Pharmacology - Agents for headaches and migraines

Question 1

Butalbital

Answer 1

Combination with other drugs for common headaches
Barbiturate
Incr GABAa channel opening–>CNS depressant

Question 2

Almotriptan

Answer 2

Triptan
Migraine treatment
Metab by cyto P450 and MAO-A

Question 3

Eletriptan, frovatriptan, naratriptan

Answer 3

Triptans
Migraine treatment
Metab by cyto P450, thus contraind with hepatic/renal impairment

Question 4

Rizatriptan, sumatriptan, zolmitriptan

Answer 4

Triptans
Migraine treatment
Metab by MAO-A, thus contraind when taking MAO inhibitors

Question 5

Triptans

Answer 5

Migraine treatment
Selective agonists of 5HT1b and 5HT1d
Inhib release of vasodilators–>vasoconstriction–>prevent abnormal dilation of intracranial blood vessels

Question 6

Sumatriptan adverse effect

Answer 6

Injection site reactions

Nasal preparation–>bitter taste

Question 7

Triptan adverse effects

Answer 7

Parasthesias
Asthenia and fatigue
Flushing
Feelings of pressure
Tightness
Pain in chest, neck, jaw
Drowsiness
Dizziness
Nausea
Sweating
coronary vasospasm-->contraind in pts with CAD

Question 8

Ergot and ergot alkaloids

Answer 8

Migraine treatment
Act on alpha and serotonin recep (5HT1b/5HT1d recep)
Agonist and partial agonist at CNS dopamine recep
Low bioavailability
Constrict most blood vessels
Contract uterus

Question 9

Ergotamine

Answer 9

Ergot and ergot alkaloid
Migraine treatment
Longer half life and longer acting than dihydroergotamine
Sublingual, oral, inhaler, suppository
IM or IV for severe attacks

Question 10

Dihydroergotamine

Answer 10

Ergot and ergot alkaloid
Migraine treatment
Shorter half life and shorter acting than ergotamine
Nasal spray
IM or IV for severe attacks

Question 11

Ergot and ergot alkaloid adverse reactions

Answer 11

Nausea, vomiting, leg weakness, muscle pain, numbness and tingling of fingers and toes
Toxic doses–>prolonged vasospasm–>limb gangrene and bowel infarction
Contraind in pregnancy, PVD, CAD, htn, impaired hepatic/renal function
Rebound headache with abrupt discontinuation

Question 12

Common headache treatment

Answer 12

OTC

Combination

Question 13

Migraine treatment

Answer 13

Triptans

Ergot and ergot alkaloids

Question 14

Migraine prevention

Answer 14

Antihypertensives - b blockers, CCBs
Antidepressants - TCAs, MAOIs, serotonin recep antagonists
Antiepileptic - topiramate, gabapentin, valproic acid
Methysergide

Question 15

B blockers

Answer 15

Migraine prevention
Only antihypertensive drug indicated for migraine prophylaxis
Several weeks for onset

Question 16

CCBs

Answer 16

Migraine prevention
Inhib Ca entry-->relaxation of vasc smooth muscle and vasodilation
Efficacy for migraine prophylaxis weak
Off label
May dev tolerance

Question 17

Propranolol, timolol, metoprolol, nadolol, atenolol

Answer 17

B blockers

Migraine prevention

Question 18

Verapamil

Answer 18

CCB

Migraine prevention

Question 19

Tricyclic antidepressants (TCAs)

Answer 19

Migraine prevention
Off label
Sedating

Question 20

Amitriptyline, nortriptyline, imipramine, doxepin, protriptyline

Answer 20

TCAs
Migraine prevention
Amitriptyline most common and efficacious

Question 21

Monoamine oxidase inhibitors (MAOIs)

Answer 21

Migraine prevention

Off label

Question 22

Phenelzine

Answer 22

MAOI
Migraine prevention
Substantial side effects
Questionable efficacy

Question 23

Serotonin receptor antagonists

Answer 23

Migraine prevention
Block 5HT2 and 5HT3 recep
Off label

Question 24

Mirtazapine

Answer 24

Serotonin recep antagonist

Migraine prevention

Question 25

Topiramate

Answer 25

``` Migraine prevention Blocks voltage Na channels Activates hyperpol K current Enhances GABAa Blocks AMPA ```

Question 26

Topiramate adverse effects

Answer 26

Somnolence, fatigue, wt loss, nervousness

Question 27

Gabapentin

Answer 27

Migraine prevention | No biotransformation

Question 28

Gabapentin side effects

Answer 28

Somnolence, dizziness, ataxia, fatigue | Usually subsides after 2wks of use

Question 29

Valproic acid

Answer 29

Migraine prevention Interfere with NMDA and GABA signaling Extensive metab by liver

Question 30

Valproic acid adverse effects

Answer 30

GI symptoms, sedation, ataxia, tremor | Serious rare ones are pancreatitis, hyperammonemia, teratogenic, fulminant hepatitis

Question 31

Methysergide

Answer 31

``` Migraine prevention Ergot derivative Mixed agonist/antagonist on serotonin recep No benefit during acute attack Not available in US ```

Question 32

Methysergide side effects

Answer 32

Inflammatory fibrosis and dependence (req tx interruption)

Question 33

Tension headache treatment

Answer 33

Amitriptyline

Question 34

Cluster headache treatment

Answer 34

Abortive: sumatriptan Preventive: verapamil, lithium, prednisone, indomethacin, topiramate, frovatriptan