Itching (pruritus)

A clear guide to understanding why your skin itches, what the common causes are, and in what situations you should seek medical evaluation.

Summary in 60 seconds

• Itching, also called pruritus, is a symptom , not a diagnosis.
• It can appear due to very common causes, such as dry skin, eczema, contact dermatitis, hives or stings, but sometimes it is also related to medications, pregnancy or internal diseases.
• There may be visible lesions from the start, or nothing may be visible and scratch marks may appear later. When it lasts 6 weeks or more , it is considered chronic pruritus. If it is widespread, interferes with sleep, recurs without explanation, or is accompanied by fever, weight loss, jaundice, pregnancy, or difficulty breathing, it warrants medical evaluation.
• Medical evaluation is usually based on medical history, a complete skin examination and, depending on the case, additional tests such as scraping, biopsy or blood tests.

What is it?

Itching, or pruritus, is the sensation that causes the urge to scratch. In dermatology, it is one of the most frequent symptoms, and although it is often due to common skin problems, it can also affect sleep, mood, and quality of life when it persists. If it lasts for 6 weeks or more , it is considered chronic pruritus. Weisshaar 2019 Roh 2022

Itching is a symptom; understanding what causes it is more important than trying to treat it without context.

Why does it appear?

The most common cause is usually related to the skin itself: dry skin (xerosis), eczema, contact dermatitis, hives, insect bites, or infestations such as scabies . In these cases, the skin barrier is compromised, inflamed, or irritated, and scratching usually worsens the itch-scratch cycle. (Nowak 2017, AAD 2024 , NHS 2023)

But not all itching originates in the skin. In some people, it can be associated with kidney disease, cholestasis and other liver problems, thyroid disorders, diabetes, iron deficiency, hematological disorders, pregnancy, neurological causes, or adverse effects of medications . There are also cases in which several factors coincide. Tarikci 2015 Weisshaar 2019 Rupert 2022

How is it presented?

Itching can occur with or without visible lesions . Sometimes the problem begins with red patches, plaques, hives, blisters, or scaling; other times the person only notices itching, and over time, scratch marks, scabs, thickening of the skin, or discoloration secondary to continuous rubbing appear. Determining whether the lesion appeared before the itching or after the scratching is an important part of the evaluation. Rupert 2022 Weisshaar 2019

The location of the itching also matters. The scalp, skin folds, spaces between the fingers, genital area, palms, and soles can point to specific causes. Nighttime itching is not exclusive to scabies, but it may suggest it when accompanied by close contacts/family members with itching, typical lesions, or worsening of symptoms at bedtime. Podder 2021 BAD 2023 AAD 2024

In what diseases or conditions does it usually occur?

General guidance: The following order is clinical and practical, not an absolute rule. Frequency varies depending on age, context, and whether the itching is localized or generalized.

1) Very frequent

• Dry skin (xerosis)
• Eczema / atopic dermatitis
• Contact dermatitis
• Urticaria
• Insect bites or irritation

These causes often explain many everyday symptoms, especially when there is dryness, visible irritation, or a history of sensitive skin. Nowak 2017 AAD 2024 NHS 2023

2) Frequent

• Scabies (mange)
• Skin fungi
• Psoriasis
• Seborrheic dermatitis
• Drug reactions

In this group, context plays a significant role: household infections, use of new medications, scalp or skin fold lesions, or itching that is disproportionate to the visible skin symptoms. Rupert 2022 BAD 2023

3) Infrequent, but clinically important

• Advanced kidney disease
• Cholestasis and other liver problems
• Pruritus of pregnancy, including intrahepatic cholestasis of pregnancy
• Thyroid disorders, diabetes, or iron deficiency
• Some hematological or neoplastic disorders
• Neuropathic or emotionally related pruritus

These are not the most common causes in the general population, but they should be considered when itching is widespread, persistent, without clear lesions, or accompanied by other symptoms . Tarikci 2015 Weisshaar 2019 Rupert 2022 NHS 2023

When should I consult?

Seek medical evaluation if any of these situations occur:

• Itching with swelling of the lips, tongue or throat, or difficulty breathing .
• Itching with fever, significant discomfort, pain, pus, local heat, or very red skin .
• Itching that lasts more than 2 weeks without improvement , recurs frequently, or has lasted for 6 weeks or more .
• Itching all over the body without a clear cause.
• It interferes with sleep or daily life .
• It appears during pregnancy .
• It is accompanied by weight loss, night sweats, jaundice, dark urine, swollen lymph nodes, or a new lump .
• In an elderly person, it appears as generalized itching without obvious lesions .

These scenarios do not automatically indicate a serious illness, but they do warrant further medical evaluation. NHS 2023 AAFP 2022 NHS 2023a Rupert 2022

What NOT to do?

