Sphenopalatine Ganglion (SPG) Block

Key facts

Who it is for

What the sphenopalatine ganglion is and why numbing it can stop a headache

The sphenopalatine (pterygopalatine) ganglion is the largest nerve cluster outside the skull. It sits in a small bony pocket behind the back of the nose, just below the eye socket. Three systems meet there: sensory fibers from the second division of the trigeminal nerve (cheek, upper teeth, palate, nose), parasympathetic fibers that widen blood vessels and produce tearing and a runny nose, and sympathetic fibers. In cluster headache and migraine the parasympathetic output through the ganglion is part of what drives the attack, which is why cluster attacks come with a tearing eye and a blocked nostril on the pain side. Local anesthetic on the ganglion quiets that circuit for a few hours, and repeated blocks appear to dampen it for longer.

Transnasal applicator technique (office). You lie on your back with your head tilted back. A soft, flexible applicator or thin catheter is passed gently along the floor of the nostril to the back of the nasal cavity, where only a thin layer of tissue separates it from the ganglion. Local anesthetic (usually 2–4% lidocaine or 0.5% bupivacaine) is dripped or sprayed onto that spot, 1–2 mL per side, and you stay lying down for 10–15 minutes while it soaks through. No needle passes through the skin, no X-ray is needed, and you can drive yourself home. Both sides are usually treated for migraine; the pain side alone for cluster headache and facial pain.

Infrazygomatic (needle) approach. For a more precise block, or before radiofrequency of the ganglion, a thin needle is passed under fluoroscopy through the cheek below the cheekbone into the pterygopalatine fossa, where contrast dye confirms the position and 1–2 mL of anesthetic is injected directly on the ganglion. This gives a more complete block at the cost of a needle, X-ray, a small risk of bleeding into the cheek, and a driver if sedation is used. It is also the route for pulsed radiofrequency when blocks work but do not last.

Series and frequency. For an active cluster attack or post-dural-puncture headache a single block is given and repeated once if needed. For cluster bouts and chronic migraine the studied protocol is a series: twice a week for 6 weeks, 12 treatments, with the neurologist tracking headache days. For facial pain, blocks are repeated as relief dictates, typically no more often than every 1–2 weeks.

What happens on procedure day

1. Check-in and a short review: your headache or facial pain score right now, your neurologist's request, medications taken today, and any nasal problems, nosebleeds or blood thinners.
2. You lie on your back on the exam table with a small pillow under your shoulders so your head tilts back. A tissue and a cup are within reach because some anesthetic drains into the throat.
3. A drop of lidocaine spray or gel numbs the nostril. The soft applicator is passed slowly along the floor of the nose to the back wall; you feel pressure and fullness, not sharp pain. Tell us if it hurts and we will adjust.
4. The anesthetic is delivered, 1–2 mL per side. A bitter taste at the back of the throat and numbness of the palate and upper teeth follow within a minute or two. The applicator stays in place, or is withdrawn and the process repeated, over 10–15 minutes.
5. You keep lying back for the soaking period, then sit up slowly. We ask you to rate the headache again before you leave; for an active cluster attack the response is often clear within 15 minutes.
6. You go home with a headache diary. No driver is needed for the transnasal block. For the infrazygomatic needle approach the steps are similar but on the fluoroscopy table, with skin cleaning, a lidocaine wheal on the cheek and contrast confirmation.

After the procedure

Day 0. Bitter taste, a numb palate and upper teeth, and a stuffy or runny nose on the treated side last 30 minutes to a few hours. Do not eat or drink hot liquids until the throat numbness has worn off (about 30–60 minutes) to avoid burns or choking. Some lightheadedness on sitting up is common; rest a few minutes. A small amount of blood-tinged mucus is normal. Avoid blowing your nose hard for the rest of the day.

Days 1–3. Relief from a single block often fades over one to a few days. Record headache days, intensity and rescue medication in the diary; your neurologist will use it. Mild nasal irritation can persist for a day or two.

Week 1–2 and through a series. Benefit in a series builds gradually; a first block that does little does not predict the series. Keep preventive medication going as prescribed and limit acute medication to fewer than 10 days a month so the blocks are not undone by rebound headache.

