When you live with persistent pain, injections can sound appealing.

They may offer the possibility of reducing pain without surgery or adding more medication. Equally, some people arrive in pain clinic having already had several injections, sometimes with disappointing results, and understandably wonder whether there is any point in trying another.

The answer is rarely simply injections work or injections don't work.

Different injections do different things. They target different structures and pain mechanisms, and the reason for doing an injection matters just as much as the injection itself.

Injections are precision tools. They are most useful when we have a clear question we are trying to answer or a particular problem we are trying to influence.

An injection should have a purpose

Before considering an injection, I usually start with a different question:

What are we hoping this injection will achieve?

Sometimes the aim is primarily to reduce pain.

Sometimes an injection can help us understand where pain is coming from.

And sometimes the most valuable outcome is not simply a lower pain score, but creating a period in which someone can move more comfortably, sleep better, participate in physiotherapy or begin rebuilding confidence in their body.

That distinction matters.

An injection that reduces pain temporarily but changes nothing else may have limited long-term value. A period of partial pain relief that allows somebody to return to movement and rehabilitation can be much more useful.

Not all injections are the same

“Pain injection” covers a surprisingly wide range of treatments.

Depending on the clinical problem, an injection might target a joint, a nerve, the area around a nerve root, a small nerve supplying a spinal joint, a muscle or another painful structure.

Some contain local anaesthetic, some contain steroid, and some use both. Other procedures use needles for a different purpose altogether — for example, radiofrequency treatment uses carefully positioned needles to treat particular nerves with heat rather than simply injecting medication.

The appropriate treatment therefore depends on what we think is contributing to the pain, rather than simply where it hurts.

Sometimes an injection helps with diagnosis

This is one of the less obvious roles of injections.

Scans are enormously useful, but an MRI cannot always tell us which structure is responsible for pain.

Many of the changes seen on scans — including disc degeneration, facet joint arthritis and other age-related changes — can also be present in people who have little or no pain.

In some circumstances, carefully placing local anaesthetic around a particular nerve or structure can provide additional information.

For example, before considering radiofrequency treatment for pain thought to arise from the small facet joints of the spine, we can temporarily numb the nerves supplying those joints. If someone's usual pain improves significantly while the local anaesthetic is working, that can support the decision about whether radiofrequency treatment is likely to be worthwhile.

In this situation, the temporary nature of the relief isn't a failure.

The injection has answered a clinical question.

What about steroid injections?

Steroids are powerful anti-inflammatory medicines and can be useful in appropriately selected situations.

Examples include injections around an irritated spinal nerve root, some painful joints and certain inflammatory musculoskeletal problems.

But steroid is not a general-purpose treatment for persistent pain.

If inflammation is not an important part of the problem, repeatedly adding steroid is unlikely to solve it. There are also potential side effects from steroid exposure, particularly when injections are repeated.

That is why the decision to use steroid should be based on the clinical situation rather than an assumption that every pain injection needs to contain it.

How long should an injection last?

This is understandably one of the questions I am asked most often.

Unfortunately, there isn't a reliable answer.

Some injections are deliberately short-lived because they are being used diagnostically. Some people experience meaningful relief for weeks or months following a therapeutic injection. Others notice very little improvement.

The duration of benefit depends on the condition being treated, the purpose of the injection, the medication used and individual response.

I am therefore cautious about promising that an injection will provide a particular number of months of relief.

Instead, I prefer to discuss what a realistic useful outcome would look like for that individual person.

Pain relief can create an opportunity

One of the most useful ways to think about an injection is as an opportunity rather than an endpoint.

Persistent pain often leads to a gradual reduction in activity. Muscles become weaker. Movement becomes guarded. Confidence falls. Sleep may deteriorate. Activities that once happened automatically begin to feel risky.

Reducing one important source of pain can sometimes interrupt that cycle.

If an injection gives someone a window of improved comfort, we can use that period deliberately — perhaps to progress physiotherapy, increase walking, return to swimming, improve strength or simply rediscover that a particular movement is possible.

This is why I often work alongside physiotherapists and other practitioners following interventional treatment.

The injection and the rehabilitation are not competing treatments. They can support each other.

When might an injection not be helpful?

Knowing when not to perform an injection is an important part of interventional pain medicine.

An injection may be unlikely to help if there is no convincing structure or mechanism to target, if the proposed treatment does not fit the pattern of symptoms, or if another medical problem needs investigating first.

There are also situations where pain has become widespread or is being driven by several different mechanisms. Treating one small anatomical structure in isolation may then have relatively little effect on the person's overall experience.

That doesn't mean the pain isn't real.

It means we need a treatment strategy that matches the complexity of the problem.

Occasionally, the most useful conclusion from a pain consultation is therefore that an injection isn't the right treatment.

What if I've had an injection before and it didn't work?

A previous unsuccessful injection doesn't necessarily mean that all injections will be ineffective.

It can be useful to understand exactly what was done, where the injection was placed, what medication was used and what the intended purpose was.

Even the response to an unsuccessful treatment can provide useful information.

On the other hand, repeatedly performing essentially the same injection when it has consistently failed to help rarely makes sense.

The question is not simply Have you had injections before?

It is what did we learn from them?

Injections should sit within a bigger plan

Persistent pain rarely has a single solution.

Medication, movement, rehabilitation, sleep, psychological wellbeing, pacing, understanding pain and addressing specific underlying conditions can all matter. For some people, a carefully selected intervention can also be an important part of that picture.

My approach is therefore not to decide that somebody “needs an injection” before meeting them.

We start by understanding the pain, its impact and what may be contributing to it.

Then we can decide together whether there is something useful to target — and, importantly, what we would do with any improvement the injection creates.

Because the aim isn't simply to perform a procedure.

The aim is to help you do more of what matters to you.

Disclaimer:
This article provides general information and does not replace individual medical assessment or advice.