CLINICAL UPDATE

The Pharmacy First service in England enables pharmacists to diagnose and treat seven specific conditions, with the aim of reducing current pressures on general practice.

This series of guides assumes that pharmacists are familiar with the clinical pathways and requirements for Pharmacy First. The articles explore some key aspects of each service to support and enhance pharmacists’ knowledge.

Here, GP Dr Toni Hazell offers ten top tips on diagnosing and treating shingles in line with the Pharmacy First service.

 

Shingles is a viral infection, caused by reactivation of the varicella zoster virus. When the virus is first caught, it presents as chickenpox, which usually resolves with no treatment. However, the virus then remains in the nerves and can reactivate as shingles, causing a rash which is limited to the area of skin (dermatome) supplied by the nerve where the virus has lain dormant, usually for many years (see image 1).

Image 1. The dermatomes of the human body. Each area is supplied by one nerve and so a shingles rash will typically be confined to one such area (Science Photo Library)

SPL_dermatome_skin_sensory_areas

 

Here are my top tips on how to assess and manage presentations of shingles in non-pregnant individuals aged 18 or over appropriately and in line with the new Pharmacy First service.

1. Rule out serious shingles variants or complications

Always first consider if a patient is unwell enough that they may need hospital treatment. As described in earlier articles in this series, it is important not to rely on the NEWS2 score but look for clinical signs backed up by physiological measures.1 I would be concerned if a patient looks sweaty or feels dizzy, is tachycardic or has a low blood pressure.

Next check for specific types of shingles which might need referral. The latter includes shingles near the eye, for which hospital review is advised (see image 2).2 A rash on the tip, side or root of the nose (Hutchinson’s sign), altered vision or a red eye should raise concerns for this.

Image 2. Shingles rash affecting eye (Science Photo Library)

SPL_Shingles_rash-affecting-eye

 

Complications of shingles should also be considered. The varicella zoster virus can cause serious complications including infection and inflammation of the brain (encephalitis), spinal cord (myelitis) or meninges (the membranes around the brain and spinal cord – meningitis). It can also cause a paralysis of the facial nerve, known as Ramsay Hunt syndrome.3 This will typically present with marked facial asymmetry – the mouth will droop, and the patient will be unable to close one eye.

The Pharmacy First pathway advises referral to the emergency department if any of the above applies.

2. Take a full medical history

It is important to also take a full history about medical conditions and medication – a patient who is immunosuppressed due to medical history (eg, a blood cancer) or due to pharmacological therapy (eg, taken post-transplant or for rheumatoid arthritis) may develop a more widespread infection and need referring on. The Pharmacy First pathway identifies two groups – those who are ‘severely immunosuppressed’ who should always be referred, and those who are ‘immunosuppressed’, who should be referred only if the rash is severe or widespread, or if they are systemically unwell. The pathway does not define ‘severely immunosuppressed’; it may be useful to refer to the list set out by NHS England for early access to the Covid vaccination (see box 1 below).


Box 1. Definition of severely immunosuppressed individuals:4

  • Those with immunosuppression due to disease or treatment, including:-
  • patients undergoing chemotherapy leading to immunosuppression
  • patients undergoing radical radiotherapy
  • solid organ transplant recipients, bone marrow or stem cell transplant recipients
  • HIV infection at all stages
  • multiple myeloma or genetic disorders affecting the immune system (eg, IRAK-4 deficiency, NEMO deficiency syndrome, complement disorder, SCID).
  • Individuals who are receiving immunosuppressive or immunomodulating biological therapy including, but not limited to, anti-TNF, alemtuzumab, ofatumumab, rituximab
  • Patients receiving protein kinase inhibitors or PARP inhibitors, and
  • Individuals treated with steroid sparing agents such as cyclophosphamide and mycophenolate mofetil
  • Individuals treated with or likely to be treated with systemic steroids for more than a month at a dose equivalent to prednisolone at 20mg or more per day for adults
  • Anyone with a history of haematological malignancy, including leukaemia, lymphoma, and myeloma and those with systemic lupus erythematosus and rheumatoid arthritis, and psoriasis who may require long term immunosuppressive treatments.

3. Ask about symptoms accompanying the rash

The varicella zoster virus comes from the same family as the herpes zoster virus which causes cold sores – they are both human neurotropic alphaherpesviruses.5 The patient may therefore describe similar symptoms to that of a cold sore, in that the affected skin feels abnormal for a few days before the rash occurs. It might be described as burning or stabbing or tingling, and the pain can be severe. It might be there all the time, or it might come and go. Some patients (but not all) will feel unwell in this prodromal phase, possibly with a fever or fatigue.

