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Volume2 Issue4
S
upporting
Y
our
P
ractice
Treatment
Common Initial Treatments
1.
Refer thepatient toaprimarycarephysician for antiviral
therapy:
• Acyclovir 800mg (orally, 5 timesdaily for 7–10days)
• Famciclovir 500mg (orally, 3 timesdaily for 7days)
• Valacyclovir 1000mgor 1G (orally, 3 timesdaily for 7
days).
• Brivudin125mg (orally, 1 timedaily for 7days; not
approved for use inCanada)
2.
Painmanagement isoneof themost important factors in
themanagement of acuteherpes zoster infection. Always
consider prescribinganticonvulsants formanagement of
neuropathicpainconditions, aspatientsdonot respond
well to stronganalgesics suchasopioids.
• Gabapentin600–900mg (orally, 1 timedaily for 10
days)
or
300mg (orally, 2or 3 timesdaily for 10days)
• Pregabalin75mg (orally, 2 timesdaily for 10days)
• Nortriptyline25mg (orally, 1 timedaily at bedtime,
increasing thedosageby25mgevery2–3days as
tolerated)
• Amitriptyline25mg (orally, 1 timedaily at bedtime,
increasing thedosageby25mgevery2–3days as
tolerated)
• Oxycodone5mg (orally, 4 timesdaily for 10days)
• Tramadol 50mg (orally, 2 timesdaily for 10days)
AlternateTreatments
Corticosteroidshavebeen shown tobeeffective in reducing
durationof pain inelderlypatients.
Somepractitioners, dependingon thepatient’s response,
havealso suggested topical anesthetics for pain relief:
• Benzocaine cream (apply to the affected area2–4 times
daily)
• Lidocaine cream (apply to the affected area2–4 times
daily)
• EMLA® cream (apply to theaffectedarea2–4 timesdaily)
Complications
•
Themost commoncomplicationof acuteherpes zoster is
theprogressionof disease intoaprolongedphase known
aspostherpeticneuralgia. At times, patientspresentwith
postherpeticneuralgia,whichbecomes adiagnostic
challengeas theneuropathypersists after resolutionof the
skinormucosal lesions.
•
Other less commoncomplications includeencephalitis,
herpes zoster–relatedopthalmicuswithdelayedcontralat-
eral hemiparesis,myelitis andVZV-related retinitis.
Investigation
1.
Obtainadetailedpatient history, includinghistoryof
chickenpoxor acuteherpes zoster. If patient reports
historyof VZV, note:
• Locationof lesions
• Lesions involvingdermatomes
• Symptoms associatedwith lesions
• Trigger points that aggravatepain
• Lesions limited to themidline
• Swellingon the affected side
2.
Inquireabout typeof painexperienced (i.e., paresthesia,
dysesthesia, allodyniaandhyperalgesia).
3.
Look for swellingon theaffected side.
4.
Order laboratory tests, suchasdirect immunofluores-
cenceassay for VZVantigenor apolymerasechain
reaction (PCR) for VZVDNA for atypical rash.
Diagnosis
Basedon thepatient’smedical historyandonclinical find-
ings, suchasblisters, swellingand laboratory results,
adiagnosisof acuteherpes zoster canbeestablished.
Unilateral rashes (not crossingmidline) andblisters are key
signs for rulingout thediagnosisof herpes zoster virus
affecting the trigeminal nerve.
DifferentialDiagnosis
•
Herpes simplexvirus
•
Erysipelas
•
Bullouspemphigoid
•
Pemphigus vulgaris
•
Bell palsy
•
Trigeminal neuralgia
•
Postherpeticneuralgia
Fig. 1:
Acuteherpes zoster
affecting theophthalmic
andmaxillarydivisionsof the
trigeminal nerve.
Reprintedwithpermission from
Buttaravoli P.HerpesZoster (Shingles).
In: Buttaravoli P.Minor Emergencies:
Splinters toFractures. 2nded.
Philadelphia (PA):MosbyElsevier;
2007.
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