When we judge the response. For an active attack, within 15–30 minutes. For a series, at the midpoint (6 treatments) and the end (12), by headache days per month compared with your baseline. Call the same day for a nosebleed that does not stop with 15 minutes of pressure, fever, facial swelling, or a new severe headache unlike your usual one.

What the evidence shows

For cluster headache, SPG-directed treatment has the best support: the ganglion is a proven target (an implanted SPG stimulator aborted attacks in a randomized sham-controlled trial), and small trials and series of transnasal and infrazygomatic anesthetic blocks show they can abort attacks and shorten bouts; radiofrequency of the ganglion gives longer relief in chronic cluster patients who respond to blocks. For chronic migraine, a randomized sham-controlled trial of repeated transnasal blocks (12 treatments over 6 weeks) reduced headache pain and improved quality of life at the end of the series, with benefit fading over the following month; a smaller trial in acute migraine showed short-term relief. The American Headache Society lists SPG block among the peripheral procedures that can be used within a migraine plan, with the caveat that the evidence is modest and neurology should lead. For post-dural-puncture headache, retrospective series suggested the block could spare some patients an epidural blood patch, but a randomized blinded trial found no difference from placebo at 30 minutes; it is reasonable to try once before a blood patch, not a replacement for it. For trigeminal neuralgia and atypical facial pain, evidence comes from case series and small trials, with pulsed radiofrequency of the ganglion reported to give months of relief in responders. Gulf Coast Pain & Spine offers SPG blocks on neurology referral in Houston and Webster, and in Pearland when that office opens in November 2026; we do not manage migraine or cluster headache as a practice, and your neurologist stays in charge of the plan.

Alternatives and what comes next

For cluster headache the established treatments are high-flow oxygen and injectable sumatriptan for attacks, verapamil and short steroid courses for prevention, and a greater occipital nerve block with steroid, which has stronger trial evidence than SPG block for shortening a bout; many cluster patients get both. For migraine, preventive medication, CGRP-targeted drugs and onabotulinumtoxinA come first, and occipital nerve blocks are the more studied add-on. For facial pain, carbamazepine or oxcarbazepine and neurology evaluation come first; a positive SPG block response can lead to pulsed radiofrequency of the ganglion through the infrazygomatic route, which typically extends relief to months, or, for cluster headache, to referral for SPG stimulation or neurolysis at a headache center. For post-dural-puncture headache that persists after a block, an epidural blood patch is the definitive treatment. If a well-performed SPG block gives no relief, the ganglion is not driving your pain, and the occipital nerves and upper neck or the trigeminal system itself are examined next with your neurologist. Ask us whether we currently offer SPG blocks and which route we recommend for your situation.

Safety and preparation

• Blood thinners: the transnasal block is superficial and can usually be done on aspirin, clopidogrel, warfarin or a DOAC, with a slightly higher nosebleed risk. The infrazygomatic needle approach passes near the maxillary artery and follows ASRA guidance for intermediate-risk procedures, so those drugs are typically held for 2–7 days. Never stop a blood thinner on your own.
• Diabetes: no steroid is used in a standard SPG block, so blood sugar is unaffected.
• Infection or fever: an active sinus infection, cold with nasal congestion, fever above 100.4°F, or cold sores on the nose postpones the block.
• Allergies (contrast, steroid, local anesthetic): no contrast dye is used for the transnasal route; the needle route uses a small amount. Tell us about any reaction to lidocaine or bupivacaine so we can substitute.
• Pregnancy: the transnasal block uses no X-ray and small anesthetic doses and can be done when the neurologist and obstetrician agree; the needle route is deferred. Tell us if you are or could be pregnant.
• Sedation and driving: no sedation is used for the transnasal block and you may drive yourself. If the needle approach is done with sedation, bring a driver.
• Nose and sinus history: tell us about a deviated septum, nasal polyps, prior sinus or nasal surgery, frequent nosebleeds or use of nasal oxygen or CPAP; these may change the route or the side we treat.
• Eating and drinking: eat normally beforehand. Afterward, wait until throat numbness has passed (30–60 minutes) before drinking anything hot.

Risks and side effects

Frequently asked questions

Related care

Related treatments

Related conditions