After 2-3 days the rash will appear, and is almost always limited to one dermatome, on one side of the body (see image 3 below). If it crosses the midline, it’s unlikely to be shingles. Note that shingles that appears to affect more than one dermatome is a red flag for immunocompromise;6 it would be wise to refer such patients to the GP (with safety-netting advice) to confirm the diagnosis and consider whether specialist review is needed.

See box 2 for key features of shingles.


Box 2. Key features of shingles3,7

The rash starts with raised red spots on a lighter pink background – they will rapidly become vesicle (small blisters filled with fluid).

New vesicles may continue to appear for a few days.

The blisters might burst, leaking pus or blood, and the area will then dry, leaving a scab.

Depending on the area affected, there may also be tender lymph nodes.


4. Understand why you are prescribing

In an immunocompetent adult, shingles will normally resolve without treatment, so why would we prescribe aciclovir, an antiviral?

There are two aims of treatment. The first is to speed up healing and reduce pain and the second is to reduce the risk of post-herpetic neuralgia (PHN).8 This is an extremely unpleasant complication of shingles, whereby the patient gets neuropathic pain (nerve pain) in the area where they had the rash. It is caused by nerve damage – symptoms may fade with time, but it cannot be cured and over half of people with PHN have pain for over a year, with many not experiencing pain relief from the treatments available. The ongoing pain can have psychological consequences, with one study showing that over two-thirds of a cohort of patients with PHN developed anxiety or depression.9,10 Treatment with aciclovir doesn’t necessarily prevent PHN (though it may reduce severity) and studies in this area are sometimes conflicting,11-13 but NICE advises aciclovir treatment partly to reduce the risk,2 particularly in those over the age of 50, in whom PHN is more common.

5. Consider antivirals for recent rash onset

The antiviral aciclovir is recommended in most cases and this is usually well tolerated, with adverse effects being self-limiting – they may include nausea, vomiting, headache and fatigue. More serious adverse effects such as ataxia, encephalopathy and psychosis occur at a rate of 1 in 1000 to 1 in 10,000.14,15 However, as any drug can have adverse effects, we should only prescribe where the drug is likely to give benefit. For most patients with shingles, this is the case if the rash has started to appear within the last 72 hours (albeit the prodrome of tingling, pain or fatigue may have lasted longer than that).

For those over 70, or who have a background severe skin condition, it may be worth prescribing up to a week after the onset of the rash. The same applies for treatment of an immunocompromised patient; note in this case you should also inform their GP practice by email or phone call, requesting a GP review.

Image 3. Shingles rash on chest of elderly man (Science Photo Library)

SPL_Shingles_rash-on-chest

 

See box 3 for full details of eligibility for treatment with antivirals, and point 6 for more information about the choice of antiviral.


Box 3. Eligibility for antiviral treatment

Rash has started in the last 72 hours and one of the following criteria applies:

  • Patient is immunosuppressed.
  • There is shingles on the neck, limbs or perineum.
  • There is moderate to severe pain or a moderate to severe rash (the terms moderate or severe are not defined, so clinical judgment is necessary).
  • The patient is aged over 50.

Rash has started in the last week and one of the following criteria applies:

  • Patient is immunosuppressed.
  • New vesicles are continuing to form.
  • The pain is severe.
  • The pain has a severe skin condition such as eczema.
  • The patient is aged 70 or over.

6. Consider adherence and immunocompromise in choice of antiviral

Most patients will be offered aciclovir, taken at a dose of 800mg five times a day for seven days.

It is however well known that patients are less likely to fully adhere to medication which must be taken more than once a day,16,17 so adherence risk is given as a reason to prescribe valaciclovir instead. This should be considered for patients who need assistance to take their medication or are already taking eight or more medications per day.

Valaciclovir is taken at a dose of 1,000mg three times per day, also for seven days;18 it should also be offered to those who are immunosuppressed, although as already noted, in many cases it will be appropriate to refer those who are immunosuppressed rather than treating under Pharmacy First.

7. Advise appropriate pain relief

Those who are not eligible for antivirals should be given information and safety-netting advice, using the British Association of Dermatologists (BAD) leaflet19 and should be signposted to take over-the- counter analgesia, such as ibuprofen, paracetamol or co-codamol.

