Reviewed by medical experts • For informational purposes only
From blocked sweat to recovery, usual healing time and when to seek care.
Heat rash follows a fairly predictable course. Knowing the stages helps you tell a normal rash from one that needs care.
Stage 1: Sweat is trapped
In hot, humid conditions, sweat ducts block. You may feel only a slight prickling or tingling before anything shows.
Stage 2: Rash appears (hours)
Tiny clear blisters or red bumps appear on covered skin or in folds. Itching and prickling may increase with sweating.
Stage 3: Peak (1 to 3 days)
The rash is most noticeable and itchy. If the skin stays hot and sweaty, it may worsen.
Stage 4: Settling with cooling
When the skin is kept cool and dry, the ducts reopen. Redness fades, blisters dry up and itching eases, usually within 2 to 5 days.
Stage 5: Peeling and recovery
Mild flaking may occur as the skin heals. Normal skin returns, usually without scarring.
When the course goes wrong
What to do at each stage
Early cooling prevents progression. If there is no improvement in 3 to 5 days, or signs of infection, see a doctor.
Key point
The earlier you cool and dry the skin, the faster it settles.
Before your appointment
Note when the rash began, where it is and what makes it better or worse, such as heat, clothes, creams or sweating. List any products, medicines, oils or herbal pastes you have used, and whether anyone at home has a similar rash. For a baby, note fever, feeding, and what the baby wears and sleeps in. Take photos of the rash over a few days.
Written By
Dr. Daksh
BDS
Reviewed By
Dr. Varun Gupta
MD Pharmacology, MBBS
Last updated on
27 Sep 2022 • 06:23 PM (IST)
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