Objectives. VZV breaks out of the nerve cell body and travels down the nerve axons causing an infection of the skin in the region of the nerve

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1 Deena B. Hollingsworth MSN, FNP-BC ENT Specialists of Northern Virginia Falls Church, Virginia Objectives Describe common signs and symptoms of herpes zoster Discuss the pathophysiology and diagnosis of herpes zoster involving the head and neck A virus by any other name Herpes Zoster Zoster Shingles Zona Ramsey Hunt Discuss the pharmacologic management of herpes zoster Participate in an interactive discussion of the care of patients with herpes zoster. Cutaneous eruption of a viral disease characterized by a painful, unilateral, linear rash. Chicken pox Caused by varicella zoster virus ( VZV) Original infection acute, short lived Usually in children VZV becomes latent in the nerve cell bodies without symptoms Reactivates years later as zoster VZV breaks out of the nerve cell body and travels down the nerve axons causing an infection of the skin in the region of the nerve Can spread from one or more ganglia and infect the corresponding dermatome

2 More common in individuals: over age 60 Varicella infection under 1 year Immune compromised Signs & Symptoms Early symptoms are nonspecific and may lead to incorrect diagnosis (headache, fever, malaise) Followed by sensations of burning pain, itching, hyperesthesia, or parathesia Pain can vary from mild to extreme in the affected dermatome Stinging, tingling, aching, numbing or throbbing sensations with intermittent quick stabbing pain Initial phase pain, parathesia Lasts 1-2 days but up to 3 weeks Rash appears more commonly on the torso but follows the affected dermatome face, eyes, ears,neck Often painless in children Rash starts as red patches followed by small blisters Blisters break to form small ulcerations that begin to dry and form crusts Photos: Dermnet.com

3 General ill feeling Abdominal pain Chills Joint pain Lymphadenopathy Visual problems Taste problems Other Symptoms Loss of eye movement Hearing Loss Herpes zoster ophthalmicus Involves the orbit of the eye 10-25% of the cases Caused by reactivation in the ophthalmic branch of the trigeminal nerve Conjunctivtis Keratitis Uveitis Herpes zoster oticus Ramsey Hunt Syndrome type II Results from the virus spreading from the facial nerve to the vestibulocochlear nerve Hearing loss Vertigo Zoster sine herpete Vesiculation/ulceration of external ear & ipsilateral anterior 2/3 of tongue and soft palate Classic Ramsey Hunt Syndrome Vesicular rash of ear /mouth Facial paresis or paralysis Vertigo and ipsilateral hearing loss Tinnitus Otalgia Headaches Dysarthria Gait ataxia Fever Cervical adenopathy

4 Complete history Diagnosis Skin exam ( unique presentation) Lab studies/ otologic studies Tsanck smear does not differentiate between HSV and VZV Specific IgM antibodies to VZV present only during active infection ( chickenpox or shingles) Audiometry- SNHL Unilateral caloric weakness on ENG Weakness or absence of nerve excitability Zostavax ( live vaccine) Prevention 2005 New England Journal of Medicine decreased incidence by ½ and post herpetic neuralgia by 2/ Vaccine projected a significant annual savings in health care costs ( million) As of October 2007 officially recommended for healthy adults 60 yrs of age or older Exposure to children with chickenpox provides a natural boost Treatment Goals Limit the severity and duration of the pain Shorten the duration of the shingles episode Reduce complications Understanding Neuropathic Pain Nociceptive Pain Terminology Nociceptive pain Neuropathic pain Acute pain Chronic pain

5 Neuropathic Pain Produced by damage to nerve fibers Continuous or paroxysmal Hallmarks are chronic allodynia and hyperalgesia Only partially responds to opioids Examples: trigeminal neuralgia, post herpetic neuralgia, phantom limb pain Acute Pain Self limiting Provides a warning of ongoing tissue damage Symptom of a disease process Minimal psychological sx Nociceptive in nature Caused by chemical, mechanical or thermal stimulation of pain receptors Unrelenting Chronic pain No protective biological function Is the disease process Chronic anxiety, depression, insomnia, impaired social interaction Neuropathic ( involves damage to the central or peripheral nervous system) Tricyclic antidepressants Amitriptyline (Elavil) Inhibits norepinephrine and serotonin reuptake Effective in 2/3 of patients Dosage: Up to mg at bedtime. Start with 10 mg and titrate up. Taper to dc. Side Effects: severe dry mouth, sedation, trouble thinking and dizziness Metabolism: Primarily in liver CYP450. Excreted in urine and stool Tricyclic antidepressants Nortriptyline ( Pamelor) Inhibits norepinephrine and serotonin reuptake Effective in 2/3 of patients Dosage: Up to 150 mg at bedtime. Start with mg and titrate up. Taper to dc. Side Effects: severe dry mouth, sedation, blurred vision, constipation, urinary retention, trouble thinking and dizziness Metabolism: Primarily in liver CYP450. Excreted in urine and stool Tricyclic antidepressants Desipramine (norpramin) Inhibits norepinephrine and serotonin reuptake Effective in 2/3 of patients Dosage: Up to 150 mg at bedtime. Start with mg and titrate up. Taper to dc. Side Effects: severe dry mouth, sedation, blurred vision, constipation, urinary retention, trouble thinking and dizziness Metabolism: Primarily in liver CYP450. Excreted in urine and stool

