How to keep
a symptom diary.

What a symptom diary is for

Doctors ask the same three things about a symptom: when it started, how often it comes, and whether anything sets it off. A diary answers all three with dates. It is most useful for anything that comes and goes: migraines, flare-ups of a skin or gut condition, palpitations, poor sleep, a child's cough at night. It is also how you notice that a new medicine, a food or a bad week lines up with the episodes.

The six things to write each time

• Date and time. Including the time matters for anything that follows a daily pattern: headaches after lunch, wheeze at 3 am.
• What it was. Use the same word each time. "Headache" and "migraine" are different entries; pick one and keep to it.
• How bad. A number on a scale you keep to. One to ten is enough. The absolute value matters less than the change over time.
• How long. Minutes, hours or days.
• What was going on. Sleep, food, stress, a missed dose, the weather, a period. Short words, not a diagnosis.
• What you did about it, and whether it helped: a tablet, rest, water, nothing.

Keep it short and keep it going

The diary that gets kept is the one that takes thirty seconds. Resist the urge to write paragraphs; a long entry on a bad day followed by a month of nothing is less useful than thirty short ones. If a day had no symptoms, you do not need to write "nothing". The gaps are information too.

Photos help for anything visible: a rash, a swollen joint, a mole. Take the photo in daylight, with something for scale, and file it with the entry so the date travels with it.

Reading it back

Before an appointment, read the last few weeks and count. How many episodes, how severe on average, the worst one, and anything that lines up. That count is what you tell the doctor; the diary itself is there if a detail is asked for. Do not diagnose from the pattern yourself. The diary's job is to make the conversation accurate, not to replace it.

Where Biojrnl fits

In Biojrnl you pick a body area, then the symptom under it: Gut Health then Bowel Movement, Head & Dizziness then Migraines, Respiratory then Asthma Flare, and so on across 17 areas, with a severity rating and a note. Every entry is dated and filed by month, and you can follow an entry up later as a thread, so one problem reads as a story rather than scattered notes. Overview counts your most-logged areas from your own entries; it does not score or interpret them. The record exports on every plan, and Visit Prep (Pro and above) puts the recent entries on one page for the appointment. It works offline and the journal is encrypted on your phone. The free plan holds 20 entries with no time limit; Pro is unlimited at £4.99 a month. See the journal screens and how to keep a health journal for your doctor.

This guide is about keeping your own notes. It is not medical advice. If you are unwell, speak to a qualified clinician; in an emergency, contact the emergency services.