Cluster Headache: Diagnosis and Treatment
Clinical Diagnosis
This patient's presentation is classic for cluster headache, not migraine. The unilateral burning pain behind the left eye lasting minutes to 2 hours, accompanied by ipsilateral lacrimation and facial fullness (likely representing eyelid edema), occurring most days of the week and triggered by alcohol, meets International Headache Society diagnostic criteria for cluster headache 1.
Key Diagnostic Features Present
- Severe unilateral pain localized to the retroorbital region (behind left eye) 1
- Duration of 15-180 minutes (her attacks last "a few minutes to 2 hours") 1
- Ipsilateral autonomic symptoms: lacrimation (watering of left eye) and facial fullness (likely eyelid edema) on the same side as pain 1
- High attack frequency: occurring "most days of the week" (cluster headache can have 1-8 attacks per day) 1
- Alcohol as trigger: alcohol is a well-known precipitant of cluster headache attacks 1
Why This Is NOT Migraine
Migraine typically presents with throbbing unilateral pain lasting 4-72 hours, worsening with routine activity, and associated with nausea/vomiting or photophobia/phonophobia 1. This patient's short-duration attacks (minutes to 2 hours) with prominent autonomic features (lacrimation, facial fullness) without nausea or photophobia are pathognomonic for cluster headache, not migraine 1.
Acute Treatment Algorithm
First-Line Abortive Therapy
Subcutaneous sumatriptan 6 mg is the most effective acute treatment for cluster headache attacks, providing pain relief within 15 minutes in 70-82% of patients 2. This should be administered at attack onset 2.
- Dosing: 6 mg subcutaneous at onset of attack, maximum of two doses in 24 hours 2
- Onset of action: Approximately 15 minutes, the fastest of all migraine-specific medications 2
- Efficacy: 59% achieve complete pain relief by 2 hours 3
Alternative Acute Options
High-flow oxygen (100% oxygen at 12-15 L/min via non-rebreather mask for 15-20 minutes) is equally effective as subcutaneous sumatriptan and should be offered as first-line therapy, particularly for patients with cardiovascular contraindications to triptans 1, 4.
Intranasal sumatriptan 20 mg can be used if subcutaneous administration is not feasible, though it has slower onset than subcutaneous formulation 2.
Contraindications to Triptans
Triptans are contraindicated in patients with ischemic heart disease, uncontrolled hypertension, cerebrovascular disease, or basilar/hemiplegic migraine 1, 2. At age 22 without mentioned cardiovascular risk factors, this patient is an appropriate candidate for triptan therapy 1.
Preventive Therapy
Preventive therapy should be initiated immediately given the high attack frequency (most days of the week) 1.
First-Line Preventive Medications
Verapamil is the first-line preventive medication for cluster headache, though this is not explicitly detailed in the provided guidelines 1.
For episodic cluster headache, short-term preventive therapy during the cluster period is appropriate 1.
Transitional Therapy
Corticosteroids (prednisone) can be used as transitional therapy while waiting for verapamil to take effect, providing rapid suppression of attacks within days 1.
Critical Management Principles
Medication-Overuse Headache Prevention
Limit acute treatment to no more than 2 days per week to prevent medication-overuse headache, which can transform episodic cluster headache into chronic daily headache 1, 2.
Alcohol Avoidance
Complete alcohol abstinence during cluster periods is essential, as alcohol reliably triggers attacks in cluster headache patients 1. This patient must be counseled that even small amounts of alcohol will precipitate attacks 1.
Urgent Referral Indications
Refer to neurology or headache specialist for:
- Confirmation of cluster headache diagnosis 1
- Initiation and titration of preventive therapy 1
- Management of refractory cases 1
Common Pitfalls to Avoid
Do not treat as migraine with oral NSAIDs or oral triptans alone, as these have insufficient speed of onset for the rapid-onset, short-duration attacks characteristic of cluster headache 1.
Do not prescribe opioids, which are ineffective for cluster headache and lead to dependency and medication-overuse headache 1, 2.
Do not delay preventive therapy in patients with frequent attacks, as untreated cluster headache causes severe disability and quality of life impairment 1, 4.