Migraine Medications: Abortive and Preventive Therapy

Migraines require two treatment approaches: abortive therapy to stop an active attack and preventive therapy to reduce frequency and severity. This note summarizes the major drug classes, their mechanisms, key side effects, contraindications, and high-yield nursing considerations for the NCLEX.

Migraine Medications at a Glance

Abortive (Acute) Medications

• Triptans (Sumatriptan, Rizatriptan, Eletriptan): cause vasoconstriction; contraindicated in cardiovascular disease; take at first sign of migraine.
• CGRP antagonists / Gepants (Rimegepant, Ubrogepant): block CGRP protein; safe in vascular disease.
• Ergot alkaloids (Dihydroergotamine, Ergotamine): contraindicated in pregnancy and within 24 hours of a triptan; risk of ergotism.
• NSAIDs (Ibuprofen, Naproxen, Aspirin): first-line for mild to moderate pain; risk of GI bleeding.
• Antiemetics (Metoclopramide, Prochlorperazine): control nausea; can cause extrapyramidal symptoms.

Preventive Medications

• CGRP monoclonal antibodies (Erenumab, Fremanezumab, Galcanezumab): subcutaneous injection for chronic migraine; require refrigeration.
• Beta-blockers (Propranolol, Metoprolol, Timolol): first-line prevention; take 2–3 months for effect; contraindicated in asthma.
• Anticonvulsants (Topiramate, Valproate): Topiramate → weight loss, kidney stones; Valproate → weight gain, teratogenic.
• Antidepressants (Amitriptyline, Venlafaxine): Amitriptyline is sedating; Venlafaxine is less sedating.
• Botox (Onabotulinum toxin A): chronic migraine only; injections every 12 weeks.

Mnemonics

• Acute treatment — "NSAIDs": NSAIDs, Sumatriptan, Antiemetics, Dihydroergotamine.
• Prevention — "ABC": Antidepressants, Beta-blockers, Convulsants (anticonvulsants).

Mechanism of Action

1. Migraine pain begins when brain nerves release CGRP (calcitonin gene-related peptide), causing cranial vessels to dilate and become inflamed.
2. Triptans are serotonin agonists that cause cranial artery vasoconstriction.
3. CGRP antagonists block CGRP, the protein that causes vasodilation and transmits pain.
4. Ergot alkaloids stimulate serotonin, norepinephrine, and dopamine receptors to prevent vasodilation.
5. Beta-blockers prevent vasoconstriction by blocking epinephrine effects.
6. Anticonvulsants stabilize neuronal membranes and reduce cortical excitability.

Triptans (High-Yield)

• Key drugs: Sumatriptan (oral, nasal, injection), Rizatriptan (rapid onset), Eletriptan (oral).
• Side effects: chest tightness, dizziness, fatigue, nausea, injection-site reactions.
• Contraindications: ischemic heart disease, uncontrolled hypertension, hemiplegic migraine, use within 24 hours of another triptan or ergot, MAOI use within 14 days.
• Drug interactions: SSRIs/SNRIs increase serotonin syndrome risk; ergot alkaloids cause additive vasospasm.

Nursing Points

• Take at the first sign of migraine, during the mild pain phase.
• Limit to 2–3 times per week to prevent medication overuse headache.
• Investigate severe or persistent chest tightness.
• Injectable form works fastest for severe migraines.
• Triptan side-effect mnemonic — "CHEST": Chest tightness, Heaviness, Emesis, Sedation, Tingling.

Other Abortive Medications

Ergot Alkaloids

• Dihydroergotamine (DHE), Ergotamine.
• Contraindicated in pregnancy, cardiovascular disease, and with triptans within 24 hours.
• Ergotism: severe vasospasm causing cold, pulseless extremities, gangrene.
• Avoid with strong CYP3A4 inhibitors (azoles, macrolides, protease inhibitors).

NSAIDs

• Ibuprofen, Naproxen, Aspirin.
• First-line for mild to moderate migraines.
• Risk of GI bleeding with chronic use.

Antiemetics

• Metoclopramide, Prochlorperazine.
• Control nausea and vomiting.
• Can cause extrapyramidal symptoms (dystonia, akathisia).

