QUESTION: How are high blood sugar and itching, or pruritus, related in people with diabetes?
Diabetes can contribute to itching, but itching does not automatically mean infection or that diabetes medicine needs a higher dose. High glucose may cause dehydration and dry skin and can increase the risk of fungal and bacterial infections. Itching may also come from eczema, contact allergy, medicines, neuropathy, kidney or liver disease, thyroid problems, or another skin condition. Treatment depends on the cause; antibiotics should not be used unless a bacterial infection is diagnosed.
Answer by Dr. Albana Greca, MD, MMedSc
Hi,
Pruritus is the medical word for itching. Diabetes can make several itchy conditions more likely, but there is no single form of “diabetic itching.” The location, appearance, duration, glucose pattern, medicines, and other symptoms help identify the cause.
When glucose is substantially elevated, the kidneys remove more glucose and water in urine. This fluid loss may contribute to dehydration and dry skin. Dry skin can crack, itch, bleed, and become vulnerable to infection.
Better glucose management may help when persistent hyperglycemia is contributing, but one itchy patch does not prove that treatment is inadequate. Review the actual HbA1c and average glucose and record patterns in a blood sugar log.
Fungal infections are more common when glucose is high. They often cause an itchy red rash with scaling or small surrounding spots, particularly in warm, moist areas such as the groin, under the breasts, armpits, skin folds, between the toes, or around the genitals.
Examples include athlete's foot, ringworm, jock itch, vaginal yeast infection, and candidal skin-fold infection. Diagnosis matters because eczema, psoriasis, irritation, and bacterial infection can look similar. Review vaginal itching with diabetes and our diabetes skin-care guide.
Redness, warmth, swelling, tenderness, pus, fever, or rapidly spreading skin change may indicate bacterial infection. Itching alone does not. Antibiotics do not treat dry skin, allergy, fungal infection, or neuropathic itch and should not be taken without examination.
People with diabetes should seek prompt care for an infected wound, especially on the foot. Read about diabetic foot ulcers and daily foot care.
Sometimes. Nerve-related itch may feel burning, crawling, tingling, electric, or unusually sensitive and may occur without a visible rash. It is often localized rather than widespread. Diabetes is only one possible cause, so a clinician should also consider shingles, spinal nerve compression, and other neurological conditions.
See the guide to diabetic neuropathy symptoms.
If itching is generalized, severe, occurs without a rash, or persists despite skin care, ask about blood count, kidney, liver, and thyroid tests. Our diabetes and kidney guide explains why kidney screening matters.
Moisturize the feet but not between the toes. Inspect the skin daily for cracks, blisters, drainage, color change, and wounds. Do not use household remedies on broken skin.
Ask for a diabetes review if itching occurs with increased thirst, frequent urination, blurred vision, recurrent fungal infections, unexplained weight loss, or consistently elevated readings. Do not increase insulin or tablets solely because the skin itches.
Compare readings with the blood sugar level chart and follow individualized targets. Persistent glucose around 300 mg/dL or higher, ketones, vomiting, or dehydration needs prompt medical assessment; see dangerous blood sugar levels.
Seek urgent care for rapidly spreading redness, severe pain, warmth, swelling, pus, fever, red streaks, black tissue, a foot wound, facial or throat swelling, wheezing, or difficulty breathing. Arrange prompt review for widespread unexplained itching, jaundice, dark urine, marked swelling, reduced urination, recurrent infections, or an itchy lesion that bleeds, changes, or does not heal.
The previous answer incorrectly treated diabetic itching as infection and suggested antibiotics. Diabetes can contribute through dry skin, infection risk, circulation problems, or neuropathy, but the correct treatment may be moisturizer, antifungal medicine, allergy treatment, glucose review, or investigation of another medical condition. Examine the skin before treating it.
Educational safety note: This answer is for general diabetes and skin education only. It does not replace a medical or dermatology examination. Do not change diabetes medicine or begin antibiotics, antifungals, steroid creams, antihistamines, or supplements without appropriate professional guidance.
Last reviewed: July 2026.
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