Sunburn blisters are second-degree burns, meaning the UV radiation has penetrated through the top layer of your skin and into the layer beneath it. The single most important thing you can do is leave the blisters intact. They’re filled with fluid that acts as a natural protective barrier, shielding the damaged skin underneath while new tissue forms. Everything else, from pain relief to dressing the area, builds on that one rule.
Why You Should Never Pop Them
It’s tempting to drain a sunburn blister, especially a large, tight one. But that fluid is doing real work. It cushions the raw skin below and keeps out dirt, debris, and bacteria. The moment you puncture a blister, you create an opening for infection.
If a blister breaks on its own, don’t peel away the dead skin. That loose flap still serves as a shield over the wound. Leave it in place, gently clean the area with cool water, and cover it with a loose, non-stick bandage. People with diabetes, HIV, or conditions requiring immune-suppressing medications should have a healthcare provider drain any large or problematic blisters with sterile equipment rather than attempting it at home.
Immediate Steps After Blistering
Cool the skin as soon as you notice blisters forming. A cool (not ice-cold) bath or damp cloth applied for 10 to 15 minutes helps pull heat out of the tissue. Avoid ice directly on the skin, which can cause further damage to already-injured cells.
Take an over-the-counter pain reliever like ibuprofen or acetaminophen as soon as possible. Ibuprofen has the added benefit of reducing inflammation, which helps with both swelling and pain. Starting early matters because the inflammatory response ramps up in the hours after the burn.
Drink extra water. Sunburns draw fluid toward the skin’s surface, and blistering burns pull even more. You can become mildly dehydrated without realizing it, which makes headaches, fatigue, and dizziness worse.
How to Cover and Dress Blisters
Small blisters in areas that aren’t rubbing against clothing can often be left uncovered. For larger blisters, or ones on your shoulders, back, or anywhere fabric rubs, a bandage prevents accidental rupture.
Use a non-stick gauze pad or a hydrogel dressing. Hydrogel dressings are mostly water-based, provide a cooling effect on contact, and won’t stick to the wound bed, so changing them is far less painful. Foam dressings are another good option: they cushion the blister against pressure and absorb fluid if it leaks. Avoid standard adhesive bandages placed directly over the blister, as pulling them off can tear the skin.
Change the dressing once a day, or sooner if it gets wet or dirty. Each time, gently rinse the area with cool water before reapplying a fresh bandage.
What Not to Put on Blistered Skin
Petroleum jelly, butter, coconut oil, and other oil-based products should stay away from sunburn blisters. They seal in heat and block pores, trapping sweat underneath and raising the risk of infection. Home remedies like toothpaste fall in the same category.
Avoid topical pain-relief sprays or creams containing benzocaine or lidocaine. These numbing agents can trigger allergic reactions in some people and actually worsen the burn. A fragrance-free aloe vera gel (without added alcohol) is a safer choice for the surrounding skin, though it shouldn’t be applied directly inside a broken blister.
Recognizing Infection
Because blistered skin is an open invitation for bacteria, watch the area closely over the following days. Signs that a blister has become infected include:
- Yellow or greenish discharge oozing from the blister, as opposed to the clear fluid that’s normally inside
- Increasing pain or warmth around the blister, especially if it’s getting worse rather than gradually improving
- Red streaks radiating outward from the blister site
- Fever developing after the initial burn
Any of these warrants prompt medical attention. An infected burn can progress quickly, and early treatment with prescribed antibiotics makes a significant difference.
When Blistering Signals Something More Serious
Widespread blistering sometimes comes with systemic symptoms that go beyond a typical sunburn. This is often called sun poisoning, and it can include fever or chills, severe headache, nausea and vomiting, and feeling extremely cold or shivery despite having a burn. These symptoms mean your body is dealing with a significant inflammatory response and possible dehydration.
The size of the burn matters too. Federal burn treatment guidelines classify second-degree burns covering more than 20 percent of body surface area in adults (roughly the front of both legs, or the entire back) as requiring specialized care. For children under 10 and adults over 50, that threshold drops to 10 percent. If blisters cover a large portion of your body, or you’re experiencing any of the systemic symptoms above, seek medical care rather than managing it at home.
Healing Timeline and Aftercare
Most sunburn blisters take one to three weeks to fully heal, depending on severity. In the first few days, the blisters fill with fluid and the surrounding skin stays red and tender. Over the next week, the fluid gradually reabsorbs and the blistered skin begins to dry and flatten. Eventually the dead skin loosens on its own.
Once the dead skin has clearly separated (typically after several days), you can carefully trim it away with clean scissors wiped down with rubbing alcohol or an antiseptic wipe. Apply a thin layer of antibiotic ointment and cover with a fresh bandage. Check the area daily until the new skin beneath looks smooth and no longer weeps fluid.
The new skin that emerges will be noticeably thinner, pinker, and far more sensitive to UV light than the surrounding area. It can remain sun-sensitive for months. Cover it with clothing or a broad-spectrum sunscreen rated SPF 30 or higher whenever you’re outdoors. Re-burning this new skin is easier than you’d expect and can lead to permanent discoloration or scarring.