Pain
Pain is a symptom of being hurt or sick. It is a bad sensation that is physical and emotional.
Most pain starts when part of the body is hurt. Nerves in that part send messages through senses to the brain. Those messages tell the brain that the body is being damaged. Pain is not just the message the nerve sends to the brain. It is the bad emotion felt because of that damage.
The message that the nerve sends to the brain is called nociception. What is experienced because of the nociception is pain.
Kinds of pain
Pain can be acute or chronic. Acute means it only happens a short time. Chronic means the pain lasts a long time.
Pain can be from different types of injury:
- Cutaneous pain is from damage to the skin. This is the pain a person feels when their wrist is cut with a knife.
- Visceral pain is from damage to the organs inside the body – like the stomach, kidney, and heart. This is the pain a person feels when they have an ulcer.
- Somatic pain is from muscles, bones, and joints. This is the pain a person feels when they sprain (twist) a joint like the ankle.
Pain can also happen when there is no underlying injury or cause. Pain can happen just because the nerves do not work right. This is called neuropathic pain.
Treatments for pain
For most pain, the best treatment is to stop the damage that makes the pain. If the ankle is sprained, doctors tell the person not to walk on it. They tell them to put ice on it. This helps the injury stop. For an ulcer in the stomach, doctors stop the acid made in the stomach. This helps the ulcer to heal.
But many kinds of pain also need medicines to feel better. There are many different kinds of medicines for pain:
- NSAIDs (acronym for non-steroidal anti-inflammatory drug). These medicines decrease the inflammation where the person is hurt. They also work in the brain to decrease pain. Examples are aspirin, ibuprofen, and naproxen. These medicines can make someone sleepy but they are not addictive. They can cause problems with kidneys and with peptic ulcers.
- Opioids are narcotic pain relievers. They do not have the kidney and stomach problems that NSAIDs have. But they can make someone very sleepy and have other potential side effects, such as lack of coordination, inability to concentrate, blurred vision, and weight gain. They can be addictive.
- Acetaminophen (e.g. Tylenol) is not a narcotic or an NSAID. So it is much safer than either one, but can cause liver damage.
- Anti-seizure medicines (also called antiepileptics or anti-convulsants) – many of these medicines work for chronic neuropathic pain. Other pain medicines may not work at all for those kinds of pain. Examples are carbamazepine and gabapentin.
- Anti-depression medicines can also help chronic pain, even if it is not neuropathic pain. This is partly because of an affect on pain itself. But it also helps, because living in chronic pain can cause depression.
There are doctors who specialize in pain management. These are usually anesthesiologists but may also have any one of a number of underlying areas of specialization, such as neurology, physiatry, or internal medicine.
Chronic pain
A new genetic method of treating chronic pain is in the research stage. The idea is to inactivate (turn off) gene HCN2, which plays a key role in chronic pain. Experiments on mice suggest this will work.
Written for younger readers
Pain, in simpler words
This version comes from Wikijunior, a set of books written for children aged 8 to 11. It is shorter and uses plainer language than the article above.
From Wikijunior: Human Body
Pain is an unpleasant physical sensation. It is often caused by stimuli that are damaging or might be damaging if they are applied for a longer period of time. Pain is perceived differently from person to person and has a strong influence on their mood. Pain is often a sign of injury or disease. Usually pain resolves when the cause of it disappears.
Here you will find a lot about pain sensation. But remember, this is not a professional page, but rather an outline.
Pain is very distressing but also has several functions, such as making you realize that something might be wrong with your body. Imagine that you prick your finger with a thorn of a rose. When you feel the pain you quickly withdraw your hand from the rose. Later, when you want to drink, you will take great care of your hurting finger and watch out that you do not touch the glass with it. This is how pain can protect us from damage.
In and on your body, you have very tiny sensors that are called nociceptors. They are so small that you cannot see them by eye. Heat, chemicals and pressure can activate these sensors and make you perceive pain. When you hurt yourself, these sensors are switched on and send a signal to the opposite side of your brain. The signal is transmitted to the brain via nerve cells, also called neurons. Neurons are like very thin wires that connect different parts of the body so that these parts can communicate with each other.
Only when the signal has reached your brain you can interpret it and realize that you feel pain. However, this happens so quickly that it seems instantly to you. Often, your brain directly responds to pain with a reflex action such as the withdrawing of your hand from the rose.
The pain-sensing nociceptors are found all over your body. You have many of them in your skin, in your muscles but also in your organs. Like this, you can feel pain in every part of your body.
All of these sensors are then linked to these very thin wires, the neurons. These wires then send the pain signal through the spinal cord, the highway of the neurons, to the brain.
What do you do when you hit your knee on a chair? You touch your knee and you rub it, don’t you? Some scientists believe that we rub the hurting body part to reduce the pain. They call this “gate control theory of pain”.
This theory is quite complicated. However, to get an idea of it, imagine again the wires called neurons. There are wires that send pain and others that send the rubbing sensation to the brain. These wires reach the brain via the spinal cord. At some point, both wires meet and pass through a place, which you can think of as a gate. This gate has a certain width that decides which signals can go through. If there is only the pain signal, without the rubbing, the gate will let all of the pain through. However, if you also rub your knee, the gate will let the rubbing signal pass but only part of the pain signal. That is why you reduce the pain if you rub your injured body part.
When someone loses a limb through an accident, they sometimes feel pain as if it were in the missing limb. This is called “phantom pain sensation”. How does this happen? One theory explains these sensations by the reorganization of the pain perceiving area in the brain. In your brain there is a specific part that interprets the signal of different sensations, such as pressure, touch and also pain. This so-called primary somatosensory cortex is the receiver of the pain neurons. Within the somatosensory cortex there are different regions responsible for sensing pain in every part of your body. There is a region that perceives pain from your hand, another one pain from your belly and so on. If someone lost their hand, the region that perceived pain from that hand would be taken over by another part of the body, for example the mouth. So, this person would think their hand is hurting when they feel something close to their mouth.
To prevent pain you should be careful while you are playing or doing sports, so you don’t hurt yourself. You should wash your hands to prevent getting a cold and hence a sore throat or other hurting symptoms. You should drink enough water to prevent headaches. You should live healthy to stay with good health and prevent pain from diseases. To live a healthy life you should eat healthy food and do enough physical activity.
Where this page comes from
The article above is adapted from “Pain” on Simple English Wikipedia, by its contributors. We removed reference markers, navigation boxes and tables, expanded measurement templates into readable numbers, and kept the prose otherwise intact. The simpler version is adapted from Wikijunior on Wikibooks.
Both sources are published under CC BY-SA 4.0, so this page is published under the same licence. You may share and adapt it, including commercially, as long as you credit the original and keep the same licence.
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