Nerve Blocks for Migraine
Peripheral nerve blocks are a practical, in-office procedural option for migraine management. The greater occipital nerve (GON) block is by far the most studied and commonly performed. Nerve blocks serve multiple roles: bridging therapy while awaiting preventive onset, acute treatment for prolonged attacks, and adjunctive prevention in refractory patients. They are safe, fast, and can be repeated.
Bottom Line
- GON block is the workhorse — reduces migraine frequency and can abort ongoing attacks within 15-30 minutes
- Level B evidence (AHS) for GON block in migraine prevention
- Agents: Bupivacaine 0.5% (longer acting, preferred) or lidocaine 2%. Adding corticosteroid is debated.
- Best uses: Bridging therapy (e.g., starting a preventive), status migrainosus, refractory migraine, and patients who want to reduce medication use
- SPG block (sphenopalatine ganglion) via intranasal approach is emerging as an option for acute migraine and cluster headache
- Safe in pregnancy — one of the few procedural interventions available for pregnant migraine patients
Greater Occipital Nerve (GON) Block
Anatomy
The GON arises from the C2 dorsal ramus, ascends through the semispinalis capitis and trapezius, and becomes subcutaneous just below the superior nuchal line. It provides sensory innervation to the posterior scalp from the vertex to the occiput. It converges on the trigeminal nucleus caudalis in the upper cervical spinal cord, providing the anatomic basis for its role in headache treatment.
Evidence
- Ambrosini et al. (2005): RCT of GON block with suboccipital steroid injection vs placebo in chronic migraine — reduced headache frequency at 4 weeks
- Inan et al. (2015): GON block with bupivacaine vs saline in episodic migraine — migraine days reduced by 4.5 vs 1.3/month (p<0.01) at 1 month
- Dilli et al. (2015): Systematic review of 9 studies — GON block provides short-term benefit in migraine and cluster headache; evidence is moderate quality
- AHS position statement: Level B evidence for GON block in migraine prevention
Technique
GON Block: Step-by-Step
- Landmark: Palpate the occipital protuberance (inion). The GON is located approximately one-third of the distance from the inion to the mastoid process, just medial to the occipital artery (which can often be palpated)
- Preparation: Clean the area with alcohol. No local anesthetic of the skin is necessary.
- Needle: 25-gauge, 1.5-inch needle
- Injection: Advance the needle perpendicular to the skull until contact with the periosteum, then withdraw 1-2 mm. Aspirate to confirm no vascular entry. Inject 2-3 mL of anesthetic.
- Fan technique: Some practitioners redirect the needle slightly medially and laterally, depositing additional small volumes to cover the nerve's variable location
- Bilateral: For migraine, blocks are typically performed bilaterally regardless of headache laterality (bilateral trigeminal convergence)
Agents
| Agent | Concentration | Onset | Duration of Block | Notes |
|---|---|---|---|---|
| Bupivacaine | 0.5% | 5-10 min | 4-8 hours (block); clinical benefit may last weeks | Preferred for longer duration; most commonly used in practice |
| Lidocaine | 1-2% | 2-5 min | 1-3 hours (block); clinical benefit may outlast block | Faster onset; useful when rapid relief is needed |
| Mixture | 1:1 lidocaine 2% + bupivacaine 0.5% | 2-5 min | Intermediate | Combines rapid onset (lidocaine) with longer action (bupivacaine) |
Adding Corticosteroid
- Common practice to add methylprednisolone 40 mg or dexamethasone 4 mg to the local anesthetic
- Evidence is mixed: Some RCTs show added benefit of steroid (longer duration of effect at 4 weeks); others show no difference vs local anesthetic alone
- Rational approach: Use steroid for the first 1-2 blocks or for patients with occipital neuralgia/tenderness; omit for repeat blocks to avoid steroid side effects (skin atrophy, alopecia at injection site)
- Limit steroid-containing blocks to no more than every 3 months at the same site
Other Nerve Blocks
| Nerve | Location | Indication | Notes |
|---|---|---|---|
| Lesser occipital nerve (LON) | Posterior to the mastoid, along the posterior border of the sternocleidomastoid | Occipital headache with lateral predominance; occipital neuralgia | Often performed with GON block as part of a combined occipital block |
| Supraorbital nerve | Supraorbital notch/foramen (medial orbit rim) | Frontal-predominant migraine; supraorbital neuralgia | Use 0.5-1 mL of local anesthetic; avoid intravascular injection near the orbital rim |
| Supratrochlear nerve | Medial to supraorbital notch, along medial brow | Medial frontal headache; often blocked with supraorbital nerve | Small volume (0.3-0.5 mL); superficial injection |
| Auriculotemporal nerve | Anterior to the ear, superficial temporal artery (palpable) | Temporal-predominant migraine; post-procedural headache | 1-2 mL superficially; avoid the temporal artery |
Combined Block Approach
- For refractory migraine or status migrainosus, many headache specialists perform a combination block targeting GON + LON + supraorbital + supratrochlear + auriculotemporal nerves bilaterally
- Total volume: approximately 15-20 mL of local anesthetic across all sites
- This provides comprehensive sensory blockade of the trigeminal (V1, V3) and cervical (C2-C3) territories
- Can be performed as an alternative to IV infusion therapy for ED presentations
Sphenopalatine Ganglion (SPG) Block
The SPG is a parasympathetic ganglion in the pterygopalatine fossa with connections to the trigeminal nerve and the trigeminovascular system. It can be accessed non-invasively via the intranasal route.
