– Government regulators issued a consumer advisory Monday on the risks of bitcoin and other digital currencies, warning that the virtual funds expose users to volatile exchange rates, hacking, scams and theft.

Markups and transaction fees for digital funds such as bitcoin, XRP and Dogecoin can cost consumers more than using credit cards or regular cash, and the companies that issue digital currencies aren't backed or insured by any government, according to the six-page alert from the Consumer Financial Protection Bureau, a federal watchdog agency.

The advisory also cautions consumers that digital currencies can experience huge price fluctuations due to speculation and the lack of regulation. Bitcoin's price has fallen by as much as 80 percent in a single day.

Consumers who use or invest in virtual currencies "are stepping into the Wild West," the bureau's director, Richard Cordray, said in a statement.

"Virtual currencies may have potential benefits, but consumers need to be cautious and they need to be asking the right questions," Cordray said.

In addition to issuing the advisory, the bureau announced Monday that it will start collecting consumers' complaints about virtual currencies on its website, www.consumerfinance.gov.

An official with the trade group Bitcoin Foundation shrugged off the advisory as standard practice.