The supplied 46-year-old’s side-locked orbital pain, ipsilateral tearing and nasal congestion, and restlessness raise a trigeminal autonomic cephalalgia (TAC), with cluster headache among the possibilities. They do not establish cluster headache: the description does not give the exact untreated attack duration, number of attacks, daily frequency, or pain severity needed to check its criteria. And “less than two hours” is not precise enough to settle the subtype: the duration of each untreated attack and the number of attacks per day can point toward a different TAC.
The useful question is not simply whether this looks like a TAC. It is how the timing pattern changes the classification—and, in turn, the treatment plan.
Why the eye signs do not choose the subtype
Tearing and nasal congestion on the painful side are clues to a trigeminal-autonomic pattern, not a signature unique to cluster headache. TACs share pathways that link trigeminal pain signaling with cranial autonomic symptoms, so more than one syndrome can produce a painful, tearing eye or a congested nostril.
Restlessness helps characterize an attack but is not exclusive to cluster headache either. Paroxysmal hemicrania can also involve agitation. These features support the family resemblance; the attack clock helps separate the diagnoses.
Let the individual attack—not “under two hours”—set the differential
| Syndrome | Individual attack pattern | The distinguishing diagnostic move |
|---|---|---|
| Cluster headache | Untreated attacks last 15–180 minutes; frequency ranges from one every other day to eight per day. | At least five severe or very severe unilateral orbital, supraorbital, and/or temporal attacks are required, with an ipsilateral autonomic symptom or sign and/or restlessness or agitation. |
| Paroxysmal hemicrania (PH) | Severe unilateral orbital, supraorbital, and/or temporal attacks last 2–30 minutes and usually occur more than five times a day; lower frequency may occur during part, but less than half, of the active period. | At least 20 attacks are required, with an ipsilateral autonomic feature and/or restlessness; complete prevention with therapeutic-dose indomethacin is part of the criteria. |
| SUNCT/SUNA | Moderate or severe unilateral attacks last 1–600 seconds and occur at least daily. Pain may be a single stab, repeated stabs, or a saw-tooth pattern. | At least 20 attacks and an ipsilateral cranial autonomic feature are required. SUNCT requires both ipsilateral conjunctival injection and tearing; SUNA has no more than one of those two eye signs. |
| Hemicrania continua | One-sided pain is continuous, with exacerbations, rather than clearly separate pain-free attacks. | Requires unilateral pain for more than three months plus either an ipsilateral autonomic feature or restlessness/aggravation by movement, and an absolute response to therapeutic-dose indomethacin. |
The overlap between cluster headache and PH is a common trap: attacks lasting 15–30 minutes fit both duration ranges. A high daily frequency raises the possibility of PH, but it does not establish it by itself; the indomethacin response criterion matters. Conversely, a response to cluster-directed rescue treatment is not a formal diagnostic criterion for cluster headache.
In this illustrative vignette, “less than two hours” overlaps with part of the cluster range but also leaves open shorter attacks. If usual untreated attacks last at least 15 minutes, the patient has had at least five, the pain is severe or very severe, and the frequency fits, cluster headache becomes more plausible. If they last only a few minutes and occur many times daily, PH deserves closer attention; attacks lasting seconds to minutes raise SUNCT/SUNA and other brief facial-pain syndromes in the differential.
Ask what happens between attacks
Clarify whether the pain fully stops between episodes. A persistent one-sided background headache with flares is a different pattern from discrete attacks separated by pain-free intervals and should prompt consideration of hemicrania continua. Do not mistake a multiweek cluster period—a bout in which attacks recur—for one prolonged attack.
Ask about the most typical untreated episode: when the pain starts, when the attack fully ends, how severe it becomes, how often it recurs on an active day, and whether a milder residual ache remains. If treatment has shortened attacks, use the patient’s experience before treatment when available; do not ask the patient to delay rescue just to time an episode.
For very brief, triggered attacks, also ask what provokes them. SUNCT and SUNA can often be triggered without a refractory period, whereas trigeminal neuralgia commonly has a brief refractory period after an attack. Autonomic symptoms do not rule out trigeminal neuralgia, so a seconds-long shock should not automatically be assigned to the TAC group.
Let classification guide care—but do not use treatment response as a shortcut
The distinction matters at the bedside. For acute cluster attacks, guideline-supported options include oxygen and injectable sumatriptan. Those treatments can be appropriate when the clinical pattern supports cluster headache, but improvement does not replace the diagnostic criteria.
For PH, complete prevention at therapeutic doses of indomethacin is part of the classification. That is different from partial relief after an ordinary painkiller or a single dose. A clinician-directed therapeutic trial may help resolve the diagnosis when the attack pattern fits, with the patient’s individual risks considered.
Most importantly, do not let one memorable symptom—tearing, nasal congestion, or pacing—outvote the timeline. Record the duration and frequency, check for pain-free intervals, and keep the diagnosis provisional when the necessary details are missing.
Practical takeaways
- The supplied pattern raises a TAC, but “under two hours” alone does not establish cluster headache.
- Cluster attacks last 15–180 minutes; PH attacks last 2–30 minutes, creating a real overlap that frequency and indomethacin response help resolve.
- SUNCT/SUNA attacks last seconds to minutes; SUNCT requires both ipsilateral conjunctival injection and tearing.
- Ask whether pain is truly absent between attacks; continuous baseline pain with flares changes the differential.
- Use treatment to care for the patient, not as a substitute for classifying the attack pattern.
