Rashes

Considerations:
Often, the cause of a rash can be determined from its visible characteristics and other symptoms.

Common Causes:

Note: There may be other causes of rashes. This list is not all inclusive, and the causes are not presented in order of likelihood. The causes of this symptom can include unlikely diseases and medications. Furthermore, the causes may vary based on age and gender of the affected person, as well as on the specific characteristics of the symptom such as location, quality, time course, aggravating factors, relieving factors, and associated complaints. Use the Symptom Analysis option to explore the possible explanations for rashes, occurring alone or in combination with other problems.

Home Care:
FOR CONTACT DERMATITIS ONLY
Rash prevention is preferred to treatment. Avoid contact with clothing, cosmetics, deodorants , etc. that cause a rash.

Washing thoroughly with soap and water may remove chemicals on the skin and is particularly important with materials like cement dust. Oily substances can be removed with rubbing alcohol, or by paint thinner followed with a soap and water rinse to prevent contact dermatitis from the cleaner itself.

For rashes caused by poison ivy - Domeboro powder or tablets (available without prescription), hot water, and hydrocortisone cream to achieve relief from itching are recommended.

If skin is dry, avoid drying soaps and apply a heavy cream to skin after bathing.

Calamine and hydrocortisone may reduce itching.

Call Your Healthcare Provider If:

  • home treatment is ineffective, or if symptoms persist or worsen.
  • other symptoms accompany the rashes.



What to Expect:
The medical history will be obtained and a physical examination performed. Questions will be asked about recent exposure to various substances and the rash will be examined. A dermatologist is most qualified to deal with skin disorders.

Medical history questions documenting your symptom in detail may include:

  • type of rash
    • Does it look like pinpoint red spots ( petechiae )?
    • Does it look like small red areas ( purpura )?
    • Does it look like bruises ( ecchymoses )?
    • Has it occurred more than once without known cause (recurrent)?
    • Does it look like hives ?
    • Does it look like blisters ?
      • Are they filled with yellow or honey-colored fluid?

    • Does it look like ulcerations?
    • Does it look like dry, tough skin growth (keratosis)?

    • Is the rash scaling or crusting?
    • Does it look like small, solid, red, elevated bumps ( papule )?
    • Does it look like both a macule (flat area) and papule (small bump)?
    • Is it a slightly elevated flat lesion (plaque)?
    • Does it have characteristics of acne rosacea ?

  • location
    • Does the rash cover the entire body or is it localized?
    • Where is it specifically?
    • Is it on the lower extremities?
      • Is it over the muscles that straighten the leg (extensor surfaces)?

    • Is it on the upper extremities?
      • Is it over the muscles used to straighten the arm (extensor surfaces)?

    • Is it on the genitals?

  • distribution
    • Is the rash spreading to other areas?
    • Does the amount of skin area affected increase over time (enlarging)?
    • Is the number of skin lesions increasing over time?
    • Is it at the site of a skin injury (cut, scrape, etc.)?
    • Is it at a site of chronically damaged skin (e.g., burn )?
    • Do lesions affect only one side of the body (unilateral) or both (bilateral)?
    • Is the rash beginning on hands or feet ( distal extremities)?
    • Have the sores gradually increased in size over months to years?
    • Are the lesions on exposed skin?
      • On sun exposed areas only?
      • Did the lesions begin at the site of an exposure?

  • quality or color
    • Is the skin darkening ( hyperpigmentation )?
    • Is the skin thickening?
    • Is the skin red (erythematous) or is it flesh colored?

  • shapes and borders
    • Do the lesions have sharp, distinct borders?
    • Do they have a bulls eye appearance (irisated)?

  • time pattern
    • Did the rash begin suddenly (within hours) or slowly and gradually?
    • How long did the rash last?
    • Are there short-lasting episodes of rashes (transient)?
    • Does the same type of rash occur repeatedly (recurrent)?
      • How often does the rash occur?

    • Did symptoms begin at birth or in infancy?
      • At what age?

    • Has the rash been long standing ( chronic )?
    • Did symptoms begin after a fever occurred and was relieved?
    • Which months does the rash usually occur during?
    • Did you have a vesicle that disappeared after a number of weeks? How many?

  • aggravating factors
    • Is it worse after taking a bath (or other exposure to water)?
    • Is it worse when you are stressed?
    • Does it occur after cold exposure ?
    • Is it worse after you use skin softening or smoothing agents (emollients)?
    • Is it worse after an exposure to the sun?

