Health Topic

Pain

Pain is a feeling triggered in the nervous system. You may feel it as a prick, tingle, sting, burn, or ache. Read about the causes and what can help.

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Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.

About Pain

Pain is a signal in your nervous system that something may be wrong. It is an unpleasant feeling, such as a prick, tingle, sting, burn, or ache. Each person feels pain differently, even if the reason for the pain is the same. Pain may be sharp or dull. It may be mild or severe. Pain may come and go, or it may be constant. You may feel pain in one area of your body, such as your back, abdomen, chest, or pelvis, or you may feel it all over.

Pain can help alert you that there is a problem. If you never felt pain, you might seriously hurt yourself without knowing it, or you might not realize you have a medical problem that needs treatment. Finding out what's causing your pain will help your health care provider determine the best way to manage or treat it.

Patterns and types of pain are named based on how long and how often you have pain. These include:

  • Acute pain usually happens suddenly because of a disease, injury, or inflammation (irritation, redness, and/or swelling). This type of pain is often sharp and acts as a warning that something is wrong. It usually goes away when the cause is treated or healed, though sometimes it can turn into chronic pain. Some examples of causes of acute pain include broken bones or dental issues.
  • Chronic pain lasts for longer than three months or the time in which you should have healed. It can affect all aspects of daily life, including your mood and relationships. Some conditions that might cause chronic pain include arthritis or back problems.
  • Episodic pain can happen from time to time and may occur with long-term medical conditions. Some conditions that might cause episodic pain include sickle cell disease or chronic migraines.

Pain may also be categorized by what is likely to be the cause of the pain. Pain may be described as nociceptive (caused by tissue damage or inflammation), neuropathic (caused by nerve damage), or nociplastic (caused by changes in how your nervous system processes pain).

Understanding what causes pain and why people feel it differently may be difficult. Often, it's easier to find the cause of acute pain due to an injury than the cause of chronic pain, or you may have an ongoing cause of pain, such as cancer.

In some cases, there is no clear cause. Environmental factors and psychological factors such as stress and beliefs about pain may affect the way you feel pain and respond to treatment.

You are the only one who knows how your pain feels. Your provider can best measure your pain by how you report it. They may ask you:

  • Where is the pain in your body?
  • How long have you had the pain?
  • How does the pain feel, such as stinging, burning, or sharp?
  • How often do you have pain?
  • When do you feel pain, such as in the morning, evening, or all the time?
  • What relieves the pain?
  • How does pain affect your daily life?
  • Is the pain mild, moderate, or severe?
  • To rate the pain on a scale.

If the cause of your pain is unknown, your provider may also do a physical exam and order blood tests or other medical tests to help find the cause.

Pain is not always curable, but there are many ways to manage and treat it. Treatment depends on the cause and type of pain. Treatments may include medicines, such as pain relievers. There are also non-drug treatments, such as acupuncture, physical therapy, and sometimes surgery.

Depending on the cause of your pain and your symptoms, your provider may recommend lifestyle changes. These may include suggestions for:

  • Eating a healthy diet
  • Adding exercise
  • Losing weight
  • Managing stress
  • Improving mental health

It sits within Brain and Nerves and Symptoms.

The lead U.S. institute for this subject is the National Institute of Neurological Disorders and Stroke.

When to speak to someone. Reading about a topic cannot tell you whether it applies to you. Speak to a doctor or pharmacist if symptoms are severe, sudden, getting worse, or simply not going away — and seek emergency care immediately for chest pain, breathing difficulty, sudden weakness or confusion, or a serious allergic reaction.

Research on Pain

37,009 studies areregistered for this condition on ClinicalTrials.gov, the U.S. National Library of Medicine's public registry. A selection is below — the links go straight to the registry entry, not to a summary of ours.

What a registered study does and does not mean. Registration means a study exists and has been declared publicly. It says nothing about whether the treatment being tested works, is safe, or is available to you. Many studies find no benefit — that is what research is for. Never seek out an experimental treatment on the strength of a registry entry alone.

Research currently under way

Research already completed

Study data from ClinicalTrials.gov, a service of the U.S. National Library of Medicine. Retrieved 2026-07-30. Registry entries are supplied by study sponsors and investigators; ClinicalTrials.gov does not verify their scientific validity. PocketsInfo is not affiliated with, and not endorsed by, the NLM or the NIH.

Where to read more

Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.

Start Here

Treatments and Therapies

Living With

  • Pain LogAmerican Chronic Pain Association

Related Issues

Genetics

Clinical Trials

Medical subject headings

Clinicians and researchers index this subject under Pain, Pain Perception, Pain Management. These are the terms to use when searching medical literature.

This page is built from the MedlinePlus health topic record for Pain, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.