The Dark Side of Painkillers

Pain is an unpleasant feeling that emerges from the nervous system in response to a damaging stimulus. It can be experienced anywhere on the body and can range from mild or severe. The pain could also be sharp or a dull spread out the pain. Broadly, it can be classified into acute and chronic types, with the latter persisting for a prolonged period.

Nevertheless, pain is an important tool for our brain to communicate with our body as it helps to grab our attention towards a trouble.

The mechanism of pain

Nociceptors are a special kind of nerve cells that are designed to transmit pain signals to our brain. They activate only when a stimulus crosses a particular ‘pain threshold’. So by gently pressing your finger on a knife edge you will feel the sharpness of metal, it’s only when you start putting excessive pressure, the pain threshold is crossed which causes the nociceptors to transmit a signal to the brain leading to the sensation of pain.

Further, when there is an injury or tissue damage, the damaged cells of the body produce arachidonic acid, which is then converted to the prostaglandin hormone with the help of COX-2 (cyclo oxygenase) enzyme. This is part of body’s natural defense mechanism which leads to pain, inflammation & fever. An elevated level of prostaglandin hormone also reduces our pain threshold thereby causing an increased sensation of pain in the affected area.

How do pain killers work?

Pain for a long period of time may alter your daily routine by affecting your sleep, appetite, mood and relationship with others. There is a saying “every problem has a solution”, which is indeed true for pain. There are a number of medicines available in drug stores to get relief from different kinds of pain. Let’s us look at some of their major categories and how they function.

Anti-inflammatory drugs/Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)

These drugs inhibit COX enzymes to prevent the conversion of arachidonic acid to prostaglandins, making the body less aware of pain. COX enzyme is of two types – COX -1 and COX -2. While, COX – 1 is responsible for maintaining a protective layer in the stomach, COX-2 is the one that produces prostaglandin at the site of damage. So while the suppression of COX-2 leads to reduced pain, suppression of COX -1 leads to negative effects on gastrointestinal system causing gastric ulcers and bleeding. Thus, NSAIDs are further divided into two types:

  • Non-selective COX inhibitors: These medicines block both types of COX enzymes. Aspirin, ibuprofen, and diclofenac are common drugs in this category.
  • Selective COX-2 inhibitors: These drugs selectively inhibit COX-2 enzyme, thereby lowering pain and inflammation without affecting COX-1 enzyme. Celecoxib and meloxicam are selective COX-2 inhibitors.


These drugs relieve pain without reducing inflammation. These drugs are also helpful in lowering body temperature. Paracetamol, also known as acetaminophen, belongs to this class.

Opioid analgesics

As opposed to the anti-inflammatory and antipyretic analgesics, opioids do not kill the pain by suppressing inflammatory responses. They instead reduce the sensation of pain by blocking the transmission of nerve impulse carrying the pain signal. They also act on the pain receptors present in the brain and modulate the response to the pain stimulus.

Some of the examples of opioids include morphine, codeine, oxycodone, and methadone.

Depending on the nature & intensity of pain, an appropriate painkiller would be usually prescribed by your physician.

Side effects of painkillers

Much to our dismay, there is another side to the analgesics which is not as good as its therapeutic benefits. Prolonged usage of paracetamol causes liver damage, while NSAIDs may cause gastrointestinal bleeding and allergic reactions. Opioids are commonly associated with sedation, constipation, nausea, vomiting, and dryness of mouth. Physical dependence is also a major adverse effect of narcotic analgesics that leads to drug abuse.

Non-drug therapies to relief pain

There are several non-drug approaches to ease the pain. These can be used depending upon the nature of pain.

Relaxation techniques

The foremost strategy in the management of pain is to take rest or to relax the aching part of your body. Relaxation can be achieved by practicing,

  • Aromatherapy, which involves inhalation of fragrances from herbal oils to relieve stress.
  • Massaging techniques which improve blood flow and soothe spasms.
  • Acupuncture, which involves insertion of needles at various points in our body to stabilize the energy channels in our body.
  • Meditation, laughter therapy and listening to music. These activities are associated with release of endorphins in the body, which act as natural pain killers

Physical therapy

Certain conditions like joint pains or even fibromyalgia can be managed by adopting a specific workout routine. Stretching exercises reduce stiffness and improve flexibility while strengthening exercises can make your muscles stronger. Practicing endurance or aerobic exercises can improve your overall health by working on our heart and lung muscles. Make sure, an expert suggests any exercise routine you adopt.

Heat and cold therapies

Heat can ease pain resulting from muscle tension and physical indolence by improving the flow of blood to the affected area. Heating pads or hot packs are used for localized pain, whereas warm baths or lying on a heating mattress can minimize overall pain. Cold therapy, in contrast, triggers numbness by reducing the blood flow to the affected region. Ice packs or a bag containing frozen elements can be placed over the affected area for a duration of 15 to 20 minutes.

A combination of these therapies has proven to be effective in relieving arthritis related pain.