Pfizer launch new drug for neuropathic pain

Pain is a subjective experience and every person experiences pain differently. Pain is defined as an “unpleasant sensory and emotional experience associated with actual or potential tissue damage”.

We know that when you experience a defined injury, for example spraining your ankle, the nerves in your ankle send messages to your brain, saying “I feel pain”. The result is that you limp and rest the injured ankle, or you take medication until the pain subsides.

This is called nociceptive or acute pain and is a protective mechanism of the body that ensures you won't injure yourself further. As the injury heals, the pain subsides and finally disappears completely.

Unlike acute pain, nerve pain is generally chronic, which means it lasts for longer than 3 months and can continue for years. Nerve pain may have no obvious cause, or it may be pain that persists long after the initial injury has healed, and with that part of the body now appearing totally normal.

In addition, somehow nerve pain does not respond to traditional pain medications and people may continue to suffer from pain for prolonged periods of time.

Nerve pain affects millions of people around the world, and can be personally devastating for the people who experience it. People affected by nerve pain describe their pain as “punishing cruel” and “tiring-exhausting.” “The worst pain one can possibly imagine” is what many people who suffer from nerve pain say about their pain.

What causes nerve pain?

According to Pfizer product physician, Dr Fathima Docrat, nerve pain may result from various causes that may damage or imbalance the nerves of the brain, the spinal cord or peripheral nerves. “Certain diseases or conditions may result in damaged or hyperexcited nerve impulses, which continually send pain signals to the brain, sometimes even after healing has occurred. Conditions where this can happen include, neck or lower back related nerve pain, nerve pain resulting from diabetes, from shingles, or cancer-related nerve pain. It can also be related to illnesses that lower the body's immune system, spinal cord injuries, multiple sclerosis or stroke,” says Dr Docrat.

What are the symptoms of nerve pain?

Nerve pain has its own distinct effect and the symptoms described by people suffering from nerve pain are different to acute pain symptoms. Some words that neuropathic pain sufferers use to describe nerve pain are electric shocks, burning, and tingling. Other language used, include a cold, prickly (pins and needles) or itchy sensation, and numbness.

“Nerve pain can happen spontaneously, or be provoked by some sort of stimulus, even a non-painful stimulus, such as light touch. People suffering from nerve pain may be unable to put sheets over their legs or wear pantyhose, as they may be extremely sensitive to pain caused by a light touch stimulus such as clothing, bed sheets, or even a light breeze,” says Dr Docrat.

Why is nerve pain so difficult to treat?

Nerve pain is especially problematic to treat because it is often experienced in parts of the body that otherwise appear normal. It is also generally chronic, severe and is resistant to traditional pain medications, and it can be further aggravated by stimuli, including light touch.

Dr Docrat also notes that despite the large number of people who are affected by nerve pain and the degree of suffering they endure, there does not appear to be agreement regarding the best way to treat the more commonly encountered nerve (neuropathic) pain conditions.

“As no single drug works for all nerve pain and its associated conditions, treatment needs to be individualised for every person suffering from nerve pain. The treatment needs to take into account their medical history, how well they will tolerate the medication, other benefits such as improved sleep, mood and quality of life, and to ensure that the cost is relatively affordable for the benefit the patient gains,” Dr Docrat explains.

She adds that another stumbling block to pain relief is that not all nerve pain is recognised as such, and this means that people are often treated with agents such as nonsteroidal anti-inflammatory drugs, which are usually ineffective in relieving nerve pain.

Classes of medication which have been shown to be effective in some types of nerve pain are some antiepileptic and antidepressant drugs. These medications have been shown to be effective in improving nerve pain and positively influencing sleep and mood disturbances. However, use of some of these medications may be limited by side-effects or complicated dosages.3,5,13,14

“The field of nerve (neuropathic) pain research and its treatment is in the early stages of development. Advances are being made in the science of neuropathic pain and new and improved therapies are becoming available for people who continue to suffer from this disabling condition,” concludes Dr Docrat.

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Solly Mabotha
Pfizer South Africa
PR manager
Tel: 011 320 6113
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