Overview
At first glance, psoriasis and scabies can easily be mistaken for one another. If you take a closer look, however, there are clear differences.
Keep reading to understand these differences, as well each condition’s risk factors, symptoms, and treatment options.
Psoriasis
Psoriasis is a chronic autoimmune disease of the skin. It causes your body’s immune system to attack itself, which leads to the rapid buildup of skin cells. This buildup of cells causes scaling on the skin’s surface.
Psoriasis isn’t contagious. Touching a psoriatic lesion on another person won’t cause you to develop the condition.
There are several types of psoriasis, but the most common type is plaque psoriasis.
Scabies
Scabies, on the other hand, is a contagious skin condition caused by Sarcoptes scabiei, a microscopic, burrowing mite.
A scabies infection begins when a parasitic female mite burrows into your skin and lays eggs. After the eggs hatch, the larvae move to your skin’s surface, where they spread and continue the cycle.
Here are some ways to tell the difference between the two skin conditions:
| Psoriasis | Scabies |
| lesions may or may not itch | lesions are usually intensely itchy |
| lesions tend to appear in patches | lesions tend to appear as burrowing trails on the skin |
| lesions cause skin flaking and scaling | rash typically doesn’t flake and scale |
| autoimmune disease | caused by a mite infestation |
| not contagious | contagious through direct skin contact |
Psoriasis strikes people of all ages, regardless of gender, ethnicity, or lifestyle. Several factors may increase your risk for psoriasis, such as:
- a family history of psoriasis
- a severe viral infection, such as HIV
- a severe bacterial infection
- a high stress level
- being overweight or obese
- smoking
Since scabies is highly contagious, it’s challenging to contain an infestation once it begins.
According to the
Scabies infections are fairly common in:
- childcare centers
- nursing homes
- facilities specializing in long-term care
- prisons
If you have a compromised immune system or you’re disabled or an older adult, you’re at risk of getting a severe form known as Norwegian scabies.
Also called crusted scabies, Norwegian scabies results in thick crusts of skin that contain mites and eggs in large numbers. The mites aren’t more potent than other types, but their high numbers make them extremely contagious.
Psoriasis causes thick, red, silvery patches to form on your skin. Lesions may form anywhere on your body, but they’re most common on these areas:
- the elbows
- the knees
- the scalp
- the lower back
Other symptoms may include:
- dry, cracked skin
- itching
- burning skin
- skin soreness
- pitted nails
Scabies symptoms are caused by an allergic reaction to the mites. If you’ve never had scabies, it can take several weeks for symptoms to appear. If you’ve had scabies and get it again, symptoms may appear within a few days.
Scabies may develop anywhere on the body, but it’s more common on the folds of the skin in adults, such as:
- between the fingers
- around the waist
- the armpits
- the inner elbow
- the wrists
- around the breasts in females
- the genital area in males
- the shoulder blades
- the buttocks
- the back of the knees
In babies and young children, scabies is often seen in one or more of the following areas:
- the scalp
- the neck
- the face
- the palms
- the soles of the feet
The main symptom of scabies is intense and uncontrollable itching, especially at night. You may also see tiny tracks on the skin made of blisters or pimplelike bumps, which are where the mites have burrowed.
Although psoriasis isn’t contagious, it isn’t curable either. Treatments are aimed at reducing symptoms and improving the appearance of your skin.
Depending on the type and severity of your psoriasis, different treatments may be necessary.
Doctors may recommend any of these treatments:
- oral medications
- topical treatments including steroids
- coal tar
- ultraviolet (UV) light therapy
- injected systemic treatment
- combination therapy
Scabies is easy to cure, but the symptoms of scabies are due to a hypersensitivity reaction (allergy) to mites and their feces. Even after you kill all of the mites and eggs, the itching may still continue for several weeks after treatment.
The treatment to kill scabies is messy. You apply a prescription lotion or cream to your entire body and leave it on for several hours, usually overnight.
More than one round of treatment may be necessary to eliminate an infestation. Your doctor may recommend every household member be treated, whether or not they show symptoms.
Remedies to help relieve the symptoms associated with scabies include using a cool compress, taking antihistamines, and applying calamine lotion. Learn more about treatment for scabies.
You should see your doctor if:
- you have any undiagnosed rash that doesn’t respond to self-care remedies
- you have psoriasis and unusually severe or widespread flare-ups
- your symptoms worsen or don’t respond to treatment
- you think you have scabies
- you’ve been exposed to someone with scabies
See your doctor as soon as possible if you have either scabies or psoriasis and you show signs of infection. These signs can include:
Knowing the differences between psoriasis and scabies will help you recognize the early symptoms and determine the best course of treatment. Speak with your doctor to learn more about your options.