Acute, Chronic, and Subacute Pain Differences

Acute, chronic, and subacute are three different ways to describe pain. Acute pain is pain that comes on quickly, usually as a result of a traumatic accident or illness. Chronic pain is pain that develops more slowly and is persistent or long-lasting. Subacute pain is somewhere in between the two. 

Different types of pain have different treatment strategies. For example, healthcare providers treat acute pain by treating the underlying cause. Chronic pain may require different strategies like physical therapy, injection therapies like steroids, and/or prescription pain medications.

This article goes over acute, chronic, and subacute pain and how each type is managed and treated.

Acute Pain

Acute pain refers to any specific, sharp pain that is of rapid onset or pain that results from a specific traumatic incident such as an injury to a specific part of the body, or an illness. Acute pain tends to be very isolated.

Such pain comes on quickly but often has a limited overall duration. An acute injury is usually the result of a specific impact or traumatic event that occurs in one specific area of the body, such as a muscle, bone, or joint. Patients often think the word "acute" means severe, but healthcare professionals do not use the term in that way.

Chronic Pain

The opposite of acute pain is chronic pain. Chronic pain refers to any sort of physical injury, illness, or disease that develops slowly. Rather than being short-lived and finite, chronic pain is persistent and long-lasting, or constantly recurring over time.

Chronic pain is usually defined as pain that lasts for more than three months. The term may also be used to describe pain that interferes with daily activities for 12 weeks or longer. Chronic pain can last for months or years. Some people have chronic pain that needs to be managed for the rest of their lives. 

Chronic pain can have many causes, including a past injury or illness that you have otherwise recovered from. It can also be caused by a condition like osteoarthritis, diabetic neuropathy, or fibromyalgia. People with advanced cancers may also experience chronic pain.

Subacute Pain

Subacute pain has a less specific definition than acute or chronic pain and there may be some overlap between what certain healthcare providers consider to be acute, subacute, or chronic pain. Generally speaking, however, subacute pain is pain that lasts longer than acute pain but does not last as long as chronic pain. Usually, this means more than four weeks but less than three months. 

Subacute pain may be persistent or intermittent or it may only be present when the person is moving a certain part of their body or sitting, standing, or lying down in a certain way. It may feel dull or sharp. Subacute pain is not necessarily worse than acute pain, but it does persist for a longer period of time.

Subacute pain may be caused by inflammation, swelling, scar tissue, or tissue that is still healing. Both acute and subacute pain may evolve into chronic pain, especially if they are insufficiently treated.

How Is Acute Pain Treated?

Acute pain from an injury issue typically requires immediate medical attention, including first aid treatment to treat the underlying cause of the pain. Your healthcare provider may also recommend over-the-counter pain medications and at-home strategies for managing and relieving the pain.

R.I.C.E.

A common acronym for acute injury treatment is RICE, which stands for rest, ice, compression, and elevation.

• Rest: Getting proper rest is an extremely important aspect of injury recovery, regardless of if the injury occurred to a muscle, tendon, ligament, or bone. Once injured, further activity that stresses the injured area must be stopped until the injury is allowed to recover over a period of time. Recovery time varies based on the particular injury, but the need for rest following an injury is universal. Be sure to give your body plenty of time to recover following any injuries.
• Ice: Ice is a very effective tool for acute injuries. Cold contact provides short-term pain relief to an injured area, and also works to limit swelling by reducing the overall amount of blood flow to the injured area of the body. Always wrap ice in a cloth to avoid placing it directly on the skin, as this can cause frostbite. Ice should be applied to an injured area for 15-20 minutes at a time, or until the area starts to feel numb. You can apply ice multiple times throughout the day, but take a break of at least 30 minutes between icings.
• Compression: Compression is also important for post-acute injury treatment. Compression helps to reduce and limit overall swelling. Compression also occasionally works to ease the pain. Wrapping an injured area in a bandage is a good way to provide consistent compression to an injured area. Keep in mind that the bandage should be snug but not too tight. If the skin below the bandage looks blue, or is cold, numb, or tingly, then loosen the bandage.
• Elevation: Elevating an injured area after an injury occurs can also help to control overall swelling. Elevating is most effective when the injured area of the body is raised above heart level whenever possible. This helps to control blood flow to the area, and thus reduce swelling.

How Is Chronic Pain Treated?

Chronic pain is usually managed with a combination of treatment strategies, which may include:

• Over-the-counter pain medication
• Prescription pain medication, in severe cases
• Heat and cold therapy
• Injections such as corticosteroids
• Physical and occupational therapy
• Electrical stimulation
• Surgery, depending on the condition
• Antidepressants
• Therapy to help manage the mental health implications of chronic pain
• Alternative medication
  

How Is Subacute Pain Treated?

People with subacute pain tend to do better when treatment combines strategies such as medication, physical therapy, and occupational therapy.

Summary

Acute, chronic, and subacute are terms used to describe the duration of pain. Acute pain is pain that comes on at once and is usually caused by an injury or sudden illness. Chronic pain describes pain that continues for more than three months. Subacute pain describes pain that has a longer duration than acute pain but does not last as long as chronic pain.

Acute pain is usually treated with pain management and RICE (rest, ice, compression, and elevation), and by treating the underlying cause. Subacute and chronic pain are usually treated with a combination of therapies, which may include pain medication, injections, surgery, physical therapy, and/or mental health care.