Why does prickly heat occur?
Sweat glands cool the body by releasing sweat onto the surface of the skin. With heavy sweating, the stratum corneum becomes wet, and the ducts become clogged with scales, bacteria or thick cosmetics. Sweat is retained and released into the thickness of the skin, causing blisters or inflammation. In newborns, the ducts are not yet sufficiently developed, so they develop heat rash even with slight overheating. Adults are more likely to suffer in hot climates, during physical work, with fever and prolonged lying down.
- Hot and humid weather
- Wrapping up a child, wearing too warm clothes
- High body temperature
- Synthetic and tight clothing
- Prolonged bed rest
- Thick creams and oils that close pores
Types and symptoms
Miliaria crystalline is the most superficial: transparent blisters 1–2 mm in size without redness, which burst easily and look like dew drops. Miliaria rubra develops when the blockage is deeper and appears as small red nodules with itching or tingling. Miliaria profuseum is rare, usually affecting adults after repeated episodes in tropical climates, and appears as firm, pale nodules. When bacteria attach, pustules appear.
- Crystalline - transparent bubbles
- Red - itchy red nodules
- Deep - dense pale nodules
- Typical locations: neck, folds, armpits, chest, back, diaper area
- Tingling and itching, worse with sweating
How to distinguish it from other rashes
Miliaria appears where the skin sweats more or is covered by clothing, and noticeably decreases within a few hours after cooling. An allergic rash is most often associated with a new product or remedy and is not temperature-related. Infectious rashes are accompanied by fever, runny nose, deterioration of health and spread throughout the body. In newborns, erythema toxica and acne of the newborn look similar, which are also safe but require evaluation by a pediatrician.
- Allergic rash and urticaria
- Erythema toxicum of the newborn
- Newborn acne
- Folliculitis
- Chicken pox and other childhood infections
- Candidiasis of skin folds
When do you need a doctor and diagnostics?
The diagnosis is made upon examination; tests are usually not needed. You should consult a doctor if the rash does not improve after eliminating the overheating, pustules appear, the temperature rises, or the child becomes restless. The pediatrician will rule out infections and allergies and assess for signs of overheating and dehydration. For adults with frequent episodes of heat rash and severe sweating, your doctor may recommend testing to look for the cause of hyperhidrosis.
- Examination by a pediatrician or dermatologist
- Assessment of conditions: clothing, room temperature
- Exclusion of infectious diseases
- Sowing for pustular rashes
- Examination for severe sweating in adults
Treatment and prevention
The main treatment is to stop overheating. The child is undressed, the room is ventilated, bathed in cool but not cold water, and the skin is allowed to air dry. Clothes chosen are loose, made of cotton or linen. Fatty creams, oils and powders are not used: they clog the ducts even more. In case of severe itching, the doctor may prescribe a soothing lotion, and in case of infection, antiseptics. Usually the skin clears up in 2-5 days.
- Keep the baby's room at a cool temperature, around 20–22°C
- Dress your child according to the weather, do not wrap him up
- Cotton loose clothing and bedding
- Cool shower or bath after sweating
- Drinking enough in the heat
- Do not apply thick creams to affected skin