Possible Causes of a Rash on Your Wrist

Lichen planus

Lichen planus is a skin condition characterized by small, shiny, reddish bumps. Sometimes these are punctuated by white streaks. The affected area can be extremely itchy and blisters may form. Although the exact cause of the condition isn’t known, some experts believe it’s an autoimmune reaction. This means that your immune system mistakenly attacks healthy cells.

The inner wrist is a common site for lichen planus to erupt. It’s also often seen:

• on the lower part of the legs
• on the lower back
• on the fingernails
• on the scalp
• on the genitals
• in the mouth

Lichen planus affects approximately 1 in 100 people. It occurs more frequently in middle-aged women. There also may be a link between lichen planus and the hepatitis C virus.

Diagnosis and treatment

A doctor can diagnose lichen planus based on its appearance or by taking a skin biopsy. It’s normally treated with steroid creams and antihistamines. More severe cases may be treated with corticosteroid pills or psoralen ultraviolet A (PUVA) light therapy. Lichen planus usually clears up on its own within about two years.

Eczema

If you have a rash that doesn’t go away quickly, your doctor may suspect it’s eczema. Eczema, or contact dermatitis, is a common condition. According to Cleveland Clinic, as many as 15 million Americans have some type of eczema. It’s more frequently seen in infants and children, but people of any age can have the disease.

Eczema may first appear as dry, flaky, raised patches of skin. It’s often called “the itch that rashes” because scratching the patches of affected skin can cause them to become raw and inflamed. These patches may also form oozing blisters.

Although eczema can appear anywhere on the body, it’s often seen on the:

• hands
• feet
• scalp
• face

Older children and adults frequently have patches of eczema behind their knees or on the insides of their elbows.

The cause of eczema isn’t entirely understood. It tends to run in families, and is often associated with allergies and asthma.

Diagnosis and treatment

Most doctors can diagnose eczema by looking at the affected skin. If you have the condition, it’s important to keep your skin moisturized. Your doctor may prescribe a steroid cream or creams containing anthralin or coal tar. Topical immunomodulators, such as tacrolimus (Protopic) and pimecrolimus (Elidel) are newer medications that show promise as treatment options without steroids. Antihistamines can help relieve itching.

Scabies

Scabies is a condition caused by tiny mites. These mites burrow into the skin where they take up residence and lay their eggs. The rash they produce is an allergic reaction to the mites and their feces.

The main symptom of scabies is an extremely itchy rash that looks like small, fluid-filled pimples or blisters. Female mites sometimes tunnel just beneath the skin. This can leave behind thin paths of grayish lines.

The location of a rash caused by scabies varies by age. In infants and young children, this rash may be found on the:

• head
• neck
• shoulders
• hands
• soles of the feet

In older children and adults, this may be found on:

• the wrists
• between the fingers
• the abdomen
• the breasts
• the armpits
• the genitals

Scabies infestation is highly contagious. It spreads by prolonged skin-to-skin contact, including sexual contact. Although scabies usually doesn’t spread by casual contact at work or school, outbreaks in nursing care facilities and child care centers are common.

Diagnosis and treatment

Scabies is diagnosed by visual examination. Your doctor may also use a small needle to dislodge a mite or scrape the skin to look for mites, eggs, or fecal matter.

Scabicide creams that kill mites are used to treat scabies. Your doctor will tell you how to apply the cream and how long you should leave it on before bathing. Your family, other people you live with, and sexual partners should be treated as well.

Because a scabies infestation is extremely contagious and mites can spread to clothing and bedding, it’s important to follow the sanitation steps given by your doctor. These may include:

• washing all clothing, bedding, and towels in hot water
• vacuuming mattresses, rugs, carpets, and upholstered furnishings
• sealing items that can’t be washed, such as stuffed toys and pillows, in plastic bags for at least one week

Rocky Mountain spotted fever

Rocky Mountain spotted fever (RMSF) is a contagious disease caused by the bacteria Rickettsia rickettsii, which is transmitted through a tick bite. The symptoms may include:

• a rash that starts on the wrists and ankles and gradually spreads toward the trunk
• the rash that appears as red spots and may progress to petechiae, which are dark red or purple spots that indicate bleeding beneath the skin
• a high fever
• a headache
• chills
• muscle pain
• nausea
• vomiting

RMSF is a serious disease that can be life-threatening. It may cause permanent damage to blood vessels and other organs, blood clots, and inflammation of the brain (encephalitis).

Diagnosis and treatment

RMSF requires immediate medical treatment. Because it can take days to get the results of blood tests for the disease, most doctors make a diagnosis based on symptoms, the presence of a tick bite, or known exposure to ticks.

RMSF usually responds well to the antibiotic doxycycline when treatment begins within five days of symptoms appearing. If you’re pregnant, your doctor can prescribe an alternate antibiotic.

Prevention is your best protection against RMSF. Use insect repellants, and wear long-sleeve shirts, long pants, and socks if you’re going to be in the woods or a field.

The takeaway

If you’re experiencing inflammation, itchiness, or other symptoms that are cause for concern, you should schedule an appointment with your doctor. They can work with you to identify what’s affecting your skin. From there, you can seek appropriate treatment and return to your daily activities.