Why is My Fitbit Giving Me a Rash?

Smartwatches have become increasingly popular for their health-tracking features. But they can also cause skin irritations and rashes for some people. These skin issues, known as contact dermatitis, are a common issue associated with wearing smartwatches. Learn more about contact dermatitis and how to alleviate irritated skin.

Contact dermatitis

The bottom line: Contact dermatitis occurs when something in the environment (either an allergen or an irritant) causes skin irritation or a rash. In the case of irritation from a smartwatch, the materials of the watch can cause an allergic reaction or sweat and friction can cause irritation.

Allergic contact dermatitis causes skin irritation and inflammation due to exposure to an allergen.

• Symptoms typically include redness, itching, swelling and blistering.
• Compared to irritant contact dermatitis, rashes caused by allergies tend to have less defined boundaries.
• Common allergens include certain metals, fragrances and preservatives found in skin products.
• Smartwatches can contain potential allergens such as nickel, latex, rubber or silicone. 
• The rash or skin irritation can begin hours or days after contact.

Irritant contact dermatitis causes irritation and inflammation due to direct physical or chemical irritation. 

• Unlike allergic contact dermatitis, irritant contact dermatitis does not produce an immune system response. It accounts for 80 percent of contact dermatitis cases.
• Symptoms include red, dry skin and a painful rash. Onset of symptoms typically occurs quickly.
• Frequent exposure to chemical agents (soaps, detergents or cleaning products) is a common cause.
• Friction or pressure in the form of tight-fitting clothing or objects can lead to irritation.
• Repeated exposure to moisture can weaken the skin's barrier and make it more prone to irritation.

Additional causes of skin irritation from smartwatches

Sweat accumulation can exacerbate skin irritation, especially when wearing the watch for extended periods.

• Sweat consists of 99% water along with electrolytes, lactate and urea.
• Typically, sweat evaporates off the skin, but it can accumulate underneath smartwatches.
• When present on the skin, especially in higher concentrations, urea can irritate the skin.

When friction causes repetitive rubbing or pressure on the skin, it can lead to irritation and inflammation. 

• The coupling of sweat and friction has the potential to exacerbate skin irritation by facilitating the infiltration of sweat through the skin's protective barrier.

Wearing a smartwatch too tightly can cause skin irritation due to several factors.

• Constant pressure and friction against the skin from a tightly worn band can irritate or chafe the skin.
• A watch that is too tight restricts airflow, preventing proper ventilation.
• The tightness can also trap moisture between the skin and watch band.

People with atopic dermatitis, the most common type of eczema, are more prone to developing contact dermatitis.

• Atopic dermatitis occurs when the skin’s barrier is compromised due to genetic factors – production of filaggrin, a protein important for skin barrier function, is reduced.
• This impaired barrier makes the skin more susceptible to external irritants and allergens.

How to get rid of a smartwatch rash

What to know: Treating a smartwatch rash involves a combination of self-care measures to alleviate discomfort and heal the skin. Here are various steps you can take to address the issue.

Remove the smartwatch so the skin can breathe and limit further irritation.

• Clean the area with soap and water to remove any sweat, dirt or irritants.
• Clean the smartwatch band at least once a week, as sweat, dirt, oils and bacteria can accumulate on the band’s surface.

Applying over-the-counter medications can reduce itching and redness.

• Hydrocortisone cream will help relieve inflammation by calming the immune system response to whatever caused the dermatitis.

Keep the area moisturized to lock in hydration.

• Applying a moisturizer to the affected area creates a protective barrier between the band and the skin.
• Keeping the skin hydrated will help promote healing.

Prevent future skin irritation by ensuring the band fits properly.

• A band that is either too tight or too loose can cause skin irritation due to friction or moisture accruing under the band.

Take breaks from wearing the watch to allow the skin to breathe and recover.

• For people who wear their smartwatch 24/7, including at night, remove the watch for at least 30 minutes or an hour per day.
• Dry both the smartwatch and your skin before putting it back on.

Choosing a smartwatch made with hypoallergenic materials can reduce the risk of skin irritation.

• Watches made with silicone or stainless steel are less likely to cause allergic reactions compared to nickel or latex.

Next steps: If the rash persists, worsens, or shows signs of infection, talk to your primary care provider or a dermatologist for further evaluation.