Pharmacotherapy: Abortive

The optimal pharmacological approach to acute headache requires matching treatment to headache severity while monitoring for therapeutic response and adverse effects.

Mild Headache

First-line:

• Acetaminophen 650-1000 mg PO
• Ibuprofen 400-800 mg PO
• Naproxen sodium 550-825 mg PO
• Aspirin 1000 mg PO
• Caffeine 130-200 mg PO (can be combined with acetaminophen or aspirin)

Pearls:

• Oral route preferred for mild headaches
• Avoid acetaminophen over 4 grams daily
• NSAIDs increase risk of gastritis; use PPI if high risk
• Caffeine improves acetaminophen absorption

Moderate/Severe Headache

First-line abortive therapies:

• Triptans – selective 5-HT1B/1D agonists
• Sumatriptan 6 mg SC, 20-100 mg IN, 25-100 mg PO
• Rizatriptan 5-10 mg PO
• Eletriptan 20-80 mg PO
• Monitor for serotonin syndrome, avoid if on SSRIs
• Antidopaminergics – block dopamine to inhibit vomiting
• Metoclopramide 10 mg IV
• Prochlorperazine 10 mg IV + diphenhydramine 25-50 mg IV
• NSAIDs – inhibit inflammatory pathways implicated in migraine
• Ketorolac 15-30 mg IV
• Avoid if renal impairment or high GI bleed risk
• Opioids generally not recommended and demonstrate lower efficacy than other options

Second-line options:

• Magnesium sulfate 1-2 grams IV
• DHE 45 mcg/kg IV or SC
• Droperidol 0.625-2.5 mg IV

Status Migrainosus (>72 hours unrelenting headache)

• Metoclopramide 10 mg IV
• Prochlorperazine 10 mg IV
• Magnesium sulfate 2 grams IV
• Hydration with isotonic fluids
• Valproic acid 500-1000 mg IV
• Dihydroergotamine 1 mg IV, IM, IN
• Dexamethasone 10 mg IV
• Admit for trial of IV DHE infusion

Key Pearls:

• Use antiemetics if nausea/vomiting prominent
• Avoid basal stimulants like morphine due to risk of medication overuse headache
• Start low, go slow with dosing if elderly or debilitated
• Have high suspicion for secondary headache if poor treatment response

Migraine Cocktails

Migraine cocktails are a combination of medications given together to treat acute migraine headaches. Typical components include:

• Antiemetic – Metoclopramide 10mg IV or Prochlorperazine 10mg IV
• Relieves migraine-associated nausea and vomiting
• Exerts additional antimigraine effect by blocking dopamine
• Give with diphenhydramine 25-50mg IV to prevent extrapyramidal side effects
• NSAID – Ketorolac 15-30mg IV
• Inhibits synthesis of inflammatory prostaglandins involved in migraine
• Use lower 15mg IV dose to minimize risk of GI bleed
• Hydration – 1 liter isotonic fluids
• Replaces fluids lost from vomiting
• May have direct antimigraine effects
• Is not evidence-based and no longer recommended due to no impact on analgesia
• Magnesium sulfate – 1-2 grams IV
• NMDA receptor antagonist with potential migrainostatic effects
• Often given as add-on therapy or for refractory cases
• Dexamethasone 10mg IV
• Prevents recurrence of headache after ED discharge
• Avoid in uncontrolled diabetes or serious infections
• Avoid opioids as part of migraine cocktails due to concerns of medication overuse headache

Additional Pearls:

• Sumatriptan 6mg SC is more effective than cocktail components but has more adverse effects
• Oral triptan is reasonable option for milder cases with no vomiting
• Give antiemetic first to control vomiting then NSAID as tolerated
• Adjust components based on patient factors and treatment response
• Admit if status migrainosus unresponsive to cocktail therapy

Peripheral Nerve Blocks in Migraine Management

Types of Nerve Blocks

1. Occipital Nerve Blocks

• Targeting the greater occipital nerve, used for acute migraine treatment.
• Efficacy supported by a sham-controlled trial, with headache freedom achieved in 31% of patients receiving bilateral occipital nerve blocks compared to none in the sham group.
• Minimal adverse effects, with similar safety profiles between treatment and sham groups.

1. Sphenopalatine Ganglion (SPG) Blocks

• Intranasal devices facilitate topical application of local anesthetic to block the SPG.
• Anatomic research raises doubts about the effectiveness of this method due to the SPG’s location.
• Limited evidence suggests benefit in acute migraine, with one trial showing a 50% reduction in headache intensity at 15 minutes in 55% of patients treated with intranasal lidocaine.

Greater Occipital Nerve Blockade (GONB) Studies

1. Comparison with Metoclopramide

• A study of 99 patients comparing 0.5% bupivacaine GONB to 10 mg IV metoclopramide found GONB less efficacious in pain reduction at one hour.
• GONB patients required more rescue medication compared to the metoclopramide group.

1. Comparison with IV Dexketoprofen/Metoclopramide and Placebo

• GONB showed similar efficacy in pain reduction to the dexketoprofen/metoclopramide group but was superior to placebo.
• This study highlights the potential role of GONB in migraine treatment.

Clinical Considerations

• Contraindications to nerve blocks include allergy to local anesthetics, open skull defects, overlying skin infection, and pregnancy as a relative contraindication.
• Nerve blocks require skilled administration and may not be suitable in all clinical settings.

Additional Considerations

• Set realistic patient expectations that complete headache resolution is unlikely and goal is to reduce symptoms enough to function.
• Educate on importance of lifestyle modifications to reduce headache burden – diet, hydration, sleep, stress reduction.
• Review safe use of OTC analgesics for self-care of mild headaches with suggested quantities and durations.