WASHINGTON – Antivirals, rest, and pain management are the Big Three of shingles treatment, and they should be employed early and consistently.
There are ways to tweak response, such as augmenting pain management with antidepressants or anticonvulsants. And a corticosteroid may have a place in the mix for some patients. But the importance of the Big Three can’t be overstressed, Dr. Kenneth Tomecki said at the annual meeting of the American Academy of Dermatology.
“You want to halt the progression of disease and decrease viral shedding,” said Dr. Tomecki of the Cleveland Clinic in Ohio. “But the key to successful treatment is to decrease the severity of pain. It is a strong attendant feature. There will be pain and we need to try hard to keep it as brief as possible. Some patients are stoic and will tell you they don’t need anything for pain. Don’t believe them.”
Dr. Kenneth Tomecki
Managing pain also makes it easier to get patients to relax and slow down. “Rest, rest, rest, and more rest. Rest leads the list. These patients need to slow down and cool it. They have a viral illness and systemic disease. Rest is mandatory.”
Antiviral therapy is a key part of treatment, but only if it’s timely. “If you can get it on board in the first 72 hours, you can increase the likelihood of the rash resolving quickly, limit the pain, and reduce the risk of postherpetic neuralgia by 50%.”
The mainstay of antiviral therapy has been acyclovir, which is effective and inexpensive – about $30 for a 7-10 day course. But its bioavailability is not great, which means patients need to take it five times a day.
Famciclovir and valacyclovir possess more efficient pharmacokinetic profiles, and are just as safe and well-tolerated. Their thrice-daily dosing schedules make them a little more manageable for most patients. They are more expensive (about $100 for a week-long course), but not prohibitively so, Dr. Tomecki said. And both of them are effective, with evidence from a randomized, double-blind, controlled trial showing a similar benefit for acute pain and postherpetic neuralgia (Arch Fam Med. 2000;9:863-9).
“I would say both of the newer drugs work a little bit better than acyclovir, but they are similar to each other,” he said. “My go-to treatment for uncomplicated zoster is 1 gram of valacyclovir three times a day for 7-10 days, and I throw in either gabapentin or pregabalin.”
In an open-label study of 166 patients (Arch Dermatol. 2011;147[8]:901-7), this combination resulted in less than a 10% incidence of postherpetic neuralgia at 6 months, Dr. Tomecki added.
Mild pain during the acute phase can be handled with acetaminophen or nonsteroidal anti-inflammatories. But lots of patients need a bigger bullet for their discomfort. Tramadol at 50 mg/day or a weak opioid will work for moderate pain. With severe pain, start thinking about oxycodone.
A tapered dose of corticosteroid can be included, especially if cellulitis is involved in the clinical picture. “It does help patients feel better, and there’s no real detriment to it,” Dr. Tomecki said.
Patients who have postherpetic pain may need longer-term pain management. Lidocaine patches and capsaicin cream are both effective, and they work best if used consistently. The recommended dosing frequency for capsaicin is three or four times a day, “But to be really effective I find you need to apply it more like five or six times a day.”
Patients with persistent postherpetic pain should probably be referred to a neurologist or pain management specialist. In the meantime, though, tricyclic antidepressants aren’t out of the question, but they take a while to kick in and must be used very, very carefully in elderly patients. “Don’t jump in initially with these. Start with good derm care and rest.”
The anticonvulsants gabapentin or pregabalin can also be helpful. “If you do start any of these, start low, go slow and refer for pain management.”
A 2014 meta-analysis of seven studies, however, showed a mixed bag of benefits and tradeoffs (Minerva Anestesiol. 2014 May;80[5]:556-67). Gabapentin improved sleep quality and significantly reduce pain, but patients who took it were likely to report dizziness, sleepiness, edema, ataxia, and diarrhea.
Antidepressants and anticonvulsants may be out of the purview of many dermatologists, but other pain management strategies are not, Dr. Tomecki said. Among them is cryotherapy.
“I’m not talking about freezing as in truly freezing like with do with actinic keratosis. I’m talking about just a gentle brushing of the area.”
A small study of 47 patients employed a 30-second pass of liquid nitrogen over the affected sensory nerve dermatome, making sure not to freeze the skin (Int J Dermatol. 2011 Jun;50[6]:746-50). The treatment consisted of three passes per session on a weekly basis. Most of the patients (94%) experienced good or excellent improvements by week 6. For 19%, one session was enough to eliminate pain, and 17% had complete pain relief in two sessions.