What’s behind that maddening itch? A medical guide to chronic pruritus

Chronic itching, or pruritus, affects at least one in six adults, and for many the cause remains a mystery, leaving them unable to sleep and desperate for relief. The problem can span from tricky-to-treat patches of skin to an overwhelming urge in intimate areas, and experts say a long-term itch should never be dismissed. Scratching can perpetuate an exhausting itch–scratch cycle, sometimes masking more serious conditions such as liver disease, type 2 diabetes or even cancer.

Last week, GP columnist Dr Philippa Kaye invited readers to share their experiences of persistent itching. The response was overwhelming: accounts described years of torment, failed treatments and misdiagnoses. One 79-year-old man described an unbearable itch on his back that persisted for 12 years despite doctors telling him it would pass. An 88-year-old reader spoke of “four years of hell,” with sleepless nights and depression. Yet experts emphasize there is hope: most itching, when properly diagnosed, can be treated, often with simple emollients or prescription medicines.

From eczema to infections, a range of conditions can trigger itch. Eczema, or atopic dermatitis, affects an estimated 1.5 million people in the UK and features red, cracked patches that can be intensely itchy. The condition commonly begins in childhood and is linked to a fragile skin barrier and an overactive immune response. When the skin dries and irritants penetrate, nerves become more sensitive, intensifying the urge to scratch. Over-the-counter moisturisers, known as emollients, and steroid creams are commonly used to reduce swelling, redness and itching. If itching occurs inside the ear canal, patients are advised against cotton buds, which can worsen dryness; instead, a few drops of olive oil or steroid ear drops from a GP may help.

Fungal infections can thrive in moist skin and provoke persistent itch. The skin hosts fungi such as ringworm and athletes’ foot, which can flare in damp areas like between the toes, the groin or under the arms. Ringworm — a red, circular rash with a raised edge — is a telltale sign. Careful hygiene and moisture control matter, because antibiotics or a weakened immune system can disrupt the skin’s balance and allow fungi to flourish. Mild infections often respond to over-the-counter antifungal creams, but a persistent or widespread infection may require prescription-strength treatments.

Scabies, caused by microscopic mites burrowing into the skin, is making a noticeable comeback in parts of Britain. It spreads through close contact and is notorious for its intense itch, typically worse at night. A rash may take up to eight weeks to appear and is often located in the folds of the elbows, knees, buttocks and between the fingers. Diagnosis rests on the pattern of itching and rash; in uncertain cases, skin scrapings may reveal mites or eggs. Treatment usually involves a medicated lotion applied to the entire body and left on for up to 12 hours, sometimes followed by a prescription tablet. All clothing, bedding and towels should be washed at high temperatures to eradicate lingering mites. The itching can persist for weeks after treatment, but with proper application it will subside.

Shingles, caused by reactivation of the varicella-zoster virus, can also follow years of dormancy. It often begins with tingling or malaise, followed days later by a painful, itchy rash that typically affects only one side of the body. Most mild cases clear within a month, but antiviral drugs are most effective if started within 72 hours of symptoms. In rare cases, shingles can involve the eyes and require urgent ophthalmologic care to prevent vision damage. Early treatment reduces the risk of lingering pain and complications, doctors say.

Itching can also signal thyroid problems. An underactive thyroid (hypothyroidism) slows the turnover of skin cells and reduces oil and sweat production, leaving skin dry and itchy. About five in 100 people in the UK have hypothyroidism, most of them women. Emollients can ease symptoms, but hormone replacement therapy is needed to restore balance. Conversely, hyperthyroidism can cause excess sweating and skin irritation; in some instances, itching may be a side effect of antithyroid drugs, in which case an antihistamine might help. In general, when thyroid hormones are balanced, itching should improve.

Persistent itch can be a clue to elevated blood sugar. Diabetes, often called the silent killer, may manifest as itch around the genitals or other areas, particularly when thrush is present alongside thirst or frequent urination. High glucose can create a yeast overgrowth and promote skin dryness, making itching more likely. For many, reducing blood sugar levels can alleviate itch symptoms, and doctors may test for diabetes when patients report chronic genital itching and related signs.

Itchy palms, meanwhile, can point to liver disease. Bile salts produced by the liver can accumulate and trigger itching anywhere on the body, especially the palms, sometimes worse at night. People with additional signs like yellowing of the skin or eyes and fatigue should seek a liver function test from their GP. Treatments may include cholestyramine to block bile salts, rifampicin or, in some cases, sertraline, though response varies.

A third of people with advanced kidney disease report itching, likely due to toxin build-up. And in some cases, unexplained itching can be an early sign of cancer, including lymphoma, which affects the immune system and can provoke deep, burning itch without a rash. Other warning signs include night sweats, fevers, weight loss and swollen lymph nodes. In rare cases, cutaneous lymphoma causes itch and red patches on the skin itself.

Iron deficiency anemia can also manifest as widespread dry, irritated skin without a visible rash. When red blood cells lack sufficient haemoglobin, tissues may receive less oxygen, intensifying itch. A blood test is advised if there is persistent itch without a rash. While most itchy cases stem from dermatological or systemic causes, doctors emphasise that timely testing improves the odds of identifying treatable conditions early.

One case illustrates how confusing and distressing itch can be until a correct diagnosis is reached. Claire O’Brien-Dutson, a 48-year-old cleaner from Greater Manchester, spent two years with a violent forearm itch that disrupted sleep and daily life. She tried multiple creams and antihistamines with little relief. Through online communities, she learned of brachioradial pruritus, a rare condition thought to be linked to sun damage and nerve issues in the neck or spine. Specialists acknowledge it is rare and poorly understood, and treatments can be limited, though emerging options such as nemolizumab or older choices like amitriptyline may provide some help.

Health professionals stress that most itch can be treated effectively once the cause is identified. Over-the-counter moisturisers and topical steroids can reduce inflammation and itch for many patients, while systemic therapies may be needed for infections, scabies, shingles or thyroid-related itching. When in doubt, a healthcare visit allows for a proper history, examination and, if needed, targeted tests for liver, kidney and thyroid function or screening for diabetes or cancer.

If an itch lasts weeks or months, or if new signs like a rash, swelling, fever, night sweats or weight changes accompany it, patients should seek medical advice promptly. Early evaluation helps distinguish common skin conditions from more serious illnesses and can guide appropriate treatment, reducing the risk of chronic discomfort and complications. While the thought of such a condition can be worrying, medical experts say the majority of chronic itch is not a sign of cancer or another severe disease and is manageable with the right care and timing.