  • relieving factors
    • Does the rash get better after you use skin softening or smoothing agents?

  • changes over time
    • Did you have red cheeks followed within 2 days by a red spotty rash?
    • Was the rash of a brief duration and then went away (evanescent)?
    • Did the lesion change from a vesicle to an ulcer ?
    • Did the lesion change from an indurated nodule to a "beefy" red ulcer?

  • other
    • What other symptoms are also present?
    • Is there itching ?
    • Is there pain?
    • Is there drainage? What kind?

Diagnostic tests that may be performed include:

Intervention:
Steroid creams may be prescribed (see Corticosteroids - topical - medium to very high potency). Other interventions will depend on the type and cause of the rash.

After seeing your health care provider:
You may want to add a diagnosis related to a rash to your personal medical record.


This is a severe case of fungal infection on the face (tinea faceii). There are classical ring-shaped lesions on the face and ear (which is also infected) and the area is markedly swollen. (Courtesy of the Centers for Disease Control.)



This is a typical appearance of a poison ivy rash. The early lesion consists of multiple small blisters (vesicles), often in a line where the skin has brushed against the poison ivy plant. The person then spreads the toxins to other areas of the body by scratching. (Courtesy of the Centers for Disease Control.)



Eczema can be an acute or chronic inflammatory condition of the skin. It is characterized by redness, itching, and a host of cutaneous (skin) manifestations including papules, pustules, blisters (vesicles), weeping, cracking, crusting, or scabbing. (Courtesy of the Centers for Disease Control.)



This is a severe case of diaper dermatitis. Diaper dermatitis was more common before the advent of disposable diapers, which keep the skin very dry. Most diaper dermatitis is associated with infection from the yeast Candida. Other causes are ammonia burns from the bacterial action of urine, and environmental conditions from too infrequent diaper changes. This is a photograph of candidal dermatitis. The small red lesions on the tummy, just above the red diaper area, are referred to as "satellite lesions" (lower right side of the picture). (Courtesy of the Centers for Disease Control.)



Poison oak rash on the arm. Several plants produce toxins that cause skin reaction. This is the appearance of poison oak dermatitis. Note the typical linear streaks produced either by scratching or brushing against the plant. (Courtesy of the Centers for Disease Control.)



Newborn infants may have Erythema toxicum, a rash that is characterized by patchy redness with central papules (maculopapular). The rash is temporary, and the location may move (transient). (Courtesy of the Centers for Disease Control.)



A chancre on the penis caused by primary syphilis. The "chancre", a painless ulceration at the site of infection, is the classical presenting skin finding of syphilis. Chancres are highly visible in males but may go undetected in females.



Poison ivy rash on the arm: Poison ivy (Rhus toxicodendron) causes severe dermatitis in sensitive (allergic) individuals. Exposure is followed by the appearance of blisters (vesicles), often in lines or streaks where the individual has brushed the plant. Toxin on the skin can be spread to other areas by the fingers. It is not uncommon to find children with a swollen nose, eyes, and genitalia where they have spread the toxin to these areas while scratching, eating, rubbing their eyes, or using the bathroom.



Systemic Lupus Erythematosis: Lupus often produces a "butterfly rash" on the malar rash. This rash is usually red, smooth with no scale or crusts. Patients often have other symptoms like arthritis, fever, and muscle aches.



Psoriasis on the back: The severity ranges from mild symptoms to very severe skin disease and associated psoriatic arthritis. The typical skin lesion consists of red (erythematous) patches which run together (coalesce) into larger plaques. Thick silvery scales may develop on top of the plaques. Although this view is of the back, the front of the knee or outside of the elbow (extensor surfaces) are more commonly affected. The scalp, genitalia, and skin around the navel are other frequently-affected sites.







Fifth disease (erythema infectiosum, sometimes called "slapped cheek" disease) is an infectious illness caused by parvovirus B-19. There are few symptoms, but the rash is very characteristic. The infection causes bright red cheeks and a lacy (reticulated) rash on the arms and legs.



Erythema annulare on the buttocks and thigh: Erythema annulare is a descriptive term for redness appearing in ring shapes. This condition is generally asymptomatic with the exception of mild itching (pruritis). It may be associated with serious diseases, but in the majority of cases an underlying illness is never discovered.



Erythema annulare on the buttocks and thigh: Erythema annulare is a descriptive term for redness appearing in ring shapes. Shown here on the buttocks and upper thighs, this condition is generally asymptomatic with the exception of mild itching (pruritis). It may be associated with serious diseases, but in the majority of cases an underlying illness is never discovered.



