# Blisters > A blister is a small pocket of fluid that forms in damaged skin, most often on the hands and feet. Foot blisters usually come from repeated friction. Most settle with protection and a clean covering, and it's best not to burst them. Some need checking. Guide in [Skin and nails](https://footanklelowerlimb.com.au/learn/topics/skin-and-nails), from Foot Ankle Lower Limb: https://footanklelowerlimb.com.au/learn/blisters Reviewed by Andrew Schox, BSc(Hons) PGradDipPod MPod (Podiatrist) on 27 October 2026. Next review by 27 October 2027. - **A blister is a pocket of fluid** that forms in damaged skin, most often on the hands and feet. - **Friction is the usual cause on the feet,** especially with lots of walking, running or hiking. - **Leave it alone where you can:** protect an intact blister rather than burst it. - **Some blisters need checking:** signs of infection, and any blister or break in the skin if you have diabetes. ## What is a blister, and how common is it? A blister is a small pocket of fluid that forms in the upper layers of damaged skin. It can appear anywhere on the body, but blisters are most common on the hands and feet [1]. Most hold clear fluid. Some hold blood (a blood blister), or pus if the blister becomes inflamed or infected [1]. The blisters you get on your feet are usually friction blisters. A friction blister is a tear inside the top layer of skin, and it fills with fluid within about 2 hours [2]. Foot blisters are very common in runners and hikers [2]. ## What causes blisters, and who gets them? Foot friction blisters come from repeated shear: layers of skin sliding against each other as the bones beneath move, with a high friction force, again and again [2]. If you've recently started a lot more walking, running or hiking, or changed your shoes or socks, that's worth thinking about. Blisters can also come from heat (such as sunburn or a scald), chemicals such as detergent, allergic reactions, and conditions such as chickenpox and impetigo (a bacterial skin infection) [1][3]. If you have diabetes, take extra care. Diabetes can reduce feeling and blood flow in the feet, so you may not feel rubbing, pressure or small injuries [4]. ## What does a blister feel like, and how is it diagnosed? A blister usually looks like a reddened, tender patch of skin with a raised lump of clear fluid, or sometimes blood [5]. A podiatrist or doctor will look at it and ask about your activity, shoes and socks, and any recent burns or new products. An infected blister can be hot and filled with green or yellow pus, with red skin around it. Redness can be harder to see on brown or black skin [6]. Blisters from a burn, scald, sunburn or allergic reaction, or with no obvious friction cause, should be reviewed by a doctor rather than treated as friction blisters [3][5]. Other conditions, such as bullous impetigo and scabies (a skin condition caused by tiny mites), can also cause blisters [3]. ## What helps first? Care is mostly about protection. Where possible, don't burst a blister or remove its roof, because that can cause infection and slow healing [5]. Keep it covered and away from the shoe or equipment that caused it. If a blister has already burst, let the fluid drain, then cover it with a clean plaster or dressing. Don't peel or pick at the skin [6]. > [!tip] Try this > Cover an unbroken blister with a clean plaster or dressing, and wear different shoes or socks until it settles, so the spot isn't rubbed again. If the roof has come off, a podiatrist or doctor may use a sterile, non-stick dressing [7]. Draining a blister is a job for a clinician using sterile instruments, and blisters have different causes, so there's no single right treatment for all of them [7]. ## What helps if that isn't enough? If a blister is large, painful, slow to heal or infected, a podiatrist or doctor can look at it and choose the care that suits the cause [7]. They may drain it with sterile instruments. If it's infected, they may use antimicrobial wound products for a short time [7]. If you have diabetes, well-fitting shoes that support your feet and avoid pressure points matter a great deal [4]. A podiatrist can check your footwear and help you find a better fit. ## How long does it take, and how do I stop it coming back? How long a blister takes to heal isn't clear. What helps is keeping the roof