Medications for Chronic Pain – All or Nothing?

There are many variations on a theme within each group. All of the medications on the list below have potential side effects both severe and minor, including the Ibuprofen readily available over the counter.

There are broadly speaking, six categories of pain-killing medications:

• Analgesics working on receptors (i.e. Paracetamol, weak opioids and strong opioids)
• Anti-inflammatories (non-steroidals and steroids)
• Muscle relaxants
• Membrane Stabilisers
• Anti-depressants
• Others (e.g. cannabinoids)

In my experience all of these medications have the ability to bring relief of pain to some extent. In combination they are often more effective. There are broad principles of when to use each of these, but for some medications the picture is far from clear: Which patients and for what indications we prescribe cannabinoids, is a work in progress. I doubt it will be the panacea that we would all hope for, but the jury is still out.

In treating patients I find it largely unhelpful to categorise various pain types, though taxonomy has its place, to enable discussions and research. New pain is ‘acute’ for 83 days and becomes ‘chronic’ on day 84. This is an arbitrary division, but does illustrate how poor we are at treating and stopping pain quickly, since there are millions of ‘chronic’ pain sufferers in the UK. Similarly, ‘primary’ and ‘secondary’ are to me at least unhelpful.

Medicine continues to evolve. What we believed to be true yesterday, is no longer true today. For example, a few decades ago, low back pain would have been investigated with a plain film x-ray of the lumbar spine. It shows the bone structures, but only the space where the intervertebral discs are positioned. If the space was the correct height, this may well have been passed as normal. An MRI scan shows the bones, muscles, tendons, ligaments, the lining of the small facet joints and the structure of the discs. Hence we have a greater ability to try and correlate pain with structural damage, that would have been impossible before. Therefore, decades ago we would not have had a clear diagnosis for the pain, but today it is more likely that we do.

I am very concerned about the concept of not utilising all modalities of pain relief, simply because there is no firm diagnosis. The MRI example is on-going: Who knows what more sophisticated investigations may be available in the future, to help understand a patient’s pain state. What may be ‘normal’ by MRI today may not be normal in the future. Is it reasonable to wait a few decades for new technology whilst patients suffer?

As yet we do not have a ‘pain test’. We have x-rays, CT and MRI scans (which are but snapshots) and blood tests, but no actual investigation that demonstrates and diagnoses pain. Indeed, even the current gold standard MRI is open to interpretation. An MRI that shows many structural changes, the inevitable wear and tear of a busy life, may yet belong to somebody with little or no pain. Conversely, a small, subtle structural change may cause significant pain and disability. Why this should be is not understood. It is all too easy to start unhelpful discussions about ‘pain thresholds’ and ‘psychological issues’, implying failure to cope, when the patient’s suffering does not conveniently fit a treatment algorithm.

July 16 2020: The International Association for the Study of Pain (IASP), revised the definition of Pain:

‘An unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage.’

This definition covers both the physical and the psychological pain elements. The two are always present to a greater or lesser extent. I would find it strange for a patient suffering with intrusive untreated physical pain not to feel, miserable, frustrated, tired or indeed angry. Likewise if one is distressed for whatever reason; relationships, bereavement, financial worries and not sleeping, then surely it is not surprising to find it more difficult to cope with physical pain? After 30 years of dealing with patients who have pain, I still find it hard to work out where the balance lies in any particular individual.

IASP qualifies the definition with various additional statements including this one:

‘Pain and nociception are different phenomena. Pain cannot be inferred solely from activity in sensory neurons’.

The underlined section is crucial. This means that the ‘pain experience’ may (or may not) occur with or without pain fibres sending messages to the brain. This demonstrates the complexities of this common problem we call PAIN, despite our scientific advances, still so poorly understood and the broad range of medications that may usefully reduce pain.

We try and address ALL elements where possible:

• If the BMI is high, then TRY and improve diet and weight loss
• If not exercising then TRY to do something: Little and often is the rule and water-based exercise is safest and easiest to make progress
• Ergonomics: Sitting, bending and lifting safely can be learned and put into practice
• Sleep patterns: Without reasonable, restorative sleep all else is very difficult
• TRY and address any issues causing emotional upset. Family, friends and professionals may be able to help with a burden shared.

If an individual can treat the pain by simply tackling the above list, without medications, then of course this is the preferable route. However, it may not be able to address the items on the list until the pain is reduced to some extent, to gain some momentum and motivation. This takes us back to the list of medications at the top.

The rules for any pain medication are the same:

• Start medication ‘A’ with a small dose, in case it causes side effects
• Increase the dose briskly, over days not weeks and months
• Do not discount a medication until either its maximum dose is reached, or side effects occur, in which case it should be reduced and/or stopped
• If medication A is inadequately controlling the pain, then add ‘B’ in a similar fashion
• Monitor the benefits or otherwise of the medications regularly, to make reductions and stop them when possible, or if they become ineffectual

In this way the patient achieves most, from the smallest dose and number of medications possible. If the medications do not help, then more invasive measures may be considered. I always prescribe pain killers in the hope that they will be a ‘means to an end’ and can eventually be stopped. If not then from time to time it is important to reassess the risk vs benefit of the medications and reconsider other ways forward.

Pain is pain. It has many guises, not always clear and often complex in its origins. We are not very good at treating pain as the numbering of people suffering daily clearly indicates. Therefore surely we should at least try the medication options at our disposal to at least diminish the impact of the pain and sooner rather than later.

For further explanations: read this article to look at pain management from a patient’s perspective.