What Should I Track in a Hemicrania Continua Diary?

To prepare for a headache specialist appointment for suspected hemicrania continua (HC), the most important pattern to track is whether you have a continuous, strictly one-sided background headache that never fully goes away, combined with superimposed episodes of severe pain (flares) ^[1][2]. Because the constant baseline pain is often mild to moderate, patients easily ignore it and only report their severe attacks. However, recording both the persistent low-grade pain and the severe flares is crucial for an accurate diagnosis ^[2][3].

A detailed headache diary helps your doctor distinguish hemicrania continua from similar conditions like chronic migraine or cluster headaches. However, a diary alone cannot confirm a diagnosis. Your doctor will use your tracking history alongside a physical exam, and sometimes imaging or supervised treatment trials, to safely identify your condition and rule out other causes ^[4].

Living with head pain that never fully stops can be exhausting, and it is completely normal to have trouble remembering every detail. Do the best you can to record the following patterns—even an imperfect diary is highly valuable to your doctor.

What to Track in Your Daily Headache Diary

Instead of just logging “I had a headache today,” break your tracking into the following specific categories.

1. Onset and History

Before starting daily tracking, note the origins of your pain:

• Start Date: When did this specific head pain begin?
• Onset Speed: Did it start suddenly or gradually?
• Duration: Has it been continuously present for more than three months? (A continuous headache for at least three months is a standard diagnostic criterion for HC ^[5][6]).

2. The Constant Baseline Pain

• Side and Location: Record which side of your head hurts. Is it always on the exact same side without ever switching? ^[1].
• Lack of Pain-Free Periods: Are there any moments where you are 100% pain-free? A defining feature of HC is the lack of completely pain-free intervals ^[1][2]. Note: It can be hard to know if you had pain while asleep. Simply record how you feel upon waking rather than assuming sleep was a pain-free interval.
• Intensity: Rate your everyday baseline pain on a scale of 1-10 separately from your severe flares ^[2].

3. The Severe Flares (Exacerbations)

• Timing and Duration: Record the exact start and stop times of sudden pain spikes. Flare length and frequency can vary widely in HC compared to other conditions like cluster headaches (which typically involve severe attacks lasting 15 to 180 minutes) ^[2][7].
• Peak Severity: Rate the peak intensity of the flare on a scale of 1-10.

4. Physical Signs During a Flare (Autonomic Features)

During a flare, look in the mirror and record any physical changes on the painful side of your face. These are called cranial autonomic symptoms ^[5] and include:

• Tearing or watery eye
• Eye redness (conjunctival injection) ^[8]
• Nasal congestion or a runny nose ^[9]
• Eyelid swelling, drooping eyelid, or a smaller pupil ^[8]
• Forehead or facial sweating

While these symptoms strongly support a trigeminal-autonomic diagnosis like HC, they can also occasionally happen during severe migraines ^[10]. Note if they are exclusively on the painful side.

5. Movement and Sensory Symptoms

• Agitation vs. Stillness: Do you feel physically restless, agitated, or have the urge to pace during a flare? Restlessness is common in HC ^[5]. While people having a migraine often prefer to lie still in a dark room, restlessness can occasionally occur in migraine too, so this is just one clue ^[10].
• Migraine-Like Features: Note any nausea, vomiting, sensitivity to light (photophobia), or sensitivity to sound (phonophobia). HC flares can mimic migraines by featuring these exact same symptoms, making careful tracking vital to tell them apart ^[3][5].

6. Medication Timing and Response

• Every Medicine and Dose Time: Log everything you take (including over-the-counter painkillers and supplements), the exact dose, time taken, and your response.
• Medication Overuse: Frequent use of acute painkillers can cause a secondary condition called “medication-overuse headache,” which can complicate your symptom pattern ^[11]. However, never abruptly stop prescribed medications without clinical advice.
• Indomethacin Response: A complete response to the prescription medication indomethacin is a required diagnostic feature for HC ^[6][12]. Do not self-test with indomethacin. A trial must be carefully supervised by a clinician because the drug carries serious risks, including stomach ulcers, gastrointestinal bleeding, kidney disease, and cardiovascular issues ^[13][14]. If a previous trial did not work, it might simply mean the dose or duration was wrong, which only your doctor can assess.

When to Seek Immediate Emergency Care

While tracking is important, do not wait for a routine specialist appointment if you experience any of the following “red flag” symptoms. Seek urgent or emergency medical care if you develop:

• A sudden, maximum-intensity “thunderclap” headache
• New weakness, numbness, confusion, or difficulty speaking
• Vision loss or severe eye pain
• Fever with a stiff neck
• A newly drooping eyelid or sudden change in pupil size, which can sometimes signal an urgent vascular issue (like a torn artery) rather than a routine HC symptom ^[15][4].
• A severe new headache during pregnancy or shortly after delivery
• A severe headache following a head injury

What to Bring to Your First Appointment

Ideally, bring 2 to 4 weeks of daily tracking, but do not delay your care just to finish a diary. Along with your diary, bring:

• A complete medication list: Include current prescriptions, over-the-counter drugs, past treatments that failed, and why they were stopped (for example, lack of benefit or severe side effects).
• Prior imaging: Bring the actual discs and reports of any previous brain MRIs or CT scans. Specialists often order an MRI to check for structural or vascular issues (secondary causes) that can mimic HC ^[4][15].