CGRP Antagonists (Gepants)

• Rimegepant, Ubrogepant for acute treatment.
• Do not cause vasoconstriction — safe in vascular disease.
• Alternative for patients who cannot take triptans.

Preventive Medications

Beta-Blockers

• Propranolol, Metoprolol, Timolol.
• Take 2–3 months for full effect.
• Contraindicated in asthma, heart block, bradycardia.
• Side effects: fatigue, bradycardia, hypotension.

Anticonvulsants

• Topiramate: weight loss, paresthesias, cognitive dulling, metabolic acidosis, kidney stones, acute angle-closure glaucoma.
• Valproate: weight gain, tremor, alopecia, thrombocytopenia, hepatotoxicity. Teratogenic — avoid in pregnancy. Monitor LFTs.

Antidepressants

• Amitriptyline: sedating; anticholinergic effects (dry mouth, constipation).
• Venlafaxine: less sedating.
• Takes 4–6 weeks for effect.

CGRP Monoclonal Antibodies

• Erenumab, Fremanezumab, Galcanezumab — monthly subcutaneous injection.
• For chronic migraine prevention only.
• Require refrigeration and site rotation.

Botox (Onabotulinum toxin A)

• For chronic migraine (≥15 headache days/month).
• Injections every 12 weeks around head and neck.

Side Effects Summary

• Triptans: chest tightness, dizziness, fatigue → coronary vasospasm, serotonin syndrome.
• Ergot alkaloids: nausea, vomiting → ergotism, gangrene.
• Beta-blockers: fatigue, bradycardia → heart block, bronchospasm.
• Topiramate: paresthesias, weight loss → metabolic acidosis, glaucoma, kidney stones.
• Valproate: weight gain, tremor → hepatotoxicity, pancreatitis.
• Amitriptyline: dry mouth, constipation → cardiac arrhythmias.
• NSAIDs: GI upset → GI bleeding.

Pregnancy Safety

• Triptans: limited safety data.
• Ergot alkaloids: contraindicated — uterine contractions and fetal harm.
• Beta-blockers: may cause fetal bradycardia; use with caution.
• Valproate: avoid — causes neural tube defects.
• Topiramate: associated with cleft lip/palate; avoid if possible.
• NSAIDs: avoid in third trimester — premature closure of the ductus arteriosus.
• Acetaminophen is generally preferred in pregnancy.

Nursing Safety Rules & High-Yield NCLEX Notes

General Migraine Management

• Rest in a quiet, dark room during an attack.
• Identify triggers: stress, lack of sleep, fasting, bright lights, aged cheeses, MSG.
• Keep a headache diary.
• Maintain regular sleep and meals.

Key Nursing Points

• Triptans: take at first sign of migraine; limit to 2–3 times weekly to prevent rebound headache; monitor for chest tightness; watch for serotonin syndrome with SSRIs/SNRIs.
• Preventive meds: check heart rate with beta-blockers; ensure hydration and monitor vision with topiramate; check LFTs and pregnancy status with valproate; give amitriptyline at bedtime.
• Medication overuse headache: caused by using abortive drugs more than 2–3 times weekly; presents as daily headache; treatment requires withdrawal of the offending medication.
• Status migrainosus: migraine lasting >72 hours; treated with IV fluids, IV antiemetics, IV dihydroergotamine, IV valproate, or IV steroids.

POUND Mnemonic (Migraine Diagnosis)

• Pulsating quality
• 4–72 hOurs duration
• Unilateral location
• Nausea
• Disabling intensity

Patient Teaching

• Avoid triggers; do not skip meals.
• Keep rescue medication available.
• Seek emergency care for the worst headache of life.

Key Takeaways

• Migraine drugs split into abortive (acute attacks) and preventive (reduce frequency).
• Triptans are first-line abortive but cause vasoconstriction — contraindicated in cardiovascular disease and within 24 hours of ergots.
• CGRP antagonists (gepants) block pain proteins without vasoconstriction — safer for vascular patients.
• Beta-blockers, anticonvulsants, antidepressants, and CGRP monoclonal antibodies are mainstays of prevention; counsel that effect takes weeks to months.
• Watch for medication overuse headache (>2–3 abortive doses/week) and status migrainosus (>72 h).
• Use POUND for diagnosis and avoid valproate/topiramate/ergots in pregnancy.