Heat Rash: Types, Causes, Symptoms, Diagnosis and Treatment

Heat rash is a fine pink rash caused by overheating that appears mainly on the chest, neck, groin, waistline, under the breasts, on skin folds and upper back. These rashes appear on the areas where the sweat ducts are blocked and inflamed due to heat and high humidity. They are also known as miliaria, prickly heat, heat rash or sweat rash. Heat rash is common in babies since their sweat ducts are not fully developed until at a later age.

Four Types of Heat Rash

1. Miliaria Crystalline
This type of heat rash appears as small, superficial and clear blisters that break easily due to mild friction. It is the mildest form of heat rash. It does not itch or cause discomfort in the patient.

2. Miliaria Rubra
Miliaria Rubra manifests as small, red bumpy or flat itchy spots. This type of heat rash occurs deeper within the dermis and prevents sweat from being released by the skin in the affected area. It results to this skin becoming sore and inflamed.

3. Miliaria Pustulosa
It is similar to Miliaria Rubra but in this case, the red bumps caused by heat are filled with pus. They also form lesions that become pustular and inflamed.

4. Miliaria Profunda
The least common type of heat rash, Miliaria Profunda, appears as deep red or white prickly lumps. When you sweat, the sweat is retained in the skin forming large flesh-colored bumps. This type of skin rash is not itchy, as the lesions appear below the itch receptors in the dermis. It affects adults who carry out physical activities for a long period and can become chronic.

Heat Rash Symptoms

a. Tiny water blisters especially in infants.
b. Small bumps or spots.
c. An itching or prickling sensation in the affected area.
d. Mild swelling.

Causes of Heat Rash

  1. Hot humid weather that overworks the sweat glands
  2. Excessive sweating under clothing that does not absorb sweat
  3. Ointments that block off sweat glands
  4. Undeveloped sweat glands in babies
  5. Hard exercise
  6. Radiation therapy
  7. Swaddling infants in heavy garments
  8. Lying in bed for a long period due to illness or immobility especially when you have a fever.

When to Seek Urgent Care near You for Heat Rashes

Heat rashes’ symptoms can be managed by using over the counter creams and mostly go away after a few days. However, urgent care services are required if you have the following symptoms:

  • Joint Pain
  • Headache
  • Increased swelling or tightness in the throat
  • Abnormal bruises or bleeding under the rash
  • Difficulty breathing
  • High fever or chills
  • Sudden drop in blood pressure
  • Peeling skin
  • Swollen lymph nodes in the armpit groin or neck.
  • Mouth ulcers
  • Streaks of red leading away from the rash
  • Pus filled blisters

Diagnosis of Heat Rash

Heat rashes are diagnosed according to the appearance of the lesions. A diagnostic test that involves rupturing a blister with a fine needle to assess the clear fluid is done. The doctor may perform a biopsy of the skin to confirm the diagnosis. It also helps rule out the possibility of it being a different condition with similar symptoms. A skin swab may also be carried out to rule out the possibility of a secondary infection.

Heat Rash Treatment

Mild cases of heat rashes disappear once the body has cooled down, but severe cases may need specialized treatment for rashes in San Antonio, TX. There are measures that can be taken to improve the symptoms. Some of them are listed below.

  1. Avoid sweating further by staying in a well-ventilated place.
  2. Wear loose light clothing that prevents overheating as this causes more itching.
  3. Avoid fabrics like wool that may irritate your skin more.
  4. Take a cool bath, shower, or use a cool compress for relief from itching.
  5. Pat or tap the itchy area instead of scratching it.
  6. Use lotions that will ease the itching and soothe the skin. Talk to your doctor before using any ointment or medication to make sure that they are suitable for you.
  7. If an infant has heat rash, do not dress them in tight heavy clothes or swaddle them with heavy garments. Do not lay them on plastic covered materials.
  8. You can use homeopathic substances like colloidal oatmeal or Aloe Vera to soothe the skin.

Urgent Care Services

We treat a wide range of urgent health conditions at our urgent care clinic in San Antonio, including:

Alongside our urgent care services, we provide complete care for: