Home / Conditions / Post-herpetic neuralgia
The rash healed. The pain did not. Post-herpetic neuralgia is nerve damage left behind by shingles — and it is treatable well beyond the point at which most people are told to live with it.
It is not shingles. Shingles is the acute illness — the painful blistering rash caused by the chickenpox virus reactivating in a nerve. Post-herpetic neuralgia is what can be left behind afterwards: pain that continues once the rash has gone, because the virus damaged the nerve on its way through.
The distinction matters because it changes the treatment entirely. There is no infection left to treat. The problem is a damaged nerve sending pain signals about skin that has already healed — which is why antivirals do nothing at this stage, and why ordinary painkillers do little either.
It is the commonest complication of shingles, and it is a form of neuropathic pain.
Symptoms sit in the same area the rash occupied — typically a band on one side of the trunk, though it can affect the face, and after Ramsay Hunt syndrome it affects the area around one ear.
By this stage the skin usually looks entirely normal. The rash that started it has healed and often left nothing visible — occasionally some pale scarring, frequently nothing at all. That is one reason the condition gets underestimated by everyone except the person who has it, and it is why the pain is so often met with surprise.
Not everyone who has shingles develops it. The likelihood depends substantially on:
Two things substantially reduce the risk, and both happen before this page becomes relevant:
If you are currently having shingles and the rash appeared in the last three days, that is the priority — see a doctor today rather than reading further.
Clinically, and usually straightforwardly. Pain persisting in the distribution of a previous shingles rash is the diagnosis; no test confirms it and none is normally needed.
Examination maps where sensation has changed and where light touch provokes pain, which establishes how much nerve is involved and gives a baseline to measure treatment against. Investigation is used only where the picture is atypical or another cause needs excluding.
No single treatment works for everyone, and most people need a combination. The important point is that the ladder does not stop at tablets — which is where a good many people are left.
Medicated patches applied over the painful area, cut to fit. They act locally rather than throughout the body, which makes them well tolerated, and they are particularly useful where allodynia is the dominant problem.
Certain anti-seizure and antidepressant medicines calm the abnormal signalling of a damaged nerve. Both are used at doses and for reasons unrelated to their original purpose — being offered an antidepressant here is not a comment on your mood.
They take a few weeks to show benefit and are built up gradually, which is worth knowing before deciding they are not working.
Local anaesthetic, sometimes with steroid, delivered to the affected nerve or nerve root. This can interrupt the pain directly, and is often what makes the difference where tablets have reduced the pain without controlling it.
Where the above has not been enough, treatment can be directed at how the nerve carries the signal. Pulsed radiofrequency alters nerve conduction without destroying the nerve, and neuromodulation changes how pain signals reach the brain.
Both are part of Dr Tung's practice, and this is the tier most people with long-standing post-herpetic neuralgia have never been offered.
Many people recover substantially within a year. Some have symptoms for several years, and in a minority it is permanent without treatment.
Long-standing nerve pain is harder to settle than recent nerve pain, which is an argument for treating it sooner rather than a reason to give up on it if yours is long-standing. People are helped at every stage — but earlier is easier.
Post-herpetic neuralgia is usually managed first by a GP, and for a good number of people patches and tablets are enough. The problem is what happens when they are not — because the next step requires someone who performs the procedures rather than prescribes around them.
Pulsed radiofrequency, nerve treatments and blocks, epidural injections and neuromodulation are among Dr Tung's listed procedures. A clinician who does not perform them can only tell you that medication is the treatment. That is where a great many people with this condition stop — not because the ladder ends, but because nobody showed them the rest of it.
The injection is only as good as the target. Which nerve, at which level, and by which approach depends on where the shingles tracked — a band on the trunk, a facial branch, a nerve root. Establishing that is anatomy, and it is the part that decides whether the block works.
Pain in the same region can come from a compressed nerve root, from muscle trigger points, or on the face from trigeminal neuralgia. A previous shingles episode does not guarantee that the current pain is from it. Getting that right determines which treatment is worth trying.
Where shingles affected the facial nerve — Ramsay Hunt syndrome — the persisting pain has its own anatomy and its own interventional options, including occipital and sphenopalatine nerve treatments. Those are part of the same practice.
One thing worth saying plainly. Most people with this condition are over 60, and persistent pain at that age is too often treated as something to be expected. It is not a normal part of ageing. It is nerve damage with a known cause and a defined set of treatments, and being older is a reason to treat it rather than to accept it.
No. Once the rash has crusted and healed, the infectious stage is over. Post-herpetic neuralgia is nerve damage left behind, not an ongoing infection — which is also why antivirals no longer help.
Because the problem is in the nerve, not the skin. The nerve was damaged as the virus travelled along it, and it now sends pain signals about skin that has healed. Normal-looking skin is expected.
That is allodynia — pain from something that should not hurt. A damaged nerve misreads light touch as pain. It is one of the most disabling features and one of the more treatable.
Often, largely, within a year. Some people have it longer. Treatment reduces the pain meaningfully in the great majority regardless of how long it has been present.
Possibly — vaccination against shingles and starting antivirals within 72 hours of the rash both reduce the risk. That is worth knowing for family members in their 50s and beyond rather than as a reason for regret.
No. Bring a note of when the shingles occurred, where the rash was, every medication you have tried and for how long, and what the pain stops you doing.
Neuropathic pain · Ramsay Hunt syndrome · Trigeminal neuralgia · Myofascial pain · Neuromodulation · Neurosurgery
If tablets have not controlled it, there is a further tier of treatment that most people are never offered — and Dr Tung performs it.
