Blisters On The Feet: The basics

Here you can learn a little or a lot about foot blisters. We have you covered with the basics up top if you want to get into the real gritty details read on for a more detailed analysis.

Foot Blisters: What are they actually?

Blisters are a response to an irritation of the skin. They are fluid-filled vesicles that form when frictional forces repeatedly stretch the skin, creating small tears between the skin layers that then fill with fluid. The deeper the tissue damage, the more likely blood will also be present within the blister. 

Blisters on the feet can be resultant from a range of different causes but the two most common are friction and pressure. Often allergies, burns and bites can also lead to blistering of the skin. It is important to note that if no direct cause is apparent, underlying disease or infection may be present and therefore further investigation is warranted.

How do blisters present?

A fluid-filled lump within the skin present at the sight of trauma or irritation. Due to the pressure caused by this fluid between the layers of the skin, blisters are often painful and can impact heavily on activity.

What to do if you have a blister on your foot?

Relieving the pressure by lancing the blister is often beneficial and can give a level of pain relief to the patient. It is important that infection control protocols are adhered to due to the risk of infection. Lancing a blister still has some clinical considerations to take into effect around healing potential, infection, have you been able to remove the offending friction?

If the cause of the foot blister is clear, such as footwear or certain activity, an immediate referral to a podiatrist for specialist footwear advice or modification is advised as to avoid recurrence and assist in future management. 

If the causative factor of the blister is not so clear, further investigation into a potential underlying disease or infection is beneficial. 

While awaiting podiatry assessment therapeutic advice that is unlikely to cause harm and potentially be beneficial is:

  • Education: Pain education, reassurance, avoidance of nocebic language
  • A dressing plan, employing a sterile dressing and antibacterial ointment
  • Wear shoes you feel MORE comfortable in
  • Change your socks regularly and dry your feet well following showering or water-based activity
  • Refer to or see a podiatrist:
    “The podiatrist will assess you and give a clear diagnosis, work out why it is happening and plan to get you back to where you want to go. They will look at capacity, loading and plan accordingly. You might need to change your shoes, do appropriate exercises, use devices like orthotics to manage loading. They will advise you what is needed for your sore feet.”

What not to do

Nothing. Blistering of the skin is not only painful but poses a risk of infection. If an appropriate, ongoing treatment plan is not in place to avoid recurrence a patient may be at risk of serious complications.

An In-Depth Look at Foot Blisters

What’s actually happening when a blister forms on the foot?

Friction blisters result from shearing forces within the epidermis of the skin. This results in microtears and separation between the layers of skin; hydrostatic pressure then causes these areas to fill with fluid. Moist skin produces a higher frictional force than that of wet or dry skin, increasing the risk of blistering (Zone, 2019). 

In a similar fashion, blisters can also result from direct impact trauma, burns, hypersensitivities or overlying fracture sites. In some instances where no clear causative factor can be determined, blistering may be resultant of underlying disease or infection. A group of autoimmune blistering diseases cause a loss of cohesion between the cells of the skin, resulting in widespread blistering. If left untreated the impacts on morbidity and mortality can be significant (Welsh, 2009).

Presenting symptoms of foot blisters

Typically pain associated with a fluid-filled lump within the skin. In the case of friction blistering, these lesions occur at the sights of highest irritation. The surrounding tissue may be erythematous and painful to touch. 

Clients will often clearly describe the causative incident. This may range from a night on the town is poorly fitted shoes to the use of a new cream received as a gift. If however multiple blisters appear suddenly without clear causation or the lesion appears infected, further investigation into an underlying disease or condition is warranted.

Myths, falsehoods and quarter truths about blisters

“There is nothing to worry about; blisters are a part of life” 

Although the occasional blister caused by an occasional shoe may not present any immediate cause for concern, ongoing blistering can be debilitating and significantly impact activity. They also pose a portal of entry and therefore a serious risk of infection if not treated correctly. It is important that the underlying cause is discovered and managed appropriately.

“Just pop the blisters as they appear” 

Blisters form to protect the underlying tissue against damage. If the roof of a blister is removed, that tissue is left exposed to infection and irritation which is not only uncomfortable but may seriously impact on a person’s regular activity levels. All blisters should be treated in a sterile environment with the roof left intact where possible to minimise this risk.

Treatment options for foot blisters

The importance of medical management for underlying chronic disease cannot be overlooked. If, however, the causative factors are pressure and/or friction; many changes can be made to alter this force placement and therefore minimise the risk of future blister formation. 

Changes or modifications to current footwear, orthotic devices to optimise the load on skin or alterations to foot hygiene practices can all prevent and manage chronic blistering.

Further resources

 - Friction Blisters. Up to Date (2019). Zone, J.  

 - Blistering Conditions of the Skin. Australian Family Physician (2010). Welsh, B.