Scabies: what it is, symptoms, how it is caught and treatment

Scabies is an infectious skin disease that causes symptoms such as intense itching, especially at night, and the appearance of small pimple-like blisters in areas such as the armpits, elbow, genitals and spaces between the fingers, for example.

Also known as human scabies, scabies is caused by the Sarcoptes scabiei mite, which is easily transmitted from person to person, through direct physical contact, or through the use of contaminated objects, such as clothing, sheets and mattresses.

Scabies can be cured and treatment must be recommended by a dermatologist, which includes the application of medicines in the form of soaps or lotions such as permethrin and benzoyl, and the oral use of ivermectin. See the remedies recommended for scabies.

Photo of scabies spots all over the body

Main symptoms

The main symptoms of scabies are:

• Intense itching of the skin, which increases at night;
• Presence of small blisters with itchy crusts;
• Fine, wavy whitish or skin-colored lines.

The main places where scabies lesions appear are the abdomen, navel, armpits, elbows, wrists, between the fingers and toes, lower part of the buttocks, folds of the arms, behind the knees, ears, genitals, neck, feet and under the breasts.

In men, lesions generally appear on the genitals, penis and scrotum. While in women, the lesions appear more on the nipples. In babies and very young children, the lesions can look like blisters filled with water and usually appear on the soles of the feet, palms of the hands, scalp, neck and face.

Online symptom test

To find out your chances of having scabies, please select the symptoms you are experiencing:

How to confirm the diagnosis

The diagnosis of scabies is made by a dermatologist by evaluating the person’s health history and observing the lesions.

If you want an evaluation with a doctor, make an appointment with the closest dermatologist in your region:

The assessment of lesions can also be done using dermoscopy, which is an examination in which a device is used that allows the innermost structure of the skin to be observed. Learn more about dermoscopy.

In addition, the doctor may also request a parasitological examination, which is carried out by scraping the lesion, to identify the mite that causes scabies. Although not very common, a skin biopsy may also be ordered to help identify eggs, larvae, feces and mites.

How do you get scabies

The transmission of scabies can happen through direct contact with the skin of people who have the disease or with objects infected with the parasite, such as clothes, mattresses, sheets and bath towels, for example.

It is important to remember that, even when a person has scabies but has no symptoms, the disease can be transmitted to other people.

How the treatment is carried out

Treatment for scabies is done with the use of insecticides, antiparasitics or scabicides, in the form of soaps, creams or oral tablets, such as:

• Permethrin 5%: it is a lotion that must be applied to the entire body once a week, for 2 weeks;
• Benzyl benzoate: in the form of soap, this medicine is applied once a day during the bath, where it will produce a foam that must remain on the skin until it dries;
• Sulfur 6% in petroleum jelly or cream: This medicine is recommended for babies under 2 months of age and must be applied to the entire body for 3 consecutive nights, which must be repeated after 1 week;
• Ivermectin: is a tablet that can be indicated to treat scabies, especially for people who do not respond to treatment with creams or lotions, or the elderly, for example. The recommendation is generally 1 dose of 0.2 mg/kg of body weight, and this dosage must be repeated every 7 and 14 days.

Even when a person with scabies has no symptoms, the disease can be transmitted to others. Therefore, it is important that everyone who has been in direct contact also undergoes treatment.

Home remedies for scabies

Some home remedies that help alleviate the symptoms of scabies include massage with olive oil, rue compresses and baths with chamomile tea. See other home remedies recommended for scabies.

Care during treatment

During treatment, it is important to maintain some precautions to help eliminate mites and prevent the transmission of this infection, including:

• Change and wash clothes, towels and bedding used by the person with scabies daily, with hot water (55 to 60ºC) and iron or place in the dryer;
• Take a bath at least once a day;
• Brush your nails with soap designed to eliminate parasites;
• Avoid sharing clothes, bed linen and bath towels;
• Disinfect objects shared with several people, such as gym equipment, hair combs or chairs;
• Avoid sexual relations and physical contact with other people until treatment is complete;
• Clean the floors of the house well and vacuum carpets and furniture, such as armchairs and sofas.

In cases where it is not possible to wash clothes, you must place them in a plastic bag, leaving it tightly closed for at least 3 days. This measure prevents the mite from feeding, eventually being eliminated.