Targeted Solutions Simplify Widespread Itch Management

Effective management of sometimes-debilitating itch starts with understanding type. Matthew J. Zirwas, MD, offered tips for diagnosing and treating widespread itch with little or no rash as part of his presentation at the recent New Wave Dermatology Conference.¹

"Itch is an interesting space,” Zirwas told Dermatology Times®. “It gets more and more complicated the more we know about the mechanism but simpler and simpler in terms of managing itch. There are some really helpful things that most people in dermatology just aren't aware of that I love teaching about."

Zirwas, who is associate professor at Ohio University Heritage College of Medicine in Athens, Ohio, covered the new research on itch and practical recommendations for translating that to patient care. Here are his tips for addressing the unique characteristics of widespread itch that does not present with an obvious rash.

Diagnosis Tips

ZIrwas noted there is “no identifiable cause in the vast majority of [these] cases.” When there is, “It is usually a diagnosis that predated the start of the itch. It is in the medical history, not something you’re going to diagnose because of the itch.”

For cases with itch that “is all over, all the time,” he advised first “considering and usually ordering” these tests: complete blood count, comprehensive medical panel, thyroid stimulating hormone (TSH), hemoglobin, and a1C. “If merited by the individual case, I would consider, but rarely order, hepatitis B and C, HIV, TSH, and a chest X-ray.”

However, in some patients with persistent, widespread itch, it may be necessary to weigh whether to test for cancer, he added. “The only over-represented [types] are bile duct malignancy and hematologic malignancy,” he said. “If you suspect that, order age-appropriate malignancy screens, do a lymph node exam, conduct a complete review of symptoms, and work up any abnormals aggressively.” However, he cautioned, “Don’t go fishing if the review of systems is normal.”

Treatment Strategies

Overall, Zirwas rated butorphanol as “the single most effective treatment for itch.” He noted that studies showed it works in 80% of patients—usually within minutes and lasts 6 hours.

“Theoretically, it does have abuse/dependency possibilities, but that seems much lower than opioids due to its unique mechanism of action and short half-life,” he said.

For generalized itch, Zirwas said it is “reasonable” to give patients a 3-week steroid taper to show improvement. “If they do, find the minimum dose to relieve itch and use it chronically,” he said. A prednisone equivalent of 10mg should be prescribed every other day or less, he noted.

Although he has both male and female patients who have responded to this dosing regimen for prednisone without major side effects, it is not the right choice for every patient. “If prednisone works but the necessary dose is too high, something like methotrexate is worth a trial.” The starting point could be 5 to 10mg weekly which, said Zirwas, “increases the activity of regulatory T-cells so it isn’t suppressing the immune system, it’s balancing it.”

Dexamethasone is another option. “I’ve found that 0.75 or 0.5mg can be used 10 days on and 4 days off. The .75 mg dose equals the efficacy of 25 mg of prednisone with the side effects of 5 mg,” Zirwas said.

Based on his experience, he offered these suggestions when therapeutics can play a role in addressing widespread itch with little or no rash:

• Mirtazapine
• Butorphanol nasal spray
• Gabapentin
• Pregabalin
• SSRIs
• Naltrexone

Treatments he recommended to help address the sleep-related effects of itch include:

• Mirtazapine 7.5 – 15 mg qhs
• Gabapentin 100 – 1200 mg qhs
• Trazodone 25 – 50 mg qhs

“Doxepin and hydroxyzine are effective sleep aids but they don’t help much with itch unless it is histaminergic. They have the most side effects of anything you can prescribe to help people sleep,” he added. “The 3 alternatives listed above work for sleep and itch and are better tolerated.”

Disclosures:

Zirwas is a speaker for Genentech, Novartis, Sanofi, and Regeneron Pharmaceuticals. He is a consultant for Sanofi/Regeneron Pharmaceuticals, FitBit, L’Oreal, LEO Pharma, Pfizer, Eli Lilly and Company, Arcutis Biotherapeutics, Ortho Dermatologics, Sol-Gel, Bausch Health, and EPI Health. He is an investigator for Sanofi/Regeneron Pharmaceuticals, LEO Pharma, Janssen Pharmaceuticals, Incyte, Vyne Therapeutics, UCB, Pfizer, Eli Lilly and Company, Asana Biosciences, Avillion, AbbVie, Edesa Biotech, Galderma, Dermavant, Arcutis Biotherapeutics, EPI Health, and Concert Pharmaceuticals. He is part owner of AsepticMD.

References:

1. Zirwas MJ. Scratching the itch. Presented at: New Wave Dermatology Conference. April 28-May 1, 2022. Coral Gables, Fl.