The best thing to put on a foot blister depends on whether the skin is still intact. For an unbroken blister, cover it with a bandage, moleskin, or hydrocolloid blister bandage to protect the skin roof, which acts as a natural barrier against bacteria. For a blister that has popped or been drained, apply petroleum jelly and cover it with a nonstick bandage to keep the area moist while new skin forms underneath.
Leave the Skin Roof Intact
The thin layer of skin over a blister is doing important work. It shields the raw tissue beneath from bacteria and dramatically lowers your risk of infection. Whenever possible, resist the urge to peel it off. Even if the blister looks ready to pop, that natural covering heals faster and more cleanly than exposed skin.
If the blister isn’t causing significant pain, the best approach is simply to protect it from further friction. Cover it with a standard adhesive bandage, a piece of moleskin, or a hydrocolloid blister bandage and let your body reabsorb the fluid on its own. Most blisters heal naturally within 3 to 7 days this way.
Choosing the Right Covering
You have three main options, and each works a little differently.
Adhesive bandages are fine for small blisters in low-friction areas. They’re cheap and available everywhere, but they tend to slide or peel off on sweaty feet, especially during activity.
Moleskin is thicker and sturdier. The classic technique is to cut a donut-shaped pad: cut a piece about an inch larger than the blister on all sides, fold it in half, and cut a half-circle the size of the blister from the folded edge. When you unfold it, you get a hole that sits right over the blister. This lifts pressure off the blister while the surrounding moleskin absorbs friction. Cover the whole thing with gauze. One caution: moleskin can stick to the blister roof itself and tear it when removed, so always position the hole directly over the blister rather than laying moleskin flat across it.
Hydrocolloid bandages (sold as blister-specific bandages by brands like Compeed and Band-Aid) are the most effective option for active use. The hydrocolloid material absorbs fluid from the blister and forms a gel that keeps the wound moist, which speeds healing and reduces scabbing. These bandages also stay put through sweat and water, making them a strong choice for runners, hikers, or anyone who can’t stay off their feet.
When and How to Drain a Blister
If a blister is large, painful, or in a spot where it’s going to rupture on its own from pressure (like the ball of your foot or your heel), draining it yourself is reasonable. The goal is to release the fluid while keeping the skin roof in place as a protective layer.
Here’s how to do it safely:
- Wash your hands and the blister thoroughly with soap and water.
- Swab the blister with an antiseptic.
- Sterilize a needle with rubbing alcohol or an antiseptic wipe.
- Pierce the blister in several spots near its edge, not in the center.
- Gently press the fluid out, but leave the overlying skin completely in place.
- Apply petroleum jelly over the drained blister and cover it with a nonstick bandage or gauze pad.
Check and re-dress the blister daily. If fluid collects again, you can drain it the same way.
Petroleum Jelly Over Antibiotic Ointment
You’ll see advice to apply antibiotic ointment (like Neosporin or bacitracin) to a drained or broken blister. Plain petroleum jelly works just as well. Research published in the Journal of Drugs in Dermatology found no significant difference in infection rates between wounds treated with bacitracin and those treated with plain petroleum jelly. Antibiotic ointments containing ingredients like neomycin and bacitracin can actually cause contact dermatitis, irritating the wound and slowing healing.
Petroleum jelly keeps the area moist, prevents the bandage from sticking to raw skin, and lets new tissue form without the risk of an allergic reaction. It’s the preferred option.
What Not to Put on a Blister
Skip hydrogen peroxide and rubbing alcohol on an open blister. While both kill germs, they also destroy the healthy tissue your body is trying to grow. Hydrogen peroxide damages new cells at the wound site, potentially creating a larger wound than you started with. Plain soap and water is all you need for cleaning.
Avoid popping a blister and then peeling off the skin. That loose flap may look useless, but it protects the tender layer beneath far better than any bandage alone. Don’t apply butter, toothpaste, or other home remedies. These can introduce bacteria and trap heat against the skin.
Blisters on the Bottom of Your Foot
Weight-bearing blisters are trickier because every step pushes directly on the wound. A donut-shaped moleskin pad is especially useful here. By building up the area around the blister while leaving the blister itself uncovered in the center hole, you redistribute your body weight to the surrounding healthy skin. Cover the whole setup with gauze or a hydrocolloid bandage.
If you need to keep walking or running, a hydrocolloid bandage over the blister (with or without a donut pad) provides the most reliable cushioning. Change it when it starts to peel at the edges or if you notice moisture building underneath.
Signs of Infection
Most blisters heal without complications, but an infected blister needs medical attention. Watch for these signs: the blister fills with green or yellow pus instead of clear fluid, the skin around it feels hot to the touch, or the surrounding area turns red (which can be harder to spot on darker skin tones). Increasing pain, swelling, or red streaks moving away from the blister are also warning signs that the infection may be spreading.
Special Concerns for Diabetes
Foot blisters carry higher stakes if you have diabetes. Nerve damage in the feet, a common complication, means you might not feel a blister forming or notice when one becomes infected. The American Diabetes Association notes that many amputations start with minor foot injuries that go undetected. If you have diabetes, check your feet daily for blisters, sores, and redness. Any blister that doesn’t improve within a few days, or shows any sign of infection, warrants a call to your doctor rather than continued home treatment.