Burns and Scalds First Aid: Sunburn and Heat-Related Skin Injury

What Sunburn Is (and Why It Can Become Serious)

Sunburn is a radiation burn caused by ultraviolet (UV) exposure. It injures the outer layers of skin and triggers inflammation. Many sunburns are mild and can be managed at home, but severe sunburn can behave like a significant burn injury: it can cause extensive skin damage, fluid loss, and systemic symptoms (feeling unwell beyond the skin).

1) Recognizing Mild vs Severe Sunburn

Mild sunburn (usually home care)

• Pink to red skin that is tender or warm
• Mild swelling
• Itching or tightness
• No blisters, or only very small, localized blisters
• Person otherwise feels well

More severe sunburn (higher concern)

• Intense redness, significant pain, or swelling that limits movement (e.g., eyelids swollen, hands too swollen to close)
• Large areas involved (e.g., most of back/torso, both legs)
• Blistering that is widespread, large, or rapidly increasing
• Symptoms beyond the skin: headache, nausea, dizziness, fever/chills, weakness
• Sunburn in a child, especially infants and toddlers

Heat-related skin injury vs sunburn

Hot weather can cause both sunburn and heat illness. Sunburn is primarily skin damage from UV. Heat illness adds whole-body overheating. If the person is confused, faint, vomiting repeatedly, or has very hot skin with minimal sweating, treat it as urgent heat illness and seek emergency care.

2) Cooling Measures and Skin-Soothing Principles

Step-by-step: cooling the skin

1. Get out of the sun immediately (shade or indoors). Continued UV exposure worsens the burn even if it no longer feels hot.
2. Cool the skin with a cool shower or bath, or apply cool, wet compresses for 10–20 minutes at a time. Repeat as needed.
3. Avoid ice directly on skin. Very cold exposure can further injure already-damaged skin.
4. Pat dry gently rather than rubbing.

Soothing principles (what helps and what to avoid)

• Moisturize while skin is slightly damp to reduce dryness and tightness. Use a fragrance-free lotion or gel.
• Choose simple products: fragrance-free moisturizer, aloe vera gel (if tolerated), or a light emollient. Test on a small area if the skin is very sensitive.
• Avoid irritating ingredients on burned skin: alcohol-based gels, strong fragrances, exfoliants, retinoids, benzoyl peroxide, and acids (AHA/BHA).
• Avoid heavy occlusive ointments on very hot, inflamed skin if they trap heat and feel worse. If a thicker ointment feels soothing later (as peeling begins), use a thin layer.
• Loose, soft clothing reduces friction. Cotton is often more comfortable than synthetic fabrics.

Practical example

If someone returns from the beach with a bright red, painful back and shoulders: move indoors, take a cool shower, then apply a fragrance-free moisturizer. Use cool compresses during the evening if heat and pain return.

3) Fluid Replacement and Rest

Sunburn can increase fluid loss through inflamed skin and often occurs alongside heat exposure. Rehydration and rest support recovery and reduce dizziness and headache.

Step-by-step: rehydration and recovery

1. Rest in a cool environment (fan or air conditioning if available).
2. Drink fluids regularly: water is fine; oral rehydration solution is helpful if the person has been sweating heavily or feels lightheaded.
3. Eat light, salty foods if tolerated (e.g., soup, crackers) to help replace electrolytes.
4. Avoid alcohol because it worsens dehydration.

Signs hydration is improving

• Thirst decreases
• Urine becomes pale yellow and more frequent
• Dizziness improves when standing

4) Blister Care and When Blistering Changes Urgency

Blistering suggests a deeper injury than simple redness. Blisters are the body’s protective dressing; opening them increases pain and infection risk.

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Blister care basics

• Do not pop blisters. Protect them from friction.
• If a blister breaks on its own, rinse gently with clean water, let it drain, and leave the loose skin flap in place if it lies flat (it can protect the raw surface).
• Cover for comfort with a non-stick dressing if the area rubs against clothing or is likely to tear. Change if it becomes wet or dirty.
• Watch for infection: increasing redness spreading beyond the blister, worsening pain, pus, bad odor, or fever.

When blistering increases urgency

• Widespread blistering (large areas of the body) or large blisters (especially on face, hands, feet, genitals) warrants medical evaluation.
• Blisters plus systemic symptoms (fever, vomiting, weakness) increases concern for significant burn injury and dehydration.
• Blistering in children should be assessed promptly because they dehydrate more easily and burns can be more serious relative to body size.

5) Red Flags: When Sunburn Is a Medical Concern

Seek urgent medical care (same day or emergency depending on severity) if any of the following occur:

• Fever, chills, or feeling very unwell
• Widespread blistering or rapidly worsening blistering
• Confusion, fainting, severe headache, or difficulty staying awake
• Persistent vomiting or inability to keep fluids down
• Signs of dehydration: very dry mouth, minimal urination, dark urine, dizziness on standing, sunken eyes (especially in children)
• Severe swelling (e.g., face/eyelids swelling shut) or severe pain not improving with home measures
• Eye involvement: significant eye pain, light sensitivity, vision changes (possible sun-related eye injury)
• Sunburn in an infant (young babies should not be sunburned; this needs medical advice urgently)

6) When to Seek Professional Care (Especially for Children)

Adults: consider professional evaluation if

• Sunburn covers a large body area (e.g., most of the back/torso or both legs)
• There is blistering that is extensive, very painful, or located on high-impact areas (hands/feet/face/genitals)
• Symptoms last beyond 48 hours without improvement, or pain and redness are worsening
• There are medical risk factors: immune suppression, significant chronic illness, or history of severe reactions to sun exposure

Children: lower threshold to seek care

• Any blistering sunburn in a child merits contacting a clinician for guidance.
• Large area redness (for example, a child’s entire back and shoulders) should be assessed, especially if the child is lethargic or not drinking well.
• Infants: seek medical advice urgently for any sunburn, even if it looks mild.

What to report when you call or arrive for care

• Age and weight (for children)
• When the sun exposure occurred and when symptoms started
• Areas involved (face, hands, feet, genitals are important)
• Presence and extent of blistering
• Fluid intake and urination frequency
• Any fever, vomiting, dizziness, confusion, or fainting

Practical triage guide