Guides

Practical guides, grounded in the evidence.

The questions clinicians and researchers get asked most often — answered honestly, citing the papers, and clear about what Hermly does and doesn't do.

How these guides are organised

Most migraine "guide" content on the web falls into one of two failure modes: shallow listicles that don't cite their sources, or clinical references too technical for a non-specialist audience. The guides here aim for the middle — plain-English walk-throughs of specific questions, with the underlying evidence linked rather than glossed over.

They're grouped by intent: the diagnosis-and- basics section helps you figure out what you're dealing with; the tracking section covers how to capture useful data; the treatment-timing section addresses the decisions that come up with a clinician. Every guide includes citations to the peer-reviewed source where the claims come from.

Diagnosis & basics

What is migraine, what's not, what do my symptoms mean.

Migraine vs headache: the actual difference

Migraine is a specific neurological disorder, not just a 'bad headache'. The ICHD-3 criteria draw a clear line — here's where it lands.

Migraine without aura — the most common subtype

Migraine without aura is roughly 70% of all migraine. The ICHD-3 criteria require 5+ attacks lasting 4–72 hours with specific pain and accompanying symptoms.

How long do migraines last? The ICHD-3 window

ICHD-3 defines an untreated migraine attack as 4–72 hours. Some are shorter, some longer — here's what the duration variation actually means.

Migraine warning signs — the prodrome you can spot

The prodromal phase brings recognisable warning signs hours to days before the headache. Here's what to watch for and what published research shows.

Chronic vs episodic migraine — the 15-day threshold

Episodic migraine is fewer than 15 headache days/month. Chronic migraine is 15+. The threshold matters clinically — and for forecast model behaviour.

Tracking & technology

How to log, what to log, what Hermly does with it.

How to track migraine triggers — a method that works

The classic 'trigger diary' approach has well-known limits. Here's a research-aware protocol — what to log, what to ignore, and how to read your own data.

Can Apple Watch detect a migraine?

Apple Watch can't detect migraine on its own — but HRV, sleep, and wrist-temp signals improve prediction. Research-backed, with how Hermly uses them.

How to log a migraine in Apple Health

Apple Health has a Headache category since iOS 13. Here's how to log attacks manually, why Hermly writes them automatically, and how to keep both in sync.

Treatment timing & care decisions

When to take what, when to escalate, who to see.

When to take migraine medication — the timing question

Acute migraine treatments work better the earlier they're taken — but 'earlier' has limits. Here's what published trials show, without telling you what to do.

How to talk to your doctor about migraines

A 15-minute visit can change your care if you bring structured data. Here's what clinicians actually want to see, and how to use Hermly's report.

Migraine during pregnancy — what changes

Migraine frequency usually falls during pregnancy, especially second and third trimesters. Treatment options narrow — a conversation for your doctor.

Pediatric migraine — what's different in children

Migraine in children differs from adults — shorter attacks, more abdominal symptoms, often genetic. Pediatric care belongs with a pediatrician.

What's not here

Several topics deliberately don't have guides — they're questions Hermly thinks belong with a clinician, not an app:

Common questions about the guides

How often are these updated?

Last reviewed May 2026. We update guides when new peer-reviewed evidence meaningfully changes the picture (a major trial, a regulatory change, a new well-validated medication class), and at minimum once a year for currency.

Why don't these recommend specific medications?

Hermly is a wellness app, not a clinician. Recommendations on specific medications, doses, or combinations are inappropriate for an app to make — they depend on your full medical context. Guides describe the medication landscape; your prescriber chooses the regimen.

Can I link to a guide for someone else?

Yes — guides are public, no login required. Each guide has its own URL and can be shared via any channel. Several guides are written specifically for sharing with a partner, parent, or doctor.

Found an error in a guide?

Email [email protected] with the page URL and the correction. We take editorial accuracy seriously — citations get checked, and an authoritative source for the correction speeds the turnaround.

Early access

Quiet migraine intelligence, kept private.