Diagnosis: Cluster Headache
This patient has cluster headache, and verapamil is the best prophylactic treatment, with subcutaneous sumatriptan or high-flow oxygen for acute attacks. 1, 2, 3
Clinical Diagnosis
The presentation is pathognomonic for cluster headache based on the International Headache Society criteria:
- Severe unilateral periorbital/orbital pain lasting 15-180 minutes (this patient reports ~1 hour) 1, 4, 5
- Ipsilateral autonomic symptoms: lacrimation (watery eyes) and rhinorrhea (runny nose) are classic features 1, 4, 5
- Attack frequency: The recurrent nature suggests episodic cluster headache with multiple attacks 4, 5
- Trigger sensitivity: Chemical odors (gasoline, acetone, tobacco, nail polish) are recognized cluster headache triggers 5
The normal neuroimaging appropriately excludes secondary causes, and no red flags are present (no fever, focal deficits, or progressive worsening). 1
Why Not Other Diagnoses?
Migraine is excluded because attacks last 4-72 hours (not 1 hour), patients prefer lying still in dark quiet rooms (not restless/agitated), and the prominent autonomic symptoms with short duration are incompatible with migraine. 6, 4
Tension-type headache is excluded because it presents with bilateral pressing/tightening pain of mild-to-moderate intensity without autonomic features. 1
Giant cell arteritis is excluded because this patient lacks the age criterion (>50 years), continuous dull aching pain pattern, jaw claudication, and systemic symptoms. 6, 4
Best Prophylactic Treatment
Verapamil is the first-line preventive treatment for cluster headache with the strongest evidence base. 2, 3
Verapamil Protocol:
- Start at 120-240 mg daily in divided doses 2, 3
- Titrate gradually up to 480-960 mg daily as needed for efficacy 2, 3
- Critical caveat: Obtain baseline ECG and monitor with repeat ECGs during dose escalation to detect PR interval prolongation or heart block 2, 3
Bridge Therapy While Verapamil Takes Effect:
Oral corticosteroids (prednisolone 60-100 mg daily tapered over 2-3 weeks) provide rapid relief while waiting for verapamil to become effective, which typically takes 2-4 weeks. 2, 3
Alternative Preventive Options:
- Lithium (600-900 mg daily with serum level monitoring) is effective but requires careful monitoring of renal function and thyroid function 2, 3
- Galcanezumab (300 mg subcutaneous loading dose, then 300 mg monthly) has excellent evidence specifically for episodic cluster headache 2, 3
- Topiramate (50-200 mg daily) and gabapentin (900-3600 mg daily) are possibly effective alternatives 2
Acute Treatment Recommendations
For breakthrough attacks during prophylaxis:
- Subcutaneous sumatriptan 6 mg provides relief within 10-15 minutes and is the most effective acute treatment 2, 3
- High-flow oxygen (100% at 12-15 L/min via non-rebreather mask for 15-20 minutes) is highly effective and has no contraindications 2, 3
- Intranasal zolmitriptan 5-10 mg is an alternative when subcutaneous administration is not feasible 2, 3
Critical Management Pitfalls to Avoid
Do not treat this as migraine with standard migraine preventives (propranolol, topiramate for migraine dosing) as cluster headache requires specific management strategies. 6
Do not overlook medication-overuse headache risk if the patient begins using acute treatments ≥10 days per month for triptans or ≥15 days per month for simple analgesics like acetaminophen. 6, 7
Do not delay verapamil initiation while pursuing unnecessary additional testing, as early effective prophylaxis significantly improves quality of life and reduces attack frequency. 5, 3
Monitor for cardiac conduction abnormalities with serial ECGs when using verapamil, especially at higher doses, as PR prolongation and heart block can occur. 2, 3