neuro.cluster-headache.core.v1PRODUCTION

neuro.cluster-headache.core.v1

Cluster Headache

neurologysubacuteadult

Hard-required inputs

0 / 6

Care setting:

Encounter flow

10/12 authored

Canonical 12-phase frame with authored status for this dossier.

Current phase

Frame

Detailed

Confirm primary trigeminal autonomic cephalalgia scope; exclude SAH/dissection/pituitary apoplexy mimics (AAN 2010 PMID 27432623)

Inputs

Actions

Advance rule

Set

Advance when

thunderclap and structural mimics ruled out

Patient inputs (14)

age*demographic • CONTEXT

Age + sex shape DDx (CH male predominance, GCA in >50, trigeminal neuralgia bimodal) (ICHD-3 PMID 29368949)

attack_frequency_per_day*symptom • CONTEXT

Bout activity vs remission drives preventive vs bridge therapy; >5/day with very brief attacks → SUNCT (PMID 29368949)

attack_duration*symptom • DIFFERENTIAL

ICHD-3 requires 15–180 min untreated attacks to meet CH criteria; <30 min → paroxysmal hemicrania mimic; very short (<10 min, very frequent) → SUNCT/SUNA (PMID 29368949)

autonomic_features*symptom • DIFFERENTIAL

Ipsilateral autonomic features distinguish CH/TACs from migraine; presence + side-locked unilaterality is binding criterion (PMID 29368949)

episodic_vs_chronic*history • DIFFERENTIAL

not present

Episodic CH (bouts of weeks-months separated by remissions ≥3 mo) vs chronic CH (no remission ≥3 mo or <3 mo within 1 yr) branches galcanezumab eligibility (CGAL — galcanezumab approved for episodic only) (Goadsby NEJM 2019 PMID 31291515)

cad_or_uncontrolled_htn*history • TREATMENT

not present

Triptan absolute contraindication — pivot to octreotide 100 mcg SC or high-flow O2 only (AAN 2010 PMID 27432623)

current_medsmedication • CONTEXT

not present

Detect triptan overuse, MAOIs (24h washout), CYP3A4 interactions for verapamil (AAN 2010 PMID 27432623)

mri_brain_pituitaryimaging • INITIAL_WORKUP

not present

Exclude secondary causes at first presentation — pituitary adenoma can mimic CH; cavernous sinus lesions, AVM, dissection (AAN 2010 Robbins PMID 27432623)

lithium_levellab • MONITORING

Therapeutic monitoring on lithium prevention; target 0.6–1.2 mEq/L for chronic CH (AAN 2010 PMID 27432623)

bout_duration_so_farhistory • RISK_STRATIFICATION

not present

Status clusteribus = cluster bout ≥1 mo without remission requiring aggressive inpatient bridge (DHE per Raskin 1986 PMID 3520384)

hrvital • TREATMENT

Verapamil titration requires baseline HR + serial ECG (PR interval) (AAN 2010 PMID 27432623)

sbpvital • TREATMENT

Verapamil + steroid bridge can lower BP; uncontrolled HTN/CAD/PVD = triptan contraindication (AAN 2010 PMID 27432623)

creatininelab • TREATMENT

Lithium dosing + verapamil renal monitoring (AAN 2010 PMID 27432623)

tshlab • TREATMENT

Lithium thyroid monitoring baseline (AAN 2010 PMID 27432623)

* = hard-required. Engine cannot meaningfully run until these are filled.

