How to keep a symptom diary for your doctor comes down to seven things recorded the same way every day: the date and time, the symptom itself, how long it lasted, how bad it was, what came before it, what you took, and what it stopped you doing. Record the days nothing happens too.
The seven things, in one block
If you take one thing from this page on how to keep a symptom diary for your doctor, take this list and start tonight.
- Date and time of every episode, written at the time it happens.
- The symptom in your own plain words, using the same words each time.
- How long it lasted, plus every day it did not happen.
- Severity on one scale, used for every single entry.
- What you were doing, eating and feeling in the hours before.
- Anything you took, and what changed afterwards.
- The specific thing the symptom stopped you doing.
1. Date and time of every episode
Write the date and the clock time at the start of every entry, before you write anything else.
Timing is one of the first things a clinician reaches for. The US National Institute on Aging lists the questions a doctor usually asks about any symptom, and the list opens with when it started and what time of day it happens. A symptom at 3am is a different clue from the same symptom after lunch, and only a timestamp separates them.
Write it in the moment rather than at the end of the week. Research on symptom recall is mixed, with studies finding both overestimation and underestimation of past pain, but one consistent thread is that your current state colours what you recall about earlier days. Shortening the gap between the event and the record is the simplest way around that. A quick note on your phone, copied into the diary later, is enough.
Why it matters: timestamps do work your memory cannot, and cost you five seconds.
2. The symptom in your own plain words
Describe what you actually felt in ordinary language, and use the same words every time you feel it.
You do not need medical vocabulary. The National Institute on Aging puts it plainly: be clear and concise about your symptoms, because your description points the doctor in the right direction while exams and tests fill in the rest. Doctors are trained to work with everyday descriptions.
Consistency matters far more than the words you pick. If you write burning on Monday, stinging on Thursday and sore on Sunday for one sensation, the pattern dissolves into noise. Choose one word and stay with it. Add where you felt it and mark if it moved, because location and movement are separate information.
Keep entries short. Two lines written for six weeks beat a paragraph abandoned after four days.
Why it matters: one word used consistently turns scattered bad days into a readable pattern.
3. How long it lasted, and the days it did not happen
Record the duration of each episode, and mark the symptom-free days as well.
NICE guideline CG150 on headaches in over 12s asks people using a headache diary to record frequency, duration and severity across a minimum of eight weeks. Frequency is the part most people get wrong. It is a count across a window, so the window has to be complete. Eight entries mean something very different across eight weeks than across eight days.
That is why blank days are a problem. A gap is ambiguous: it could mean no symptoms or it could mean you forgot. Put a short entry on clear days too, even one word. The quiet stretches are data, and often the part that shows a trigger or a treatment starting to work.
Why it matters: without the clear days on the page, nobody can tell how often the bad ones come.
4. Severity on one scale you keep using
Pick a single 0 to 10 scale and apply it to every entry for the whole period.
Severity sits alongside frequency and duration in the NICE CG150 diary fields. The scale you choose matters far less than using the same one throughout. A 6 today only means something if last week’s 4 was measured the same way.
This is where a diary earns its keep. Evidence on recalled pain is contested and studies disagree on the direction of the error, but a documented effect is that the worst moment and the most recent moment pull your later estimate around. A 1993 study in the journal Pain found patients assessed straight after physiotherapy recalled the past week as milder than their own electronic diary showed, while a comparison group overestimated theirs.
Rate it when it happens, not on the drive to the clinic.
Why it matters: one consistent scale gives your clinician a trend line, not unrelated guesses.
5. What was happening in the hours before
Note what you were doing, eating, drinking and feeling in the few hours before the symptom started.
NICE CG150 asks headache diary users to log possible precipitants alongside the symptom. The principle carries across other diaries. NICE guidance on urinary incontinence in women asks for a bladder diary of at least three days, and specifies it should cover variations in usual activities, including working days and leisure days.
That instruction is worth borrowing. A diary covering only weekdays hides half your life. If your symptom tracks with commuting, with sleeping in, or with a particular meal, a Monday to Friday record will never show it. Cover a full normal week where you can.
Write what was true, not what you suspect. Guessing at a cause steers what you notice next.
Why it matters: your clinician needs what moves the symptom, and only you were there.
6. Anything you took, and what changed after
List everything you took for the symptom and what happened next, including the times it made no difference.
NICE CG150 asks for all prescribed and over-the-counter medications taken to relieve headaches. The National Institute on Aging goes wider, asking patients to tell the doctor about every medicine they take, plus vitamins, herbal remedies and supplements, because interactions matter and are easy to leave out.
Record the response honestly. A painkiller that did nothing is as informative as one that worked, and a symptom easing on its own after an hour tells a different story from one that settles only after medication. Note the time you took it and the time it changed.
One boundary. A diary is a record, not a reason to start, stop or adjust a prescription. Any change to a prescribed medicine is a conversation with the prescriber.
Why it matters: what did not work narrows the picture as fast as what did.
7. The specific thing it stopped you doing
Write down the concrete activity you had to skip, shorten or leave early.
The National Institute on Aging lists this among the standard questions: does the symptom keep you from going out or doing your usual activities. It is the field people skip most, and the one that travels best into a consultation.
Function is specific in a way adjectives are not. Left work at 2pm and could not drive is concrete. Felt awful is not. Two people can both write severe and mean different things, but nobody misreads missed the school run twice this week.
It also shows improvement that pain scores miss. If the number stays at 6 but you stopped cancelling things, something has changed and it is worth saying out loud.
Why it matters: impact on daily life is often what decides the next step in your care.
How long should you keep it?
Ask the clinician who requested it. Where guidance sets a minimum, it varies by what is being investigated.
