Severe sunburn needs immediate cooling, aggressive hydration, and careful skin protection to heal properly. Most second-degree sunburns (the kind with blisters) heal within one to three weeks, but how you treat the burn in the first 24 to 48 hours makes a significant difference in pain levels and recovery time.
Cool the Skin Without Overdoing It
Get out of the sun and into a cool environment as soon as possible. Run cool (not cold) water over the burned areas, or apply cool, damp cloths for 10 to 15 minutes at a time. Ice and ice-cold water can damage already-injured skin, so aim for a temperature that feels soothing rather than shocking. A lukewarm bath works well for large areas like your back or legs.
After cooling, apply a gentle moisturizer or pure aloe vera gel while the skin is still slightly damp. This helps lock in moisture. Avoid anything containing alcohol, lidocaine, or benzocaine, which can irritate burned skin or cause allergic reactions. Petroleum-based products trap heat, so skip those too.
Take an Anti-Inflammatory Early
Ibuprofen is the go-to over-the-counter option for sunburn because it targets both pain and the inflammation driving it. Take it as soon as you notice the burn developing. Starting early matters because the inflammatory response ramps up over the first 12 to 24 hours, often peaking a full day after sun exposure. Ibuprofen won’t shorten how long the sunburn lasts, but it can meaningfully reduce swelling and discomfort during the worst of it. Naproxen and aspirin work through the same mechanism if ibuprofen isn’t an option for you.
Drink More Water Than You Think You Need
A severe sunburn pulls fluid toward the skin’s surface and disrupts your skin’s ability to retain moisture. This means you can become dehydrated without realizing it, especially if the burn covers a large portion of your body. Drink water steadily throughout the day for at least 48 hours after the burn. If you notice dark urine, dizziness, dry mouth, or fatigue, you’re already behind on fluids.
Sports drinks or oral rehydration solutions can help replace electrolytes if you were also sweating heavily during the sun exposure. Avoid alcohol, which worsens dehydration.
How to Handle Blisters
Blisters mean the burn has reached the second layer of skin. Leave them intact whenever possible. The fluid inside is your body’s natural bandage, protecting the raw skin underneath from bacteria. Popping or peeling blisters dramatically increases your risk of infection.
If a blister breaks on its own, gently clean the area with mild soap and water, apply a thin layer of antibiotic ointment, and cover it with a non-stick bandage. Change the dressing daily or whenever it gets wet or dirty. Loose, breathable clothing over burned areas reduces friction that can rupture blisters.
What Recovery Looks Like
A mild sunburn (red, tender, no blisters) typically resolves within a few days to a week. Second-degree sunburns with blistering take one to three weeks to heal. During recovery, the damaged skin will peel as new skin forms underneath. Resist the urge to pull or pick at peeling skin, as this can tear into layers that aren’t ready to be exposed.
New skin underneath will be more sensitive to UV light for weeks or even months. Keep healing areas covered or protected with sunscreen once the skin has closed. Some people notice temporary discoloration (lighter or darker patches) where the burn was worst. This usually fades over several months but can persist longer on deeper burns.
Signs That Need Medical Attention
Most sunburns, even painful ones, can be managed at home. But certain symptoms signal something more serious:
- Blisters covering more than 20% of your body (roughly a whole leg, your entire back, or both arms)
- Fever above 102°F (39°C)
- Chills or shivering despite warm surroundings
- Extreme pain that doesn’t respond to over-the-counter medication
- Signs of dehydration like dizziness, reduced urination, or extreme thirst
- Pus seeping from blisters, which indicates infection
- Confusion, rapid breathing, or nausea, which can signal heat illness
Any sunburn on a baby under one year old warrants immediate medical care regardless of severity.
Watching for Infection
Broken blisters and raw, peeling skin are vulnerable entry points for bacteria. Over the days following a severe burn, watch for increasing redness that spreads beyond the original burn margins, warmth or swelling that gets worse instead of better, pus or cloudy fluid draining from blisters, and red streaks extending away from the burned area. A fever developing several days after the initial burn (rather than in the first 24 hours) is another red flag for infection rather than the sunburn itself.
Keep burned skin clean but avoid scrubbing. Gentle washing with mild soap once a day is enough. If you’re covering blisters with bandages, change them daily and watch for any odor or color change in the drainage.
What Not to Do
Several common instincts can make a severe sunburn worse. Butter, coconut oil, and other thick oils trap heat in the skin. Harsh exfoliants or scrubs tear fragile tissue. Hot showers intensify pain and swelling. Tight clothing creates friction over blisters. And continued sun exposure, even brief, can deepen a burn that’s still developing. UV damage keeps progressing for hours after you come inside, which is why a sunburn often looks and feels worse the morning after.
If you normally use retinol, glycolic acid, or other active skincare products, stop applying them to burned areas until the skin has fully healed. These ingredients are designed to increase skin turnover, which is the last thing damaged skin needs.