Severity triggers (8)

8 need judgement

informationalseverechronic_cluster
Chronic cluster headache — no remission ≥3 mo or remissions <3 mo within last year (ICHD-3 PMID 29368949)
Trigger could not be auto-evaluated — needs clinician judgement.
informationalseverestatus_clusteribus
Cluster bout ≥1 mo without remission, requiring aggressive bridge therapy (Raskin Neurology 1986 PMID 3520384)
Trigger could not be auto-evaluated — needs clinician judgement.
informationalmoderateepisodic_cluster
Episodic cluster headache — bouts of weeks-to-months separated by remissions ≥3 mo (ICHD-3 PMID 29368949)
Trigger could not be auto-evaluated — needs clinician judgement.
informationalmoderatefirst_attack_ever_imaging_needed
First-ever cluster-pattern attack — pituitary adenoma + cavernous sinus lesion mimic (AAN 2010 PMID 27432623)
Trigger could not be auto-evaluated — needs clinician judgement.
informationalmoderateverapamil_pr_prolongation
PR interval >200 ms on serial ECG during verapamil titration (or 2nd/3rd degree AV block at any dose) (AAN 2010 PMID 27432623)
Trigger could not be auto-evaluated — needs clinician judgement.
informationalmoderatetriptan_contraindicated_use_octreotide
Triptan contraindication — CAD, uncontrolled HTN, pregnancy, PVD, recent MI/stroke, hemiplegic migraine, basilar migraine, severe hepatic/renal (AAN 2010 PMID 27432623)
Trigger could not be auto-evaluated — needs clinician judgement.
informationalmildsuncta_distinct
SUNCT (Short-lasting Unilateral Neuralgiform headache with Conjunctival injection and Tearing) / SUNA (with cranial Autonomic symptoms) — attacks <600 sec, very high frequency, prominent autonomic features (ICHD-3 PMID 29368949)
Trigger could not be auto-evaluated — needs clinician judgement.
informationalmildparoxysmal_hemicrania_indomethacin_responsive_distinct
Paroxysmal hemicrania — attacks 2–30 min, >5/day, with autonomic features; ABSOLUTE indomethacin response is diagnostic and therapeutic (ICHD-3 PMID 29368949)
Trigger could not be auto-evaluated — needs clinician judgement.

Workflow calculators

This dossier does not reference any calculators.

Recommended regimen

Cluster headache acute attack rescue (AAN 2010 / Cohen JAMA 2009 / ICHD-3)

axis: ch_acute_rescuestep 1 - Step 1 — Combination O2 + SC sumatriptan

Selected step "Step 1 — Combination O2 + SC sumatriptan" — Acute cluster attack

oxygen_high_flow
first line
inhaled_O2
100% O2 12–15 L/min via non-rebreather mask × 15–20 min • inhaled • PRN per attack (max: No effective max)
triggers: acute_cluster_attack
Cohen JAMA 2009 (PMID 19996400) — 78% pain-free at 15 min; first-line, no contraindication including in pregnancy/CAD
rxcui 7806
sumatriptan
first line
triptan
6 mg SC at attack onset • SC • q1h max 2 doses/24h (max: 12 mg/day SC)
triggers: acute_cluster_attack, no_CVD
Most rapid effect (15 min); SC route preferred over PO for speed (AAN 2010 PMID 27432623)
rxcui 37418
zolmitriptan
add on
triptan_IN
5–10 mg IN • IN • PRN (max: 10 mg/day IN)
triggers: SC_unavailable
Alternative when SC not available (AAN 2010 PMID 27432623)
rxcui 135775
octreotide
contraindication substitute
somatostatin_analog
100 mcg SC • SC • PRN per attack
triggers: triptan_contraindicated_CAD_uncontrolled_HTN_pregnancy_PVD
Triptan-CI pivot — Matharu Ann Neurol 2004 small RCT; AAN 2010 supports as alternative when triptans contraindicated (PMID 27432623)
rxcui 221130

outpatient playbook — drug actions (8)