There is no single answer to how to keep a symptom diary for your doctor over time, because the useful length depends on the question being asked. A headache pattern needs weeks. A bladder pattern needs days. Both figures below come from published NICE guidance.

Minimum diary periods set out in published guidance:
| What the diary is for | Minimum period | Named source |
| Helping diagnose a headache type | 8 weeks | NICE CG150, Headaches in over 12s |
| Migraine that tracks with periods | At least 2 menstrual cycles | NICE CG150, Headaches in over 12s |
| Bladder symptoms and leakage | 3 days, covering working and leisure days | NICE, Urinary incontinence and pelvic organ prolapse in women |
| A new symptom before a first appointment | No set minimum. Whatever you can complete before the visit | National Institute on Aging, What Do I Need to Tell the Doctor |
If nobody set a period, two to four weeks suits most new symptoms and is short enough to finish. Agree an end date before you start.
When tracking stops helping
A diary with a start date and an end date is a tool. Open-ended monitoring of your own body is something else, and it can make things worse.
Most guides leave this out. The cognitive-behavioural model of health anxiety, developed by Salkovskis and Warwick, describes how repeated body checking and reassurance seeking maintain health anxiety rather than settle it, because close attention to normal bodily variation makes that variation more noticeable and more alarming. A 2018 systematic review in the Journal of Psychosomatic Research examined 62 studies against that model and found support for those mechanisms.
So set an end date. If filling in the diary is raising your anxiety rather than organising it, stop and say so at the appointment. That is useful clinical information, not a failure.
A diary never overrides urgency. If a symptom is severe, sudden, or worsening quickly, do not wait to finish it. Contact urgent care or your emergency service straight away: NHS 111 or 999 in the UK, 112 in India, 911 in the US.
Bringing the diary into the appointment
Do not hand over the whole diary. Bring one page that summarises it, plus the three things you most want answered.
Appointments are short, and in much of the world very short. A 2017 systematic review in BMJ Open by Irving and colleagues pooled 179 studies covering more than 28.5 million consultations across 67 countries. Average primary care consultation length ranged from 48 seconds in Bangladesh to 22.5 minutes in Sweden, and the authors concluded that a large share of the global population gets only a few minutes with a physician.

Forty pages will not be read in that window. One page will. Summarise it: how many episodes across how many weeks, typical duration, usual severity, what seemed to precede it, what you took, and what you had to stop doing.
The National Institute on Aging suggests picking three or four concerns you most want covered and raising them at the start of the appointment rather than the end. Lead with your summary rather than the raw pages, and offer the full diary if it is wanted.
Start your one-page summary tonight and take it to your next appointment.
Frequently asked questions
How do you keep a symptom diary for your doctor?
Record seven things for every episode: the date and time, the symptom in plain words, how long it lasted, its severity on one fixed scale, what happened in the hours before, anything you took, and what it stopped you doing. Note symptom-free days too.
How long should I keep a symptom diary before my appointment?
It depends on the question. NICE asks for a minimum of eight weeks for a headache diary and a minimum of three days for a bladder diary. For a new symptom with no set period, two to four weeks is a practical target you are likely to finish.
Should I use an app or paper?
Use the one you will actually open. Paper works if it lives somewhere you pass daily. An app works if the notification reaches you. What matters is recording at the time rather than reconstructing later, and keeping the same fields in the same order.
What should I write on a day with no symptoms?
Write that there were none. A blank line is ambiguous, because it could mean a clear day or a day you forgot. One word is enough. Clear days are what make frequency meaningful, and they often reveal the pattern more clearly than the bad days.
Will my doctor actually read my symptom diary?
They are far more likely to read a one-page summary than a full notebook. Consultations are short and in many countries last only a few minutes. Bring the summary, mention that the full diary exists, and offer it if your clinician wants the detail.
Can a symptom diary diagnose my condition?
No. A diary is a record of what you experienced, not a diagnosis. NICE describes diaries as an aid to diagnosis, used alongside examination and tests. Only a qualified clinician who knows your history can interpret what your entries mean for you.
A symptom diary is a small habit that changes what a short appointment achieves. It replaces what you half remember with what you recorded.
Pick a start date, agree an end date, and take one summary page to your next appointment.
This article is for general education only. It does not replace a consultation, diagnosis or treatment from a qualified healthcare professional. If you are worried about a symptom, contact your doctor or local health service.
Sources
- National Institute for Health and Care Excellence. Headaches in over 12s: diagnosis and management (CG150). Recommendation 1.1.4 on headache diaries.
- National Institute for Health and Care Excellence. Urinary incontinence and pelvic organ prolapse in women: management (NG123) and Quality Standard QS77. Bladder diaries, minimum three days.
- National Institute on Aging, US National Institutes of Health. What Do I Need to Tell the Doctor. Updated 2025.
- National Institute on Aging, US National Institutes of Health. Five Ways to Get the Most Out of Your Doctor’s Visit. Updated 2026.
- Irving G, Neves AL, Dambha-Miller H, et al. International variations in primary care physician consultation time: a systematic review of 67 countries. BMJ Open 2017, 7(10): e017902.
- Feine JS, Lavigne GJ, Dao TTT, et al. Memories of chronic pain and perceptions of relief. Effects of present pain level on recall of chronic pain and medication use. Pain 1993. Referenced for diary versus recall discrepancy.
- Kohler S, Silvestrini M, et al. How do illness-anxious individuals process health-threatening information? A systematic review of evidence for the cognitive-behavioral model. Journal of Psychosomatic Research, 2018. 62 studies reviewed.
- Salkovskis PM, Warwick HMC. Cognitive-behavioural model of health anxiety, 1986, and subsequent developments.