Erythema annulare is a descriptive term for redness appearing in ring shapes. Shown here on the forearm, this condition generally produces no symptoms, with the exception of mild itching (pruritis). The condition may be associated with serious diseases, but in the majority of cases an underlying illness is never discovered.



Poison ivy is a type of contact dermatitis. Oils in the leaves and vines of the poison ivy plant produce blistering, redness, and intense itching. The first contact with poison ivy may produce little or no symptoms, but the individual becomes sensitized. The next contact may produce a marked rash. Toxin can be spread around on the skin by scratching. Subsequently, individuals often develop rash at remote sites such as around the eyes or genitalia.



The poison ivy rash, shown here on the forearm, may begin as an area of blister formation accompanied by stinging or itching. The blisters often appear in thin lines where the person has brushed against the plant. The blisters then break and the skin drains a clear yellow fluid ("weeps") for a period of time (determined by how sensitized the individual is). Crusting occurs as the fluid dries. Healing takes place generally within 2 to 3 weeks.



Poison oak (Rhus diversiloba or R. toxicodendron) produces a contact dermatitis similar to poison ivy, but milder. Notice the facial rash where the child has rubbed his eyes. Linear streaks on the chest are where the toxin has been spread across the skin by scratching.



This is a close-up view of poison oak dermatitis. Crusting has occurred over some of the damaged areas.



Psoriasis - lesions on the back The shapes of the lesions in psoriasis vary greatly, but typically they all exhibit redness (erythema), inflammation, elevation, and scaling. The scales are often silvery in color. The light color of the scales in the center of these lesions produces the ring-like appearance.



Psoriasis - lesions on the back: The shapes and sizes of the lesions in psoriasis vary greatly, but typically they all exhibit redness, inflammation (erythema) and scaling. The scales are often silvery in color. The scales are not prominent in this photograph.



Guttate psoriasis is a rare form of psoriasis. It appears rapidly and affects a large portion of the skin. This picture shows the appearance of guttate psoriasis on the arms.



Fifth (sometimes called "slapped cheek") disease is an infectious illness caused by parvovirus B-19. There are few symptoms associated with this disease, but the rash is very characteristic. The person usually has bright red cheeks and a lacy (reticulated) rash.



Fifth (sometimes called "slapped cheek") disease is an infectious illness caused by parvovirus B-19. There are few symptoms associated with this disease, but the rash is very characteristic. The person usually has bright red cheeks and a lacy (reticulated) rash.



Cellulitis is a deep infection of the skin, usually accompanied by generalized (systemic) symptoms such as fever and chills. The area of redness increases in size as the infection spreads. The center of the circled lesion has been biopsied.



When redness appears in ring shapes on the body, it is referred to as erythema annulare, shown here on the forearm. There are generally no symptoms, with the exception of mild itching (pruritus). It may be associated with serious diseases, but in the majority of cases, an underlying illness is never discovered.



This is a picture of guttate (shaped like a drop) psoriasis on the arms and chest. Guttate psoriasis is a rare form of psoriasis. It frequently follows a streptococcal infection, appears rapidly and affects the face, chest (trunk) and nearest (proximal) limbs. The patches are small and round or oval and have the typical appearance of psoriasis. It is seen almost exclusively in children. This photograph shows the diffuse and widespread coverage on the arm and chest.



This is a picture of guttate (shaped like a drop) psoriasis on face and neck. Guttate psoriasis is a rare form of psoriasis. It frequently follows a streptococcal infection, appears rapidly and affects the face, chest (trunk) and nearest (proximal) limbs. The patches are small and round or oval and have the typical appearance of psoriasis. It is seen almost exclusively in children. This photograph shows the diffuse and widespread coverage on the face and neck.



This is a picture of a systemic lupus erythematosis rash on the face. Lupus erythematosis often produces a "butterfly rash" or malar rash. Typically, the rash also appears on the nose.



This is a typical early appearance of a poison ivy rash, located on the knee. These early lesions consist of multiple small blisters (vesicles), often in a line where the skin has brushed against the poison ivy plant. The person may then spread the toxin to other areas of the body by scratching.



This is a typical early appearance of a poison ivy rash, located on the leg. These early lesions consist of multiple small blisters (vesicles), often in a line where the skin has brushed against the poison ivy plant. The person may then spread the toxin to other areas of the body by scratching.