Experts Explore Causes and Care for Chronic Itch

Chronic itch is more than just a burden; it’s a complex, often misunderstood medical condition that affects millions of people, many who struggle to find answers and effective treatments, as expressed by leading dermatologists and itch experts Shawn Kwatra, M.D., Brian Kim, M.D., and Gil Yosipovitch, M.D.

In a recent discussion with Managed Healthcare Executive, the three shared where the science is going, what’s holding it back and how the healthcare system can better support patients.

Kwatra, chair of dermatology at the University of Maryland School of Medicine, said much of the challenge lies in how we define and group itch conditions.

“One element of this leadership is that we're trying to make a map of human itch subtypes, and where there's similarities between conditions with approvals and non-approvals,” he said.

His team recently patented a blood test that identifies upregulated cytokines using flow cytometry, a step toward a more personalized approach to care.

He believes this kind of phenotyping, supported by biomarker-based trials, could lead to more precise treatments and faster regulatory pathways.

Kim, vice chair of dermatology and lead researcher at the Icahn School of Medicine at Mount Sinai, focused on the access side of the issue.

He debated that the current model—where coverage depends on phase three trials and narrow diagnostic codes—isn’t working for many patients.

“The problem right now is that everything about whether medicines are covered or not is based on line diagnoses that have undergone phase three clinical trials,” he said. “But in reality, a lot of itch conditions over time—post-market, once a drug is already approved—off-label use of those medications demonstrate often very convincing efficacy for those conditions that are not textbook.”

Kim added that he’s hopeful real-world evidence could help justify coverage, even without full-scale trials.

As for Yosipovitch, a professor at the Miller School of Medicine at the University of Miami and pioneer in itch research, the future lies in biomarkers.

While he noted that this field is still evolving, he pointed to recent findings on a neuropeptide called brain natriuretic peptide (BNP), long studied in animal models, which is now emerging as a possible biomarker for chronic itch in humans.

“We saw that this is very highly correlated to chronic itch of undetermined origin, also in elderly itch and in patients with prurigo nodularis,” he said, adding that there’s potential of testing for cytokines and chemokines to better understand the causes of different itch types.

Shifting from biology to environmental and lifestyle factors, Kwatra highlighted the role of diet and pollution in the symptoms of itch.

“One way is that the GI system—what you eat—can actually directly stimulate itch,” he said, adding that his team found different fungal species in the gut microbiomes of certain chronic itch patients.

He also noted that environmental exposures such as pollutants or immune triggers like COVID-19 infection or shingles could contribute to the onset or worsening of itch.

While research is still ongoing in support of these observations, Kim believes clinicians can start addressing some of these issues with patients.

“We have noticed that environmental changes, potentially the allergen environment, has contributed a bit more to itch,” he said. “My personal feeling is that processed foods are probably not good. A lot of our food is pickled, which makes it much more recognizable to our immune system.”

Kim suspects this immune response could be one reason food allergies, and possibly itch, are becoming more common.

However, Yosipovitch urged caution, particularly around diet.

While he agrees that pollutants clearly worsen conditions like eczema, food-related itch is more of an issue.

“(With particular) conditions—I have patients who say, ‘Well, I eat X, Y, Z and I feel more itchy.’ So, there are some conditions where we know it is clearly associated, but not everything we eat causes itch,” he said.

Restrictive diets, especially when not backed by solid evidence, Yosipovitch said he questions “the yield of that, because the majority of these patients really don’t have allergy to all those foods.”