Some side effects can come with activity monitoring with a Fitbit Force health tracker, but they're not sore muscles or an accelerated heart rate -- rather, they involve skin irritation around the wrist.
More than 10,000 people have reported skin irritation -- including redness, rashes, itchy and dry patches, and blistering -- from their Fitbit Force, according to the US Consumer Product Safety Commission. Because of these issues, the CPSC posted Fitbit's official recall notice on its site on Wednesday. Now, all Force owners can get a full refund for their device.
The $129 Force, which is an upgraded version of the popular Fitbit Flex, comes in the form of a slim rubber wristband and is wired to count users' steps and monitor their sleep. The backside of the device contains stainless steel components that use trace amounts of nickel, along with latex-free elastomer materials and adhesives. Fitbit believes the skin irritation could be coming from some users' allergies to these materials.
Here's a statement that Fitbit emailed to CNET on Wednesday:
The Fitbit Force voluntary recall was officially announced today by the U.S. Consumer Product Safety Commission (CPSC). Fitbit has stopped selling Force and is currently working with the CPSC to conduct a recall. A thorough analysis by independent labs and medical experts revealed that the reactions reported by a small percentage of Force users were likely the result of allergic contact dermatitis and no issues were found with the battery or electrical systems. Some users may be reacting to the stainless steel used in the device -- although it is surgical grade and meets the most stringent regulatory standards -- while others are likely experiencing an allergic reaction to the materials in the strap or the adhesives used to assemble the product. We're working on our next-generation tracker and will announce details soon.
According to the CPSC, 9,900 people reported skin irritation from the Force and 250 people reported blistering. While these numbers seem high, they're actually accounting for less than 1 percent of the devices out there -- which is pegged at 1 million in the US and 28,000 in Canada.
The company announced that it stopped selling the Force and issued a voluntary recall of the device last month but didn't release details on the amount of people affected. Also, it wasn't clear if the recall extended to all users -- as it now does.
Updated at 5:25 p.m. PT with statement from Fitbit.