The first difference between acute vs chronic pain is time. The International Association for the Study of Pain (IASP) and the World Health Organization, in its ICD-11 classification, call pain chronic when it lasts or keeps coming back for longer than three months. Some older sources use six months.
Three months is a marker set by the classification. The weeks before it matter more to you: during that time you collect the information your doctor will later use to judge whether the pain is fading, holding steady or returning in flare-ups.
Acute pain: a warning signal with a cause
Acute pain starts with a cause you can usually name, such as a sprain, dental work, an infection or surgery. It makes you protect the injured area, and it eases as the tissue heals. After a pulled muscle you expect days to a few weeks. After surgery it depends on the procedure and often takes longer.
In this phase, note when the pain starts and what makes it worse, for example standing up or bending down. If the pain lasts well beyond the expected healing time, book an appointment. You do not need to wait for the three-month mark.
Chronic pain: longer than three months
ICD-11 sorts chronic pain into two groups. Chronic primary pain is treated as a condition in its own right, fibromyalgia being one example. Chronic secondary pain stems from another disease or injury, for instance after surgery, with cancer or after nerve damage.
Chronic pain includes pain that comes and goes. Migraine attacks over years, or back pain that returns every few weeks, both fit the definition. With long-lasting pain, your nervous system can also become more sensitive to signals, and your sleep, mood and work suffer along with it.
| Acute | Chronic | |
|---|---|---|
| Duration | until healing, often days to weeks | more than three months, constant or recurring |
| Link to a cause | clear | sometimes unclear, or the injury has healed |
| Course | goes down | steady, in flare-ups or fluctuating |
| Most useful note | does the weekly value drop? | effect on daily life, patterns, response to treatment |
Record the first three months
Start a diary while the pain is new. Later, your doctor can only work with what you wrote down during this phase. These points are enough:
- [ ] Start: date and cause, such as "fell on the stairs" or "no clear reason"
- [ ] One value per day on a fixed scale, including 0 on pain-free days. For comparable numbers, see the 0 to 10 pain scale
- [ ] Location: does the pain stay in one spot, move around, or spread?
- [ ] Effect on daily life: sleep, work, walking distance, stairs
- [ ] Treatments with a start date: medication, physical therapy, surgery
- [ ] Medications with time taken and effect
Say you strained your back moving house in June. Your weekly average is 6 in week one, 3 in week four, and 1 in week eight with lots of zeros. That is a fading course. If your average in week eight is still 5, you see it in your own numbers and raise it before the three months are up.
The full method is in how to keep a pain diary.
Reading the course
After a few weeks your entries show one of three patterns:
- Fading: weekly averages drop and pain-free days increase.
- Steady: values hover at one level, week after week.
- Recurring: good weeks alternate with flare-ups. Note what happened in the days before a flare, such as unusual strain or poor sleep.
Compare weeks and months with each other, since single days tell you little. Also count how many days per month were affected. Your doctor can do more with that number than with your highest score.
Acute and chronic pain in PainTrack
Set up the pain as a pain definition and log one value a day, with a 0 on good days. Mark the start of the pain, an operation or the start of a therapy as an event. Events are free.
- Free: the History chart on the Analysis page over 7 and 30 days, the Body map as a heatmap over 7 and 30 days, events, the Weekly trend and reminders. The Diary shows the last three months, and older entries stay stored.
- Pro: History chart and Body map over 90 days and "All", which covers the full three-month span. Monthly reports add documented and pain-free days, average, minimum, maximum and the change from the previous month, plus the PDF doctor's report.
The Body map shows you whether pain spreads from one spot to others. With the monthly reports you can lay three months side by side.
Bring three months of data to your appointment
For each month, bring the number of affected days, the average and the effect on daily life, plus the date of each treatment. Preparing for a pain appointment covers the rest. Write down beforehand what you hope to get from the visit, for example a look at the cause or a referral. With that question on paper you can steer the conversation when time is short.
Start with your GP or primary care doctor. For pain that has lasted months, a pain clinic or pain management service may be the next step. More on that in when to see a pain specialist.
Call 911 in the US or 999 in the UK, or get help right away, for sudden severe pain, chest pain with shortness of breath, pain with a high fever, weakness or numbness, and pain after an accident.
Frequently asked questions
When is pain considered chronic? Under the IASP and ICD-11 definition, once it has lasted or kept coming back for more than three months. Your doctor decides how it applies to you.
Can acute pain turn into chronic pain? Yes, acute pain can persist beyond the time the tissue needs to heal. If it lasts longer than expected, raise it early and bring your records.
Is chronic pain there all the time? No. Pain that returns in attacks or flare-ups over months also counts as chronic, migraine being one example.
Should I wait three months before seeing a doctor? No. The three months come from a definition and set no waiting period. See a doctor sooner for severe, unusual or persistent pain.
PainTrack is not a medical device and does not replace medical diagnosis or treatment. The app is intended for personal documentation and self-observation.