If pain does not improve with these then consider signposting to general practice, or think about whether this might indicate moderate or severe pain which may make the patient eligible for aciclovir, if they are still within the appropriate timescale.

The BAD leaflet also recommends lidocaine 5% ointment, which can be bought over the counter, or capsaicin cream, which needs to be prescribed.

8. Try to prevent future episodes

It is always worth patients being vaccinated against shingles, even after they have had one episode, and the eligibility for this vaccine was expanded in 2023.

Eligibility is by age, with the eventual aim being to offer it to everyone aged 60 or over. This is being rolled out in a phased way and the vaccine is currently offered to those aged 70 to 79, those who turned 65 on or after 1 September 2023 and those who are 50 or over and severely immunocompromised.20-22 The vaccine is given at the GP surgery.

9. Don’t forget to safety-net

In addition to treatment considerations, it is important to offer advice on self-care, patient information and safety-netting (as described earlier). Safety-netting advice to seek help if symptoms worsen is particularly important for those who are immunocompromised.

10. Consider the wider public health issues

It is a commonly held urban myth that you can catch shingles from chickenpox, but remember shingles is specifically due to reactivation of virus that has lain dormant. It is, however, possible for a person who hasn’t had chickenpox before, or the chickenpox vaccine, to catch chickenpox from someone who has shingles, as the vesicle fluid in shingles rashes contains the varicella virus.23

Those for whom the rash cannot be covered should stay off work or school until the rash has dried out, but there is no need for everyone to avoid work; if the rash can be covered, and the patient feels well enough to work, then they do not need to stay home.23,24

This is the latest in a series of articles on aspects of Pharmacy First from The Pharmacist.  

Dr Toni Hazell is a GP in north London

References
  1. Burns A. NEWS2 sepsis score is not validated in primary careBMJ2018;361:k1743
  2. NICE CKS. Shingles. Jan 2024
  3. Crouch A, Hohman M, Moody M et al. Ramsay Hunt Syndrome. [Updated 2023 Aug 28]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-.
  4. NHS England. Coronavirus documents. JCVI cohort 6 operational guide. Immunosuppressed patients. 2021
  5. Kennedy P, Rovnak J, Badani H et al. A comparison of herpes simplex virus type 1 and varicella-zoster virus latency and reactivation. J Gen Virol 2015 Jul;96(Pt 7):1581-602
  6. Jung T, Hong C, Shin J et al. Multidermatomal herpes zoster involving CN V3 and C2 territories with simultaneous vestibulocochlear deficit: a case report. Medicine 2023 Jul 25;4(7):e284
  7. Primary care dermatology society. Herpes zoster (syn.shingles). Dec 2021
  8. NICE CKS. Post-herpetic neuralgia. April 2022
  9. Du J, Sun G, Ma H et al. Prevalence and risk factors of anxiety and depression in patients with postherpetic neuralgia: a retrospective study. Dermatology 2021;237(6):891-895
  10. Kimura T. Suicide attempt in a patient with post-herpetic neuralgia: a case reportJournal of Japan Society of Pain Clinicians 2012;19(1):40-43
  11. Chen N, Li Q, Yang J et al. Antiviral treatment for preventing postherpetic neuralgia. Cochrane Database Syst Rev 2014; 2014(2):CD006866
  12. Jackson J, Gibbons R, Meyer G et al. The effect of treating herpes zoster with oral acyclovir in preventing postherpetic neuralgia. A meta-analysis. Arch Intern Med 1997; 157(8):909-12
  13. Watson P. Postherpetic neuralgia. BMJ Clin Evid 2010 Oct 8;2010:0905
  14. Aciclovir. Feb 2024
  15. Adverse reactions to drugs. Feb 2024
  16. Baryakova T, Pogostin B, Langer R et al. Overcoming barriers to patient adherence: the case for developing innovative drug delivery systems. Nat Rev Drug Discov 2023 May;22(5):387-409
  17. Srivastava K, Arora A, Kataria A et al. Impact of reducing dosing frequency on adherence to oral therapies: a literature review and meta-analysis. Patient Prefer Adherence 2013 May 20;7:419-34
  18. Valaciclovir. Feb 2024
  19. British Association of Dermatologists. Shingles (herpes zoster). May 2020
  20. NHS shingles vaccine will be offered to almost one million more people. July 2023
  21. Shingles vaccine. Sept 2023
  22. Green book. Shingles (herpes zoster). July 2023
  23. Shingles. Nov 2023
  24. Occupational health consultancy. Working with chickenpox or shingles. March 2023