A headache diary is a prospective record of headache days, symptoms and medication use. It can give you and a clinician more specific information than trying to remember several weeks at once. It does not diagnose a headache disorder, identify a trigger automatically or prove that a treatment worked.
What official guidance recommends
The UK National Institute for Health and Care Excellence, NICE, recommends considering a headache diary to record headache frequency, duration and severity, monitor headache interventions and support discussion about the disorder and its impact.
For diagnostic use, NICE advises recording:
- headache frequency, duration and severity;
- associated symptoms;
- all prescribed and over-the-counter headache medication;
- possible factors that preceded the headache;
- the relationship with menstruation when relevant.
NICE recommends recording for at least eight weeks when a diary is used to support diagnosis. That is a clinical guideline, not a promise that every pattern will become clear within eight weeks. Ask your clinician what period and level of detail they need.
What diary studies found
A prospective observational study from the Leiden Headache Clinic included 596 referred patients who completed an electronic diary on at least 80% of days for a minimum of one month. In 484 people diagnosed with migraine by a physician, monthly self-estimates differed from diary results by an absolute mean of 4.7 migraine days, 6.2 non-migraine headache days and 4.3 acute-medication days.
The diary and questionnaires were also tested as part of automated migraine screening. One screening approach was highly sensitive but had only 17% specificity; adding another questionnaire produced 79% sensitivity and 69% specificity. These figures show why an algorithm should not replace a clinical interview and examination.
A separate secondary analysis used 20 weeks of data from 182 participants in a migraine diet trial. Across four 28-day periods, participants recorded an average of 13.7 headache days in the daily diary and recalled 11.1 days on monthly questionnaires. Recall was closer for headaches lasting at least eight hours. The study supports prospective recording for frequency estimates, but it does not show that keeping a diary reduces headaches.
A simple entry
Start with the information that can change a clinical decision:
- start and end time, or whether it was a headache day;
- pain intensity and effect on normal activity;
- associated symptoms such as nausea, aura, light sensitivity or dizziness;
- acute medication, dose and time taken;
- whether the medicine appeared to help;
- menstruation or another specific context your clinician asked you to track.
Use the same definitions each day. If you change what counts as a headache day halfway through, note the change. Recording headache-free days helps distinguish missing entries from days without symptoms.
Avoid logging every possible food, emotion, weather value and activity by default. A long checklist can become difficult to maintain and creates many accidental correlations. Add one focused question when you have a reason to test it, and include days when the suspected factor occurs without headache. Multi-trigger migraine tracking discusses this problem in more detail.
Paper or digital
Paper, a spreadsheet and an app can all create a useful diary. The best format is one you can complete consistently and bring to an appointment. Digital tools may timestamp entries, calculate totals and export a report, but those features do not guarantee accurate entries or a correct diagnosis.
Before using an app, check account requirements, storage, export and deletion. How to check privacy in a health app provides a practical checklist. HeadYogi's features page describes its current export and storage options; those product claims are separate from the medical evidence above.
Reviewing the record
Summarize headache days, migraine days if your clinician uses that category, acute-medication days and the effect on functioning. Bring the underlying diary as well as the totals. Preparing a headache report for your doctor can help structure the appointment.
Do not start, stop or increase medication because an app labels a pattern. Seek medical assessment for a sudden severe headache, new neurological symptoms or a marked change from your usual pattern.
FAQ
Can a headache diary diagnose migraine?
No. It records information that may support diagnosis. A clinician still needs to assess symptoms, history and relevant examination findings.
Does keeping a diary reduce headache days?
The studies cited here compare prospective entries with recalled estimates. They do not establish the diary itself as a headache treatment.
Do I need to record every possible trigger?
No. Start with headache days, duration, severity, associated symptoms and medication. Add focused context when it serves a clear question.
Related reading
- How to prepare a headache report for your doctor
- Headache diary apps explained
- Sleep regularity and migraine
- Migraine and multiple possible triggers
- How to check privacy in a health app
Sources (Open Access and Official Guidance)
- Headaches in over 12s: diagnosis and management, recommendations (NICE)
- E-diary use in clinical headache practice: A prospective observational study (Cephalalgia, 2021; PMCID: PMC8504420)
- Comparing prospective headache diary and retrospective four-week headache questionnaire over 20 weeks: Secondary data analysis from a randomized controlled trial (Cephalalgia, 2020; PMCID: PMC9060397)
HeadYogi can record headache days, symptoms and medication and export a report. Learn how it works or download the app.