7 On Your Side investigates Fitbit rash

SAN FRANCISCO (KGO) -- You may remember Fitbit of San Francisco had a problem with its hugely popular fitness tracker, The Force, when thousands of users broke out in severe rashes. The device was recalled and now Fitbit has released a new product that is supposed to be safer, but can you wear it without worry? 7 On Your Side has been investigating this question.

Can the cause of a rash be a trade secret? That is one of the questions brought up in our investigation. Another question: if the new Fitbit tracker is safer, why are we seeing the same rashes as before?

It's been eight months since the Fitbit Force was pulled from store shelves for causing some users to break out in blistering rashes. 7 On Your Side was first to investigate the mysterious cause of the irritating problem. Now the company has released what it says is a safer product -- the Fitbit Charge -- telling customers, "We have learned many lessons from this experience and are incorporating these lessons into future products to ensure that the entire Fitbit community can continue to enjoy our fitness trackers."

"I went ahead and ordered it about a week ago," Fitbit customer Kory Deavers said.

Deavers loved his Fitbit Force but was among the 10,000 users who suffered a serious rash. Now he's among the first to try the new Fitbit Charge.

"I thought, OK, they must have fixed things. I put it on and headed out for the day," Deavers said. Hours later he felt a familiar tingling sensation. "It felt like something was irritating my wrist on that same spot, but I thought maybe it's just in my head. It can't be happening again."

It was not in his head, it was on his wrist. He saw a red lump under the Fitbit charge and posted a photo of it on Twitter.

He is not alone. Since Deavers posted, we have found seven more complaints saying the new Fitbit tracker was causing the same problem as the old one.

One user says his skin broke out 10 hours after using the Fitbit charge. Another user asked on Twitter, "Is anyone else getting a rash like this from the new Fitbit Charge?"

"I think they need to pull it back off the market until they can solve the problems and prove with testing that it's safe for people to wear," Deavers said.

Fitbit says it designed the new product with stricter standards. Most important, an adhesive compound suspected of causing most rashes can no longer contact the skin. Then why are charge users still reporting rashes?

7 On Your Side wanted to talk with Fitbit CEO James Park. He would not agree to an on-camera interview, but through a spokesperson he said, "We have been in contact with the handful of Charge users who have reported redness or skin irritation after wearing the product. If any users are experiencing these symptoms, we encourage them to remove the device and if symptoms persist, to contact a dermatologist."

The company says the rashes from the Charge are different than the ones caused by the Force and could just be an irritation caused by sweat or soap.

7 On Your Side first reported about the mysterious outbreaks back in February. That's when Diane Barlow of Dublin said, "I saw a big red, angry, itchy spot on my wrist."

Force users wondering what caused it.

"I wasn't sure why I was getting this rash," Matthew Kovinsky of San Francisco told us.

The company never released its findings about the specific reason. So, 7 On Your Side filed a Freedom Of Information request seeking documents Fitbit submitted to the Federal Government about the cause of the rashes.

Months later, 7 On Your Side received a whopping 802 pages and they tell us almost nothing. Hundreds of pages are blacked out completely, the government telling me Fitbit has a right, by law, to keep 7 On Your Side from seeing information it considers a trade secret.

"It sounds like they're just burying you with the paperwork, so you can't find out what the real truth is," Deavers said.

Fitbit's CEO responds, "We want to maintain confidentiality over the research and investigation of the Force, and we cannot share the specifics of our investigation. We can assure you that we relied on the analysis and opinions of highly respected analytical laboratories and scientific consulting firms, as well as numerous experts in their respective fields."

Fitbit tells customers if they had a rash previously they should consult a doctor before wearing any device. Also the Consumer Product Safety Commission now says it mistakenly omitted some documents from the huge 802 page release. We will be receiving them shortly and will share the results if they shed more light on this investigation.