or cluster HA
What are some characteristics of a migraine HA?
THROBBING head pain
HIGHLY debilitating
Light SENSITIVITY
N/V
What are the TWO forms of a migraine HA?
w/ aura are preceded with visual symptoms
w/o aura (less common than w/ an aura)
What is the quick patho behind a migraine HA?
dilation & inflammation of intracranial blood vessels
VASODILATION LEADS TO THE PAIN!
What two compounds lead to a migraine HA?
calcitonin gene related peptide (CGRP) & serotonin (5-HT)
What does calcitonin gene related peptide (CGRP) do with migraines?
PROMOTES migraines
What does serotonin (5-HT) do with migraines?
SUPPRESSES migraines
Migraine HA treatment - aborting does what?
reduce the HA pain by ABORTING an ongoing attack
What is the first line therapy for ABORTING on going attacks of migraine HA?
Serotonin 1B/1D receptor agonists (triptans) are FIRST LINE THERAPY
I.e., zolmitriptan, naratriptan, etc…
What are the other different types of medications used to ABORT migraine HA?
Aspirin
Serotonin 1B/1D receptor agonists
Serotonin 1F receptor agonists
Ergot alkaloids
Calcitonin gene related peptide (CGRP) receptor antagonist/inhibitor
What Migraine HA tx prevents attacks from recurring and is considered as preventative?
Beta blockers (propanolol)
TCAs (amitriptyline)
Antiepiletpic drugs (divalproex)
Migraine HA Abortive tx does what?
How many times a week should you use this medication? Why?
eliminates HA and suppresses associated N/V
ORAL not effective if N/V (try IM/ inhalanet/ and suppository)
USE SHOULD BE LIMITED TO 1 OR 2 DAYS A WEEK TO PREVENT DRUG REBOUND HAs “aka med overuse HAs”
What antiemetic is the MOST PREFERRED DRUG for migraine HAs? Why?
Metoclopramide (reglan) decrease in gastric stasis (caused by migraine attack) which increase absorption > prochlorperazine (compazine)
Sumatriptan (imitrex) class of drug? Moa? Use? A/e? Contraindications?
Class - Serotonin 1B/1D receptor agonists FIRST LINE TX
MOA - binds to 5-HT1B/1D receptors on intracranial BVs and causes vasoconstriction decreasing perivascular inflammation
Use - aborting migraine HAs that are ongoing
A/e - heavy arms or transient CHEST pressure (coronary vasospasms - not a heart attack
Contraindications - pts with CAD, MIs/angina, HTN
Sumatriptan (Imitrex) drug interactions?
Ergot alkaloids or other triptans -> VASOCONSTRICTION (do not give within 24 hrs of each other)
MAOIs -> suppresses hepatic degradation = toxicity (give within a 2 weeks admin range)
SSRIs/SNRIs -> Serotonin syndrome (increases serotonin)
Serotonin 1B/1D Receptor Agonists end in?
-triptan (i.e., zolmitriptan, naratriptan, etc…)
Serotonin 1F Receptor Agonist? MOA? A/e?
NOT A -TRIPTAN but rather; -ditan (Lasmiditan)
MOA - does not cause vasoconstriction, binds with 5HT-1F receptor within trigeminal ganglia
potentially SAFER than 1B/1D d/t no vasoconstriction
A/e - Serotonin Syndrome with meds taken concurrently such as SSRIs and SNRIs
Ergot Alkaloids - Ergotamine Use? A/e?
Use - stops ONGOING migraine HAs second line therapy in patients that do not respond well to triptans
SHOULD NOT BE TAKEN DAILY OR LONG TERM D/T DEPENDENCE!
A/e - N/V
Can you overdose on Ergot Alkaloids - Ergotamine?
Yes! It is called Ergotism
OVERDOSE of Ergotamine causes Ergotism, which is a physical dependence on Ergotamine daily which can cause ischemia secondary to constriction of peripheral arteries and arterioles.
The extremities become COLD, PALE, and NUMB which can lead to GANGRENOUS limbs –> medical attention is needed
Pregnancy –> category X drug (induces fetal contractions and distress can occur)
Ergot Alkaloids - Dihydroergotamine Use? Pharmacokinetics? Admin?
2nd line treatment for terminating a migraine attack!
Similar to ergotamine except cause LITTLE N/V, and NO PHYSICAL DEPENDENCE is noted with MINIMAL vasoconstriction
NO ORAL ADMIN
Calcitonin Gene Related Peptide Receptor Antagonists - Urbogepant and Rimegepant
MOA, A/e, and Drug interaction?
This is a treatment not prevention!
MOA - blocks CGRP receptors from attaching as CGRP causes migraines!
A/e - N/v
Drug interactions - CYP3A4 inhibitors causes toxicity and CYP3A4 inducers would cause it to render ineffective
When is preventative tx considered for migraine HAs? What are preventative therapy types for migraine HAs?
Pts who have frequent attacks (3+ in a month), severe, OR have attacks that DO NOT response to abortive medications
Beta blockers (propanolol) - FIRST LINE OF PREVENTION
AVOID IN ASTHMATIC PTS AS IT CAN WORSEN ASTHMA
When would you administer Botulnium toxin B (Botox)?
For patients with greater than or equal to 15 HA days per month
What are cluster HAs? What kind of therapy is initiated?
Occur in a cluster, no aura, lasting 15 mins- 2 hrs with severe throbbing pain unilaterally near the eye with 1-2 attacks every day for 2-3 months.
Primary therapy is prophylaxis w/ tx of sumatriptan or O2