1. home O2 prescription
100% O2 12–15 L/min NRB × 15–20 min PRN per attack • inhaled • PRN
trigger: New CH diagnosis
Cohen JAMA 2009 (PMID 19996400) — first-line acute
2. sumatriptan SC autoinjector
6 mg SC PRN per attack • SC • PRN max 12 mg/24 h
trigger: O2-inadequate attacks; no triptan CI
Rapid abort (AAN 2010 PMID 27432623)
3. prednisone bridge
60–100 mg PO daily × 5–10 d then 2–3 wk taper • PO • daily
trigger: Bout onset
Bridge to verapamil (AAN 2010 PMID 27432623)
4. verapamil titration
80 mg TID → titrate 80 mg/wk with ECG (PR <200 ms ceiling) → target 480–720 mg/d (often up to 960 mg/d) • PO • TID
trigger: Active bout / chronic CH
PREVA + AAN 2010 first-line preventive (PMID 27432623)
5. galcanezumab
300 mg SC monthly during bout • SC • monthly
trigger: Episodic CH phenotype only
CGAL — Goadsby NEJM 2019 (PMID 31291515); FDA-approved 2019 for episodic only. NOT effective in chronic CH per FOCUS PMID 32241175
6. lithium
300 mg BID → target level 0.6–1.2 mEq/L • PO • BID
trigger: Chronic CH OR verapamil failure
Effective in chronic CH; AAN 2010 (PMID 27432623)
7. topiramate
25 mg QHS → 100–200 mg/d • PO • BID
trigger: Verapamil intolerant
Second-line preventive (AAN 2010 PMID 27432623)
8. octreotide for triptan-CI attacks
100 mcg SC PRN • SC • PRN
trigger: CAD / uncontrolled HTN / pregnancy / PVD
Non-vasoconstrictor abortive (AAN 2010 PMID 27432623)

Auto-drafted A&P note

outpatient

Subjective

- Possible entry pathways: Severe unilateral orbital/periorbital pain (15–180 min) (ICHD-3 PMID 29368949); Ipsilateral lacrimation / conjunctival injection / rhinorrhea / ptosis / miosis (ICHD-3 PMID 29368949); Stereotyped attacks 1–8/day during a bout (ICHD-3 PMID 29368949).

Objective

- No vitals, labs, or imaging entered for this encounter.

Assessment

**Cluster Headache** (neuro.cluster-headache.core.v1).
Phenotype framing: Apply ICHD-3 criteria; episodic vs chronic vs probable CH; rule out paroxysmal hemicrania (indomethacin-responsive pivot), hemicrania continua (indomethacin pivot), SUNCT/SUNA (lamotrigine first-line), trigeminal neuralgia (carbamazepine), GCA (>50, ESR/CRP, biopsy) (ICHD-3 PMID 29368949)
Scope: Confirm primary trigeminal autonomic cephalalgia scope; exclude SAH/dissection/pituitary apoplexy mimics (AAN 2010 PMID 27432623)

No severity triggers fired against current inputs.

Plan

Regimen axis: **Cluster headache acute attack rescue (AAN 2010 / Cohen JAMA 2009 / ICHD-3)** — step "Step 1 — Combination O2 + SC sumatriptan".
1. oxygen_high_flow 100% O2 12–15 L/min via non-rebreather mask × 15–20 min inhaled PRN per attack (inhaled_O2, first line) — Cohen JAMA 2009 (PMID 19996400) — 78% pain-free at 15 min; first-line, no contraindication including in pregnancy/CAD
2. sumatriptan 6 mg SC at attack onset SC q1h max 2 doses/24h (triptan, first line) — Most rapid effect (15 min); SC route preferred over PO for speed (AAN 2010 PMID 27432623)
3. zolmitriptan 5–10 mg IN IN PRN (triptan_IN, add on) — Alternative when SC not available (AAN 2010 PMID 27432623)
4. octreotide 100 mcg SC SC PRN per attack (somatostatin_analog, contraindication substitute) — Triptan-CI pivot — Matharu Ann Neurol 2004 small RCT; AAN 2010 supports as alternative when triptans contraindicated (PMID 27432623)