Technique
- Intranasal approach: A thin, flexible catheter (e.g., Tx360 device, SphenoCath, or cotton-tipped applicator) is inserted along the nasal floor and advanced to the posterior nasal wall, adjacent to the middle turbinate
- Agent: 0.3-0.5 mL of lidocaine 4% or bupivacaine 0.5% is deposited at the SPG location
- Duration: Takes 10-15 minutes; patient may have transient bitter taste in the throat
Evidence
- Cady et al. (2015): Repetitive intranasal SPG blockade with bupivacaine (twice weekly for 6 weeks) in chronic migraine — reduced headache days vs placebo at 1 and 6 months
- Binfalah et al. (2018): Systematic review of 10 studies — SPG block provides short-term benefit for migraine and cluster headache; evidence quality is low to moderate
- Most useful for acute migraine relief and as a bridge therapy; less evidence for long-term prevention
Clinical Indications
| Scenario | Preferred Block | Rationale |
|---|---|---|
| Bridging therapy (starting a preventive, awaiting CGRP mAb onset) | GON block every 4 weeks | Provides immediate relief while preventive takes effect |
| Status migrainosus | Combined block (GON + frontal nerves) or SPG | Can break a prolonged attack without IV medications |
| Refractory migraine (failed multiple preventives) | GON block as adjunct | Adds a non-pharmacologic layer to multi-modal treatment |
| Pregnancy | GON block with bupivacaine (no steroid) | One of the safest procedural options in pregnancy; no systemic effects |
| Occipital neuralgia | GON + LON block with steroid | Diagnostic and therapeutic; response supports the diagnosis |
| Cluster headache (transitional) | GON block with steroid or SPG block | Can shorten a cluster bout while bridge/preventive therapy takes effect |
Frequency and Safety
- Local anesthetic alone: Can be repeated every 2-4 weeks as needed; no significant cumulative risk
- With corticosteroid: Limit to every 3 months at the same site to avoid skin atrophy and local tissue damage
- Adverse effects: Injection site pain (most common), transient numbness of the posterior scalp, lightheadedness, vasovagal episode (rare), local alopecia (rare, with repeated steroid use)
- Serious complications: Extremely rare. Intravascular injection (aspirate first), local infection (use clean technique), allergic reaction to anesthetic (rare)
References
- Inan LE, et al. Greater occipital nerve blockade for the treatment of chronic migraine: a randomized, multicenter, double-blind, and placebo-controlled study. Acta Neurol Scand. 2015;132(4):270-277.
- Ambrosini A, et al. Suboccipital injection with a mixture of rapid- and long-acting steroids in cluster headache: a double-blind placebo-controlled study. Pain. 2005;118(1-2):92-96.
- Dilli E, et al. Occipital nerve block for the short-term preventive treatment of migraine: a randomized, double-blinded, placebo-controlled study. Cephalalgia. 2015;35(11):959-968.
- Cady R, et al. A randomized, double-blind, placebo-controlled study of repetitive transnasal sphenopalatine ganglion blockade with tx360 as acute treatment for chronic migraine. Headache. 2015;55(1):101-116.
- Blumenfeld A, et al. Procedures for the treatment of headache: a position statement from the American Headache Society. Headache. 2013;53(10):1583-1596.
- Ashkenazi A, et al. Peripheral nerve blocks and trigger point injections in headache management. Headache. 2010;50(6):953-969.