If you have a bad sunburn and want to keep it from blistering, your best window for action is the first few hours. Blisters form when UV damage is severe enough that fluid accumulates between the outer and deeper layers of skin, and this process can begin within hours of exposure. You can’t undo the damage, but cooling the skin quickly, reducing inflammation, and protecting the burned area can lower the chance that a red, painful burn progresses to one covered in fluid-filled blisters.
Cool the Skin Early and Often
The single most important step is getting heat out of your skin as fast as possible. A cool (not cold) shower, bath, or damp towel applied to the burned area helps slow the inflammatory cascade that leads to blistering. The Mayo Clinic recommends cooling the skin for about 10 minutes at a time, several times a day. The sooner you start after sun exposure, the better.
Don’t use ice or ice packs directly on sunburned skin. It sounds logical, but ice can damage tissue that’s already compromised and cause further injury. Cool tap water is the right temperature. If you’re using a damp towel, re-wet it as it warms up so it keeps drawing heat away from the skin.
Take an Anti-Inflammatory Pain Reliever
Ibuprofen or naproxen (common over-the-counter anti-inflammatories) can help reduce the swelling and redness that contribute to blister formation. These work by blocking the production of prostaglandins, chemicals your body releases in response to UV damage that drive inflammation and fluid buildup. Taking one as soon as you notice a serious burn, rather than waiting until the pain peaks, gives it the best chance of making a difference. Follow the dosage on the package and keep taking it on schedule for the first 24 to 48 hours while inflammation is most active.
Moisturize Without Trapping Heat
Sunburned skin loses moisture rapidly, and dehydrated skin is more likely to break down and blister. A lightweight, water-based moisturizer or pure aloe vera gel can help. Apply it gently after cooling the skin. If the product stings badly, try refrigerating it first or switching to something with fewer added ingredients.
What you put on the burn matters just as much as what you don’t. Avoid petroleum jelly, butter, coconut oil, or any thick, oil-based product. These create a seal over the skin that traps heat and blocks sweat from escaping, which can worsen the damage and increase the risk of infection. Also skip any product containing benzocaine or lidocaine. These topical numbing agents can trigger allergic reactions in some people and actually make the burn worse.
You may have heard that hydrocortisone cream helps. Despite being a go-to for many types of skin inflammation, topical steroid creams have not been shown to be particularly effective for sunburn, according to clinical evidence reviewed in the MSD Manual. They won’t hurt in most cases, but don’t count on them to prevent blistering.
Drink More Water Than Usual
A severe sunburn pulls fluid toward the skin’s surface, which is exactly what creates blisters. It also increases what’s called insensible fluid loss: water that evaporates through damaged skin without you noticing. This means you can become mildly dehydrated even if you don’t feel thirsty. Drink extra water and fluids with electrolytes in the 24 to 48 hours after a bad burn. Staying well-hydrated won’t stop blisters on its own, but dehydration makes your body less efficient at repairing tissue and managing inflammation.
Protect the Burn From Further Damage
Burned skin is extremely vulnerable. Any additional UV exposure, even brief, can push a borderline burn into blister territory. Stay out of the sun entirely until the redness has faded. If you have to go outside, cover the burned area with loose, soft clothing rather than relying on sunscreen, which can irritate raw skin.
Avoid tight clothing, rough fabrics, or anything that rubs against the burn. Friction on inflamed skin increases the chances of the top layer separating from the layer beneath it, which is the mechanical basis of blister formation. Loose cotton is your best option. At night, keep sheets light and consider sleeping in a cool room to prevent overheating the damaged area.
What Blistering Actually Means
A sunburn that blisters is a second-degree burn. Unlike a first-degree burn, which only affects the outermost layer of skin, a second-degree burn means the damage has reached the layer underneath. The fluid-filled pockets are your body’s attempt to cushion and protect that deeper tissue while it heals. This distinction matters because second-degree sunburns carry real risks: dehydration from fluid and electrolyte loss, skin infections if blisters break open, and long-term skin changes that persist after healing.
If blisters do form despite your best efforts, don’t pop them. The intact blister acts as a sterile bandage over the wound. Breaking it open exposes raw tissue to bacteria and dramatically increases infection risk. Let blisters drain on their own and keep the area clean.
Signs the Burn Needs Medical Attention
Sometimes a sunburn is severe enough that home care won’t cut it. If you develop blisters along with any of the following, the burn has triggered a systemic response that may need treatment: fever, chills or shivering, headache, nausea or vomiting, or skin that looks bright red and is oozing. Large blisters covering a wide area, blisters on your face, or blisters in a young child also warrant a call to a healthcare provider. Harvard Health notes that these symptoms can indicate sun poisoning, a more serious reaction where your body is struggling to manage the extent of the damage.