Chronic pain

Chronic pain
Other namesChronic pain syndrome
SpecialtySpecialist in pain, neurology and psychology
SymptomsPain lasts longer than the expected period of recovery.
Usual onsetAll age groups
DurationAt least 3 months
CausesHigh blood sugar, cancer, genetic disorder in neural differentiation, tissue damage, neurological disorders, viral diseases
Risk factorsDiabetes, cancer, heart disease
Diagnostic methodBased on medical history, clinical examination, questionnaire and neuroimaging
Differential diagnosisGastric ulcer, bone fracture, hernia, neoplasia of the spinal cord
MedicationNon-opioid: ibuprofen, acetaminophen, naproxen, NSAIDs, olanzapine
Opioid: morphine, codeine, buprenorphine
Frequency8% to 55.2% in different countries

Chronic pain is pain that persists or recurs for longer than 3 months. It is also known as gradual burning pain, electrical pain, throbbing pain, and nauseating pain. This type of pain is in contrast to acute pain, which is pain associated with a cause that can be relieved by treating the cause, and decreases or stops when the cause improves. Chronic pain can last for years. Persistent pain often serves no apparent useful purpose.

The most common types of chronic pain are back pain, severe headache, migraine, and facial pain.

Chronic pain can cause very severe psychological and physical effects that sometimes continue until the end of life. Analysis of the grey matter (damage to brain neurons), insomnia and sleep deprivation, metabolic problems, chronic stress, obesity, and heart attack are examples of physical disorders; and depression, and neurocognitive disorders are examples of mental disorders.

A wide range of treatments are performed for this disease; drug therapy including opioid and non-opioid drugs, cognitive behavioral therapy and physical therapy are the most significant of them. Medications such as aspirin and ibuprofen are used for milder pain and morphine and codeine for severe pain. Other treatment methods, such as behavioral therapy and physiotherapy, are often used as a supplement along with drugs due to their low effectiveness. There is currently no definitive cure for chronic pain, and research continues into a wide variety of new management and therapeutic interventions, such as nerve block and radiation therapy.

An average of 8% to 11.2% of people in different countries have severe chronic pain, with higher incidence in industrialized countries. Epidemiological studies show prevalence in countries varying from 8% to 55.2% (for example 30-40% in the US and 10-20% in Iran and Canada). Chronic pain is a disease that affects more people than diabetes, cancer, and heart disease.

According to the estimates of the American Medical Association, the costs related to chronic pain in the US are about US$560-635b.