A rash may be localized in one part of the body, or affect all the skin. Rashes may cause the skin to change color, itch, become warm, bumpy, chapped, dry, cracked or blistered, swell, and may be painful.
The causes, and therefore treatments for rashes, vary widely. Diagnosis must take into account such things as the appearance of the rash, other symptoms, what the patient may have been exposed to, occupation, and occurrence in family members. The diagnosis may confirm any number of conditions.
The presence of a rash may aid diagnosis; associated signs and symptoms are diagnostic of certain diseases. For example, the rash in measles is an erythematous, morbilliform, maculopapular rash that begins a few days after the fever starts. It classically starts at the head, and spreads downwards.
Skin disease
Symptoms
Usual area of body
Acne vulgaris
Comedones, papules, pustules and nodules.
Face, chest and back.
Acne
rosacea
Flushed appearance or redness.
Cheeks, chin, forehead or nose.
Boil
Painful red bump or a cluster of painful red bumps
Anywhere
Cellulitis
Red, tender and swollen areas of skin
Around a cut, scrape or skin breach
Insect bite
Red and/or
itchy bumps on the skin
Anywhere and can be sprinkled randomly
Erythema migrans /
Lyme disease
Expands over days or weeks to 5–70 cm (median 16 cm), circular or oval, red or bluish, may have an elevated or darker center, may have a central or ring-like clearing, may feel warm, not painful or itchy
[4][5]
Armpit,
groin,
back of knee, on the
trunk, under clothing straps, or in children's hair, ear, or neck
[6][7]
Allergic reaction
Irregular, raised or flat red sores that appeared after taking medicine/drugs or eating certain foods
Anywhere
Hidradenitis Suppurativa
Deep sebum filled cystic condition of apocrine gland overstimulation, caused by many internal and external factors e.g., stress, toxic environmental overload and immune impairment.
See Hidradenitis.
Hives
Bumps formed suddenly
Anywhere but usually first noticed on face
Seborrheic dermatitis
Bumps and swelling
Near glands
Cradle cap
Dry, scaly skin
Scalp of recently born babies
Irritant contact dermatitis
Red, itchy, scaly, or oily rash
Eyebrows, nose, edge of the scalp, point of contact with jewellery, perfume, or clothing.
Allergic Contact Dermatitis caused by
poison ivy,
poison oak,
sumac, or
Balsam of Peru[3]
Red, itchy, scaly or oily rash; can also be weeping or leathery.
Anywhere that came in contact with the irritant either directly or via transfer (e.g. from contaminated clothing.)
Allergic purpura
Small red dots on the skin, or larger, bruise-like spots that appeared after taking medicine
Anywhere
Pityriasis Rosea
Started with a single scaly, red and slightly itchy spot, and within a few days, did large numbers of smaller patches of the rash, some red and/or others tan
Chest and abdomen
Dermatitis herpetiformis
Intensely itchy rash with red bumps and blisters
Elbows, knees, back or buttocks
Erythema nodosum
Large red bumps that seem to bruise and are tender to touch
Anywhere
Psoriasis
White, scaly rash over red, flaky, irritated skin
Elbows and knees
Erythema multiforme
Red, blotchy rash, with "target like" hives or sores.
Anywhere
Measles
Red rash that is raised with a fever or sore throat.
Usually starts first on the forehead and face and spreads downward.
Chickenpox
Multiple blisters with a fever, cough, aches, tiredness and sore throat.
Usually starts first on the face, chest and back and spreads downward.
Shingles
Red blisters that are very painful and may crust
Anywhere
Fifth Disease
Started as a fever and then developed a bright red rash
Cheeks
Warts
Soft bumps forming that do not itch and have no other symptoms
Anywhere
Ringworm
Bald spot on the scalp or a ring of itchy red skin
Anywhere
Syphilis
Rash that is red but not itchy
Palms of hands or soles of feet
Jock itch,
yeast infection or
diaper rash
Red itchy rash
Groin
Tinea versicolor
Light coloured patches
Anywhere
Impetigo
Crusted, tan-colored sores
Near nose or lip
Scabies
Bite-like sores that itch and spread intensely
Usually start on hands or feet and spread everywhere
Rocky Mountain spotted fever
A fine rash with a fever and headache
Usually start on arms and legs including the hands and feet
Lupus erythematosus
A butterfly rash with achy joints
Forehead and cheeks
Jaundice or sign of
hepatitis
Yellowish
Skin, whites of eyes and mouth
Bruise
Blue or black area after being hit
Anywhere
Actinic keratoses
Scaly, pink, gray or tan patches or bumps
Face, scalp or on the backs or the hands
Keloid or
hypertrophic scar
Scar that has grown larger than expected
Anywhere
Lipoma
Soft or rubbery growth
Anywhere
Milia
Many white spots
On the face of a baby
Molluscum contagiosum
Small, firm, round bumps with pits in the center that may sit on tiny stalks
Anywhere
Scarlet fever
Becomes confluent and forms bright red lines in the skin creases of the neck, armpits and groins (
Pastia's lines)
Face, chest and back, whole body, armpits, inside elbows, groins
Sebaceous cyst
Bump with a white dome under the skin
Scalp, nape of the neck or upper back
Skin tag
Soft, fleshy growth, lump or bump
Face, neck, armpits or groin
Xanthelasma
Yellow area under the skin
Under eyelids
Melanoma
Dark bump that may have started within a mole or blemish, or, a spot or mole that has changed in color, size, shape or is painful or itchy
Anywhere
Basal cell carcinoma
Fleshy, growing mass
Areas exposed to the sun
Squamous cell carcinoma
Unusual growth that is red, scaly or crusted
Face, lip or chin
Kaposi's sarcoma
Dark or black raised spots on the skin that keep growing or have appeared recently
Anywhere
Erythema annulare centrifugum (EAC)
Pink-red ring or bullseye marks
Anywhere
The causes of a rash are numerous, which may make the evaluation of a rash extremely difficult. An accurate evaluation by a provider may only be made in the context of a thorough history, i.e. medications the patient is taking, the patient's occupation, where the patient has been and complete physical examination.[citation needed]
Treatment differs according to which rash a patient has been diagnosed with. Common rashes can be easily remedied using steroid topical creams (such as hydrocortisone) or non-steroidal treatments. Many of the medications are available over the counter in the United States.[10]
The problem with steroid topical creams i.e. hydrocortisone; is their inability to penetrate the skin through absorption and therefore not be effective in clearing up the affected area, thus rendering the hydrocortisone almost completely ineffective in all except the most mild of cases.[11]