Setting playbook (outpatient) — Primary site — verapamil titration to 480–960 mg/d with ECG q-step (PR <200 ms), transitional prednisone 60–100 mg/d × 5–10 d taper, galcanezumab 300 mg SC monthly for episodic, lithium for chronic, SPG stimulator referral for refractory chronic (AAN 2010 PMID 27432623)
5. home O2 prescription 100% O2 12–15 L/min NRB × 15–20 min PRN per attack inhaled PRN — New CH diagnosis (Cohen JAMA 2009 (PMID 19996400) — first-line acute)
6. sumatriptan SC autoinjector 6 mg SC PRN per attack SC PRN max 12 mg/24 h — O2-inadequate attacks; no triptan CI (Rapid abort (AAN 2010 PMID 27432623))
7. prednisone bridge 60–100 mg PO daily × 5–10 d then 2–3 wk taper PO daily — Bout onset (Bridge to verapamil (AAN 2010 PMID 27432623))
8. verapamil titration 80 mg TID → titrate 80 mg/wk with ECG (PR <200 ms ceiling) → target 480–720 mg/d (often up to 960 mg/d) PO TID — Active bout / chronic CH (PREVA + AAN 2010 first-line preventive (PMID 27432623))
9. galcanezumab 300 mg SC monthly during bout SC monthly — Episodic CH phenotype only (CGAL — Goadsby NEJM 2019 (PMID 31291515); FDA-approved 2019 for episodic only. NOT effective in chronic CH per FOCUS PMID 32241175)
10. lithium 300 mg BID → target level 0.6–1.2 mEq/L PO BID — Chronic CH OR verapamil failure (Effective in chronic CH; AAN 2010 (PMID 27432623))
11. topiramate 25 mg QHS → 100–200 mg/d PO BID — Verapamil intolerant (Second-line preventive (AAN 2010 PMID 27432623))
12. octreotide for triptan-CI attacks 100 mcg SC PRN SC PRN — CAD / uncontrolled HTN / pregnancy / PVD (Non-vasoconstrictor abortive (AAN 2010 PMID 27432623))

Non-pharmacologic actions:
- Avoid alcohol during bout (absolute trigger)
- Avoid daytime napping during bout (frequent trigger)
- Sleep hygiene — bout-onset signal to start verapamil + bridge
- Smoking cessation
- Headache neurology referral if 2+ preventive failures
- SPG stimulator implant referral if refractory chronic CH (Pathway CH-1, Schoenen Cephalalgia 2013 PMID 23314784)
- Occipital nerve stimulator (ONS) referral if SPG inaccessible
- gammaCore noninvasive vagal nerve stimulator (especially when triptans CI)

AVOID / contraindication checks:
- Triptans_avoid_in_uncontrolled_HTN_CAD_PVD_pregnancy (AAN 2010 PMID 27432623)
- Verapamil_serial_ECG_for_PR_QRS_and_heart_block_at_dose_escalation (AAN 2010 PMID 27432623)
- Lithium_renal_thyroid_monitoring_q3_mo (AAN 2010 PMID 27432623)
- Galcanezumab_episodic_CH_only_not_chronic (CGAL Goadsby NEJM 2019 PMID 31291515)
- Fremanezumab_NOT_effective_in_chronic_CH (FOCUS PMID 32241175)
- Steroid_short_course_only_to_avoid_AVN (AAN 2010 PMID 27432623)
- DHE_absolute_CI_with_triptan_within_24h_MAOI_pregnancy_CAD_PVD (Raskin 1986 PMID 3520384)
- Octreotide_for_triptan_contraindicated_attacks (AAN 2010 PMID 27432623)

Monitoring

Regimen monitoring:
- attack diary
- ECG PR <200 ms before each verapamil up titration (AAN 2010 PMID 27432623)
- lithium level q3 months (AAN 2010 PMID 27432623)
- creatinine TSH q3 months on lithium (AAN 2010 PMID 27432623)
- verapamil PR QRS check at each dose step (AAN 2010 PMID 27432623)
- DHE continuous cardiac monitoring during inpatient protocol (Raskin 1986 PMID 3520384)