• Don’t assume that «since there are no rashes, it’s nothing.»
• Do not make scratching your main relief strategy: it can worsen inflammation and cause secondary injuries.
• Avoid taking long, very hot showers.
• Do not overuse perfumed soaps, exfoliants, alcohols or harsh “refreshing” products.
• Do not use corticosteroids, antibiotics, or antifungals on your own for weeks without a reasonable diagnosis.
• Don’t forget to check for simple triggers: rough clothing, detergents, cosmetics, recent medications, or living with other people who also have itching.

Scratching may provide relief for a few seconds, but it often prolongs the problem and alters the actual appearance of the skin.

What does a dermatologist usually do?

The first step is usually a detailed medical history : when it started, whether the itching is localized or all over the body, whether it worsens at night, what medications you’ve started, whether other people have symptoms, whether you are pregnant, and whether you have any pre-existing conditions or have recently changed your personal care products. Weisshaar 2019

Next, a thorough skin examination is performed, including the scalp, nails, spaces between the fingers, and any lesions the patient may not have noticed. If persistent or questionable lesions are present, a skin scraping, culture, or biopsy may be ordered. If an internal cause is suspected, a complete blood count, iron studies, kidney and liver function tests, glucose tests, and thyroid function tests are typically ordered, among other tests depending on the context. Rupert 2022 Weisshaar 2019

Frequently Asked Questions

Can itching without hives be due to something internal?

• Not always, but when itching is generalized, persistent, or without clear lesions, it is worth considering non-cutaneous causes as well. Tarikci 2015 Rupert 2022

Does nighttime itching always mean scabies?

• No. Scabies is a significant possibility, but nighttime itching can also be seen in eczema, psoriasis, urticaria, and other dermatoses. Podder 2021 BAD 2023

Do antihistamines work for all itching?

• No. They can help in some cases, but they don’t resolve all types of itching, nor do they replace finding the underlying cause when the condition persists. BAD 2025 Rupert 2022

Does scratching actually make the problem worse?

• Very often, yes. It can damage the skin, increase inflammation, and perpetuate the itch-scratch cycle. BAD 2025 Weisshaar 2019

How long is too long?

• If it doesn’t improve within about two weeks with basic measures, if it keeps recurring, or if it lasts for six weeks or more , it warrants a specialist evaluation. NHS 2023 Weisshaar 2019

Is itching always «normal» during pregnancy?

• It’s not advisable to assume it. Often it’s not serious, but it should be discussed during pregnancy because it can sometimes be related to a liver condition called intrahepatic cholestasis of pregnancy. NHS 2023 Rupert 2022

Bibliography and sources

• Weisshaar E, Szepietowski JC, Dalgard F, Garcovich S, Lambert J, Leslie TA, et al. European S2k Guideline on Chronic Pruritus. Acta Derm Venereol. 2019;99(5):469-506. Available at: https://pubmed.ncbi.nlm.nih.gov/30931482/
• Rupert J, Honeycutt JD. Pruritus: Diagnosis and Management. Am Fam Physician. 2022;105(1):55-64. Available at: https://pubmed.ncbi.nlm.nih.gov/35029946/
• Nowak DA, Yeung J. Diagnosis and treatment of pruritus. Can Fam Physician. 2017;63(12):918-924. Available at: https://pubmed.ncbi.nlm.nih.gov/29237630/
• Roh YS, Choi J, Sutaria N, Kwatra SG. Itch: Epidemiology, clinical presentation, and diagnostic workup. J Am Acad Dermatol. 2022;86(1):1-14. Available at: https://pubmed.ncbi.nlm.nih.gov/34428534/
• Tarikci N, Kocatürk E, Güngör Ş, Topal IO, Can PU, Singer R. Pruritus in Systemic Diseases: A Review of Etiological Factors and New Treatment Modalities. Scientific World Journal. 2015;2015:803752. Available at: https://pubmed.ncbi.nlm.nih.gov/26240837/
• Podder I, Mondal H, Kroumpouzos G. Nocturnal pruritus and sleep disturbance associated with dermatologic disorders in adult patients. Int J Womens Dermatol. 2021;7(4):403-410. Available at: https://pubmed.ncbi.nlm.nih.gov/34632036/
• American Academy of Dermatology Association. 10 reasons your skin itches uncontrollably and how to get relief [Internet] . 2024 Sep 19. Available at: https://www.aad.org/public/everyday-care/itchy-skin/itch-relief/relieve-uncontrollably-itchy-skin
• British Association of Dermatologists. Pruritus (itching) [Internet] . Updated December 2025. Available at: https://www.skinhealthinfo.org.uk/condition/pruritus/
• NHS. Itchy skin [Internet] . Reviewed 19 July 2023. Available at: https://www.nhs.uk/symptoms/itchy-skin/
• NHS. Anaphylaxis [Internet] . Reviewed 21 June 2023. Available at: https://www.nhs.uk/conditions/anaphylaxis/
• British Association of Dermatologists. Management of scabies in the UK: expert guidance consensus [Internet] . October 2023. Available at: https://cdn.bad.org.uk/uploads/2023/10/Scabies-guidance-OCT-2023.pdf