6 Anticonvulsants Gabapentin (Neurontin) Very effective, considered first line Mechanism of action unknown Does not interact with many other medications Dosage: mg tid. Start with 300 mg first day, increase to bid day 2, increase to tid day 3. Max : mg/d. Taper over 7 days to dc. Side effects: Somnolence, dizziness, edema, dry mouth Metabolism: none - 100% excreted in the urine Anticonvulsants Pregabalin ( Lyrica) Approved by FDA in 2004 specifically for neuropathic pain of DM and shingles Mechanism of action not clear. Thought to reduce neurotransmitter release Dosage: mg /d divided bid /tid. Start with 50 mg tid or 75 mg bid. Increase to 300 mg over 7 d. Max: 600 mg/d. Increase after 2-4 weeks at 300/d ineffective. Taper over 7 d to dc. Side effects: dizziness, sleepiness Metabolism: None 90% excreted in urine Do not use with ginko biloba Opioids Garroway et.al. reported several reviews that found controlled release oxycodone reduced pain by 50% Long acting morphine/methadone and tramadol reduced pain only slightly more than placebo Side effect profile ( constipation, N&V, sedation and dependence) vs efficacy makes these drugs a poor choice. Topical Analgesics Insufficient evidence to support the use of topicals 5% lidocaine patch may be effective in cases with associated allodynia. Needs to be applied 3-4 times/d. Associated with skin reactions. Some use in elderly with small areas of pain. Capsaicin cream 0.075% reduced pain by 20% Associated with paradoxical burning pain. Antivirals Acyclovir ( Zovirax) Most effective if started within 72 hours of onset Inhibits DNA polymerase ( prevents replication) Dosage: 800 mg po 5 times/d for 7 days Side effects: N&V, headache, malaise, dizziness, arthralgia Metabolism: CYP 450 Valacyclovir ( Valtrex) Advantage of tid dosing Antivirals Dosage: 1000mg po every 8 hours for 7 days Side effects: N&V, headache, malaise, dizziness, arthralgia, elevated liver enzymes, thrombocytopenia, neutropenia Metabolism: liver, GI tract Excreted in feces and urine

7 Decreases inflammation Corticosteroids Questions Give larger dose acutely then taper Interacts with multiple medications Contraindicated in severe infections, peptic ulcer disease, hepatic dysfunction References Dublinsky RM. Kabanni H, El-Chami Z, Boutwell C, Ali H. ( 2008) Practice parameter: an evidence based report of the Quality Standards subcommittee of the American Academy of Neurology Garroway N, et.al.(2009) What measures relieve post herpetic neuralgia? Journal of Family Practice 58(7) 384d-f. Johnson RW, and Dworkin RH ( 2003) Clinical Review: Treatment of herpes zoster and post herpetic neuralgia. BMJ 326(7392): 748. Miravalli AA ( 2009) Ramsey Hunt Syndrome. Medscape.com Oxman MN, Levin MJ, et. Al. ( 2005) A vaccine to prevent herpes zoster and post herpetic neuralgia in older adults. New England Journal of Medicine 253(22): Pellisier JM, Brisson M, Levin MJ ( 2007) Evaluation of the cost effectiveness in the United States of a vaccine to prevent herpes zoster and post herpetic neuralgia in older adults. Vaccine 25(49): Richeimer, Steven ( 2000) Understanding Neuropathic Pain. Universe.com. Tyring, SK ( 2007) Management of herpes zoster and post herpetic neuralgia. Journal American Academy of Dermatology 57(6) : Urman CO, Gottlieb AB ( 2008) New viral vaccines for dermatologic disease. Journal of the American Academy of Dermatology. 58(3): PHOTOS Merck Shingle Info.com DermNet.com