Setting (outpatient) monitoring:
- Attack diary
- ECG before each verapamil up-titration (PR + QRS)
- Lithium level q3 mo (target 0.6–1.2 mEq/L)
- Creatinine + TSH q3 mo on lithium
- BP + HR q1–3 mo on verapamil

Follow-up plan: Headache neurology referral if refractory; bout-end taper plan; SPG / occipital nerve stimulator candidacy for refractory chronic CH (Schoenen Cephalalgia 2013 SPG-stim Pathway CH-1 PMID 23314784)
- Close-out criterion: follow-up cadence + return precautions set

Monitoring phase: Attack diary, ECG before each verapamil up-titration (PR <200 ms ceiling), lithium level + Cr + TSH q3 mo on lithium (AAN 2010 PMID 27432623)

Disposition

Current setting: outpatient — Primary site — verapamil titration to 480–960 mg/d with ECG q-step (PR <200 ms), transitional prednisone 60–100 mg/d × 5–10 d taper, galcanezumab 300 mg SC monthly for episodic, lithium for chronic, SPG stimulator referral for refractory chronic (AAN 2010 PMID 27432623)

Disposition criteria:
- Continue plan if attacks suppressed at acceptable cost (AAN 2010 PMID 27432623)
- Refer to headache neurology if 2+ preventive failures or severe ADRs
- Refer to neuromodulation interventionalist if refractory chronic CH

Escalation triggers (move to higher acuity):
- Refractory chronic CH (failure of verapamil + lithium + galcanezumab/topiramate) → headache specialty referral (AAN 2010 PMID 27432623)
- PR >200 ms or heart block on ECG → reduce verapamil dose (AAN 2010 PMID 27432623)
- Cluster mimic — attacks <30 min, very frequent → indomethacin trial (paroxysmal hemicrania pivot)
- Indomethacin-responsive continuous unilateral pain → hemicrania continua (distinct entity)
- SUNCT/SUNA pattern (very short <10 min, very frequent) → lamotrigine first-line, not cluster ladder
- Status clusteribus (bout ≥1 mo without remission) → inpatient DHE protocol (Raskin 1986 PMID 3520384)

Earlier-Return Triggers

Return-precaution thresholds (watch for):
- [SEVERE] Chronic cluster headache — no remission ≥3 mo or remissions <3 mo within last year (ICHD-3 PMID 29368949)
- [SEVERE] Cluster bout ≥1 mo without remission, requiring aggressive bridge therapy (Raskin Neurology 1986 PMID 3520384)
- [MODERATE] Episodic cluster headache — bouts of weeks-to-months separated by remissions ≥3 mo (ICHD-3 PMID 29368949)

Citations

- AAN 2010 Cluster Headache Practice Parameter (Robbins) + ICHD-3 + AHS 2016 + Goadsby 2025 nVNS CPG [PMID:29368949](https://pubmed.ncbi.nlm.nih.gov/29368949/)
- Cited evidence (PMID 27432623) [PMID:27432623](https://pubmed.ncbi.nlm.nih.gov/27432623/)
- Cited evidence (PMID 19996400) [PMID:19996400](https://pubmed.ncbi.nlm.nih.gov/19996400/)
- Cited evidence (PMID 31291515) [PMID:31291515](https://pubmed.ncbi.nlm.nih.gov/31291515/)
- Cited evidence (PMID 32241175) [PMID:32241175](https://pubmed.ncbi.nlm.nih.gov/32241175/)

Last reconciled with current guidelines: 2026-05-14.

References

AAN 2010 Cluster Headache Practice Parameter (Robbins) + ICHD-3 + AHS 2016 + Goadsby 2025 nVNS CPG — PMID:29368949
Cited evidence (PMID 27432623) — PMID:27432623
Cited evidence (PMID 19996400) — PMID:19996400
Cited evidence (PMID 31291515) — PMID:31291515
Cited evidence (PMID 32241175) — PMID:32241175