Scabies
Created: 09.01.2025
Updated 13.10.2026
Approved by: Consultant Dermatologist, Dr James Denny
What is scabies?
Scabies is a highly contagious skin infestation caused by the scabies mite (Sarcoptes scabiei var. hominis). The female mite burrows into the outer layer of the skin, where it lays eggs. The body's immune response to the mites, eggs, and waste products causes the characteristic itching and rash.
Scabies spreads primarily through prolonged skin to skin contact with an infected person. Less commonly, it can spread through shared bedding, clothing, or towels, particularly when these items have been used recently by someone with active scabies.
Scabies affects people of all ages and backgrounds but is more common in households, care homes, schools, and other settings where close physical contact is frequent. Poor hygiene does not cause scabies.
What are the symptoms?
Symptoms usually develop 2 to 6 weeks after the first infestation, although people who have previously had scabies may develop symptoms within a few days.
The most common scabies symptoms include:
- An intensely itchy rash, particularly at night
- Small red bumps or blisters
- Thin, wavy burrow lines on the skin
- Persistent itching that affects sleep
The scabies rash commonly affects:
- Between the fingers
- Wrists
- Elbows
- Armpits
- Around the waist
- Buttocks
- Genital area
In young children and infants, the face, scalp, palms, and soles of the feet may also be affected. Persistent scratching can damage the skin and increase the risk of a secondary bacterial infection, which may require additional treatment.
Crusted scabies
A rare but more severe form known as crusted scabies can occur in people with a weakened immune system, older adults, or those with neurological conditions.
Unlike typical scabies, crusted scabies causes thick, crusted plaques containing thousands to millions of mites. Although itching may be less severe, this form is extremely contagious and requires urgent specialist treatment and infection control measures.
How is scabies diagnosed?
A dermatologist can often diagnose scabies based on the appearance of the rash, the distribution of lesions, and a history of itching or close contact with affected individuals.
In uncertain cases, dermoscopy or microscopic examination of a skin scraping may be used to identify mites, eggs, or mite waste products and confirm the diagnosis.
Specialist dermatology assessment is valuable when the diagnosis is unclear or when symptoms persist despite treatment.
How do we treat scabies?
The aim of treatment is to eliminate the mites and prevent reinfestation.
Topical treatments
Prescription topical treatments are the first-line treatment for most people. Permethrin 5% cream is commonly prescribed and should be applied to the entire body as directed, usually from the neck down, and left on for the recommended time before washing off.
In infants, older adults, or certain patients, the scalp and face may also require treatment under medical guidance.
Oral medication
Oral ivermectin may be recommended for crusted scabies, widespread infestations, or when topical treatment is unsuitable.
Treating close contacts
To successfully treat scabies, all household members, sexual partners, and other close contacts should be treated at the same time, even if they have no symptoms. This helps prevent reinfestation and further spread.
How can you prevent scabies?
To prevent scabies from recurring or spreading:
- Treat all close contacts simultaneously
- Wash recently used clothing, towels, and bedding at 60°C where the fabric allows
- Tumble dry items on a hot setting if appropriate
- Seal items that cannot be washed in a plastic bag for at least 72 hours
- Avoid close skin contact until treatment has been completed
Taking these steps helps prevent the mites from surviving outside the body and reduces the chance of reinfection.
What is the prognosis?
With prompt diagnosis and appropriate treatment, the outlook for scabies is excellent. The mites are usually eliminated after successful treatment, although itching may continue for up to six weeks while the skin's immune reaction gradually settles.
Persistent itching does not necessarily mean treatment has failed. However, new burrows or new lesions developing several weeks after treatment may indicate reinfestation or incomplete treatment. Dermatology review is recommended if symptoms persist, recur, or if crusted scabies is suspected.
Frequently Asked Questions (FAQs)
Is scabies spread through skin to skin contact?
Yes. Scabies spreads mainly through prolonged skin to skin contact with an infected person. It is less commonly spread through shared bedding, towels, or clothing, particularly if these items have been used recently by someone with active scabies.
How long does it take for scabies treatment to work?
The mites are usually killed after the first course of treatment if it is applied correctly. However, itching can continue for up to six weeks because the skin is still reacting to the mites, even though they have been eliminated.
Do all family members need treatment if only one person has scabies?
Yes. Everyone who has had close physical contact with the affected person, including household members and sexual partners, should be treated at the same time to prevent the infestation from spreading or returning.
What is crusted scabies?
Crusted scabies is a rare but severe form of scabies that usually affects people with a weakened immune system. It causes thick crusts containing large numbers of mites and requires urgent specialist treatment because it is highly contagious.
When should I see a dermatologist for scabies?
You should seek specialist advice if symptoms persist after treatment, the diagnosis is uncertain, repeated infestations occur, or crusted scabies is suspected. A dermatologist can confirm the diagnosis and recommend the most appropriate treatment plan.
