Isaac Brekken / New York Times file photoIn the next few weeks, the Consumer Product Safety Commission will conclude an investigation into the Fitbit Flex, a popular activity-monitoring wristband, prompted by complaints that the device was causing blisters, rashes and other serious problems.

Fitbit, the maker of popular activity-monitoring wristbands, ran into trouble earlier this year after some consumers complained of severe skin irritations from the Fitbit Force.

Soon, it will learn what the government has to say about another Fitbit product, the Flex.

The Consumer Product Safety Commission, the government agency in charge of regulating everything from toys to toaster ovens, in the next few weeks will conclude an investigation into the Fitbit Flex prompted by complaints that the device was causing blisters, rashes and other problems.

“CPSC staff is taking these incident reports involving the Flex seriously,” a spokesman for the commission, Scott Wolfson, wrote in an email.

He added that the investigation did not necessarily mean that a recall was likely and that the agency would issue recommendations to help fix the problem. Wolfson said those could include warning users about the risk of nickel exposure and of wearing the device too tightly.

Fitbit recalled more than 1 million Force wristbands in February, blaming similar skin irritations on either nickel, one of the most common allergens in the United States, or the wristband’s adhesive. Unlike in Europe, the United States has no regulations governing how nickel can be used in consumer products, which some experts have warned has led to a rise in nickel sensitivity and allergic reactions.

Fitbit fast-tracked its recall of the Force, meaning that it had 20 days to withdraw the product from the market after alerting the safety agency that there was an issue. Fitbit also faces legal action from consumers who say they were injured by the Force. Both the Force and the Flex measured physical activity, but the Force offered more features.

“Fitbit remains confident about the performance and safety of its Flex activity tracker,” a spokeswoman for the company, Stephna May, wrote in an email. “The surgical grade stainless-steel clasp on the Flex contains trace amounts of nickel that are below stringent EU standards. As with any product made of stainless steel, a limited number of users with nickel sensitivity may still experience an allergic reaction.”

May also said that Fitbit advised users not to wear the Flex too tightly and to keep it dry, as with other wearable devices, and that the company planned to issue new sizing instructions “to ensure proper wear.”

The safety commission received a number of complaints about the Fitbit Flex on its online database, Saferproducts.gov.

“My Fitbit Flex bracelet in black caused a terrible rash on my wrist and has not gone away in weeks,” one consumer wrote. “I do not know how rash came or how to get rid of it.”