on, not bursting it, and protecting the spot from more friction while it settles [5]. If blisters keep coming back, look at your socks and shoes: fit, pressure points and how quickly you've increased your activity. In military recruits, a specially designed boot sock with a liner was linked with fewer blisters than standard socks [8]. This doesn't show the same result for everyone. If you have diabetes, check your feet every day. A blister that isn't healing can become more serious, so see your podiatrist about it [9][10]. ## When to see a podiatrist See your GP or a podiatrist the same day if: - a blister looks infected: it's hot, has green or yellow pus, or the redness, swelling or pain is increasing. Without treatment an infection could spread to the skin or blood [3]; - you have diabetes and find a blister or any break in the skin, or your foot is red, warm, swollen, discharging, or you feel unwell. Pain may be absent even when there's a wound, and feet can worsen within hours [4][10]. For urgent advice when it isn't an emergency, call healthdirect on 1800 022 222 (24 hours a day), or go to a Medicare Urgent Care Clinic. See your GP if a blister is from a burn, scald, severe sunburn or allergic reaction [5]. See your GP soon if a blister is very painful or keeps coming back, is on your eyelids, mouth or genitals, or if several blisters appear with no clear cause [3]. See a podiatrist or your GP if you have circulation problems and a blister [11], or if a blister isn't healing. ## Common questions ### What is the best dressing for a blister? For an unbroken blister, a clean plaster or dressing that keeps the roof protected is usually enough. If the blister has burst, let the fluid drain first, then cover it. If the roof has come off, a podiatrist or doctor may use a sterile, non-stick dressing. Try to avoid peeling or picking at the skin. ### Why do I get blisters in the same place each time? Repeated blisters in one spot usually mean that area is being sheared again and again, often by a shoe or sock that fits poorly or by a sudden jump in activity. Check your footwear for fit and pressure points. If it keeps happening, a podiatrist can look at your shoes, socks and how you walk. ## Further reading - [Blisters on Clindice](https://clindice.com/blisters) - [Blisters — treatment](https://www.healthdirect.gov.au/symptoms/blisters), healthdirect - [Skin condition - Leeds Community Healthcare](https://leedscommunityhealthcare.nhs.uk/our-services-a-z/podiatry/skin-condition/), NHS - [The Royal College of Podiatry](https://rcpod.org.uk/common-foot-problems/blisters), Royal College of Podiatry - [Blisters](https://medlineplus.gov/blisters.html), MedlinePlus - [Blisters](https://www.nhs.uk/conditions/blisters/), NHS ## Sources 1. Blisters · nidirect. https://www.nidirect.gov.uk/conditions/blisters 2. Friction Blisters of the Feet: A New Paradigm to Explain Causation · Rushton R, Richie D · Journal of Athletic Training · 2024. https://doi.org/10.4085/1062-6050-0309.22 3. Blisters · NHS · 2017. https://www.nhs.uk/conditions/blisters/ 4. Diabetes and High Risk Foot Service · NHS. https://www.nhft.nhs.uk/foot-service/crc32/ 5. Blisters · Better Health Channel · 2002. https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/blisters 6. Blisters · NHS. https://111.wales.nhs.uk/encyclopaedia/b/article/blisters 7. Local therapeutic procedure for blisters of the skin: a position paper of the Initiative Chronic Wounds (ICW) · Dissemond J, Bültemann A, Gerber V et al. · Dermatologie (Heidelberg, Germany) · 2022. https://doi.org/10.1007/s00105-022-05013-5 8. Influence of Boot-Sock Systems on Frequency and Severity of Foot Blisters · Knapik JJ, Hamlet MP, Thompson KJ et al. · Military Medicine · 1996. https://doi.org/10.1093/milmed/161.10.594 9. Download.cfm · NHS. https://www.hacw.nhs.uk/download.cfm?doc=docm93jijm4n12885.pdf&ver=23234 10. Diabetes - I’m worried about my foot – is it serious? · The Queen Elizabeth Hospital King's Lynn NHS Foundation Trust · 2025. https://www.qehkl.nhs.uk/services/diabetes/im-worried-about-my-foot/ 11. Blisters — treatment · Healthdirect Australia · 2024. https://www.healthdirect.gov.au/blisters --- This page is general information, not a diagnosis or a treatment plan for you. For advice about your own feet or legs, see a podiatrist or your doctor. In an emergency, call 000.