American credit card debt is up more than eight percent from a year ago. That's the highest amount ever recorded. In these tough economic times, it's important to keep a close eye on your credit cards. Consumer Reports says some companies are doubling or even tripling their interest rates- and it's not just happening to people with a bad credit rating.

John Carmichael says he always made his credit-card payments on time and had never had problems with his credit rating. But earlier this year, the interest on his Bank of America Visa card nearly tripled overnight. From around eight percent to nearly 25!

"To jump from a low rate to a high rate in one fell swoop, with no justification in something that I did wrong, I think is bad business," says John Carmichael.

Bank of America says Carmichael had too much debt, even though his card balance was almost one thousand dollars below his limit. Carmichael speculates that banks are changing credit-card terms to compensate for their mortgage-related losses. Consumer Reports Chris Fichera says that's possible.

"Banks earn a large part of their revenue from credit cards. So when the mortgage meltdown hit, they turned to credit cards to make up for slacking profits," says Fichera.

Credit-card notices alert you to changes in your account. Although plenty are junk mail. don't toss out a notice without reading it. Otherwise you could miss important changes to your credit-card account.

Banks often give you the choice to stop using your card and pay off the balance at the old rate, which is what John Carmichael worked out with Bank of America to avoid a rate increase. But not everyone does that.

"Some economists fear that overextended credit-card holders could be the next shoe to drop in the economic crisis. With home-equity loans harder to get, some people are turning to credit cards to cover their expenses."

Consumer Reports says with so many banks changing their terms, you need to navigate this new credit card jungle with care.

Consumer Reports says if you're not happy with your credit card terms, make a switch. You can compare cards online at sites such as cardratings.com. Look for a card with a low interest rate and no annual fee. And always be sure you read through the card's terms and conditions before signing up, so there are no surprises later on.