Pain: Types, Acute vs Chronic, and What Your Pain Is Telling You

What pain is

The International Association for the Study of Pain defines pain as an unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage. In plain terms: pain is real, it is felt in the body, and the brain shapes how strongly you feel it based on context, mood, sleep and past experience.

There are three broad mechanisms:

Words people use to describe pain, and what they suggest

Crushing pain in the chest is a classic description of a heart attack. Call 911 or your local emergency number rather than driving yourself.

Pain by location: where to start

Where pain sits narrows the list of causes more than any other single clue. Use this table as a pointer, then go to the page for that area.

Pain between the lower ribs and the hip, on the left or right, has its own set of causes, from a running stitch to a kidney stone. Our guide to side pain on the left and right sorts them by exact location and explains when to worry.

How to describe your pain to a doctor

A clear description often points to the cause before any test is done. Before your appointment, note:

• Where it is, and whether it stays in one spot or moves. Point with one finger if you can.
• When it started and what you were doing: lifting, eating, lying down, exercising.
• What it feels like, using the words in the table above. "Sharp" and "dull" mean different things to doctors (see sharp pain).
• The pattern: constant, in waves, only with movement, worse at night or in the morning.
• What helps and what makes it worse: rest, food, a position, a painkiller.
• How bad it is on a scale of 0 (no pain) to 10 (worst imaginable), and how it affects sleep, work and walking.
• Other symptoms: fever, numbness, weakness, nausea, weight loss, urine or bowel changes.

A pain diary kept for 1 to 2 weeks is especially useful for headaches, belly pain and chronic pain.

Acute vs chronic pain

Acute pain follows an injury, surgery or illness and fades as tissues heal, usually within days to weeks.

Chronic pain lasts more than 3 months. It affects about 1 in 5 adults in the US. It can continue after tissues have healed because the nervous system has become sensitized. Examples include chronic back pain, arthritis, migraine, fibromyalgia and neuropathic pain. Chronic pain is linked with poor sleep, low mood and anxiety, which in turn amplify pain. Treatment works best when it addresses all of these. See chronic pain.

How doctors assess pain

Doctors often use the mnemonic SOCRATES:

• Site: where exactly?
• Onset: sudden or gradual? What were you doing?
• Character: sharp, dull, burning, crushing?
• Radiation: does it spread anywhere?
• Associated symptoms: fever, nausea, numbness, urine or bowel changes?
• Timing: constant or in waves? How long?
• Exacerbating and relieving factors: what makes it better or worse?
• Severity: a score from 0 (none) to 10 (worst imaginable)

Tests depend on the likely cause: urine tests for kidney problems, blood tests for infection or inflammation, ECG for chest pain, and imaging such as ultrasound, X-ray, CT or MRI.

Treatment and home care

For short-term pain

• Rest the painful area briefly, then gradually return to normal movement. Long bed rest slows recovery for most muscle and back pain.
• Ice for 15 to 20 minutes in the first 48 hours after an injury. Heat for muscle stiffness and cramps.
• Acetaminophen (paracetamol): for mild to moderate pain. Do not exceed the label dose, and count it in combination products, because overdose damages the liver.
• NSAIDs such as ibuprofen or naproxen: for pain with inflammation. Follow the label dose. Avoid them if you have stomach ulcers, kidney disease, heart failure or take blood thinners.
• Topical NSAID gels: useful for joint and muscle pain with fewer side effects.
• Do not give aspirin to children or teenagers.

For chronic pain

• regular graded exercise and physical therapy
• cognitive behavioral therapy and pain education
• sleep improvement
• medicines aimed at the type of pain, such as certain antidepressants or anticonvulsants for nerve pain
• opioids are rarely the right long-term answer and are used cautiously, following CDC guidance

Do not take a painkiller to mask severe or unexplained pain without finding the cause, especially abdominal or chest pain.

Frequently asked questions

What are the main types of pain?

Doctors describe three mechanisms. Nociceptive pain comes from injured or inflamed tissue, such as a sprain or appendicitis. Neuropathic pain comes from damaged nerves and tends to burn, shoot or tingle. Nociplastic pain arises from an oversensitive nervous system, as in fibromyalgia. Pain is also classed by time: acute if recent, chronic if it lasts more than 3 months.

What does crushing pain mean?

Crushing, squeezing or heavy pain in the chest is a classic warning sign of a heart attack or angina, especially if it spreads to the arm, neck, jaw or back or comes with sweating or breathlessness. Call 911 or your local emergency number immediately.

When should I worry about pain?

Get emergency help for crushing chest pain, a sudden "worst ever" headache, tearing chest or back pain, severe belly pain with a rigid abdomen, or pain with weakness, numbness or confusion. See a doctor soon for pain with fever, pain that wakes you at night, pain with weight loss, or any pain lasting more than 2 weeks without improvement.

What is the difference between acute and chronic pain?

Acute pain is recent, has a clear cause such as an injury or illness, and fades as you heal. Chronic pain lasts more than 3 months, often after tissues have healed, because the nervous system remains sensitized. It needs a broader treatment approach.

What is neuropathic pain?

Neuropathic pain comes from damaged or irritated nerves rather than injured tissue. It typically burns, shoots, stabs or tingles, and may come with numbness. Diabetes, shingles, sciatica and chemotherapy are common causes. Standard painkillers often help little, but specific nerve pain medicines can.