The symptoms of heat rash can range from superficial blisters to deep, red lumps.
Adults usually develop heat rash in skin folds and in places where clothing causes friction.
In infants, the rash is mainly found on the neck, shoulders and chest. The rash can also be present in the armpits, elbow creases and groin.
The types of miliaria are classified according to how deep the blocked sweat ducts are. There is a variation for each type.
The mildest form of heat rash is known as miliaria crystallina affects sweat glands in the top layer of the skin. This for is marked by clear, fluid-filled blisters and bumps that break easily.
Miliaria rubra (prickly heat) is a type that occurs deeper in the skin. Signs and symptoms include red bumps and itching or prickling in the affected area.
Occasionally the fluid filled sacs or vesicles of miliaria rubra become inflammed and pus-filled (pustular). This form is called miliaria pustulosa.
There is also a less common form of heat rash called miliaria profunda, which affects the dermis of the skin.
Retained sweat leaks out of the sweat gland into the skin, causing firm, flesh-colored lesions that resemble goose bumps.
Heat rash is caused by blocked or clogged sweat ducts. Instead of evaporating, sweat gets trapped in the skin causing inflammation and rash.
It has not yet been clarified why the sweat gland become clogged, but some factors seem to play a role, these include: immature sweat ducts that can easily rupture, trapping perspiration beneath the skin.
Heat rash is capable of developing in the first week of life, especially when the infant is warmed in an incubator, dressed too warmly or even has a fever.
Hot, humid weather can cause heat rash. Intense exercise, hard work or any other activity that causes heavy sweating can lead to heat rash.
Overheating in general can be a cause of heat rash as well. Prolonged body rest can be a cause of heat rash, especially for individuals with fevers.
4 Making a Diagnosis
No test are necessary in the diagnosis of heat rash, diagnosis is by appearance.
Setting up a doctor's appointment for heat rash is no necessary. However, severe heat rash has to be treated with the assistance of a doctor, specifically a dermatologist to be sure it is not a different condition.
It is important to be prepared for the appointment in advance. Listing down the question about heat rash can help in this preparation.
Questions one might ask the doctor include the following
What could have caused this rash?
How can I treat it?
Do I need to limit physical activity until the rash clears?
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